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Über dieses Buch

This book gathers the latest research, innovations, and applications in the field of civil engineering, as presented by leading national and international academics, researchers, engineers, and postgraduate students at the AWAM International Conference on Civil Engineering 2019 (AICCE’19), held in Penang, Malaysia on August 21-22, 2019. The book covers highly diverse topics in the main fields of civil engineering, including structural and earthquake engineering, environmental engineering, geotechnical engineering, highway and transportation engineering, water resources engineering, and geomatic and construction management. In line with the conference theme, “Transforming the Nation for a Sustainable Tomorrow”, which relates to the United Nations’ 17 Global Goals for Sustainable Development, it highlights important elements in the planning and development stages to establish design standards beneficial to the environment and its surroundings. The contributions introduce numerous exciting ideas that spur novel research directions and foster multidisciplinary collaborations between various specialists in the field of civil engineering.



Finite Element Analysis on Torsion Behaviour for Tapered Steel Section with Perforation

A study of finite element analysis (FEA) on torsion behaviour for tapered steel section with perforation is presented in this paper. The attention was paid mainly to firstly determine the effect of the perforation on the torsion behaviour of tapered steel section and to know an optimal section of tapered steel section with perforation under torsion loading based on the results obtained from FEA of LUSAS software. Five (5) variables such as opening shape, web thickness and flange thickness were identified and analysed to know the effect on torsional rotation of tapered steel section. A total of one hundred and twenty (120) of finite element (FE) models were than employed in this analysis including tapered steel section without perforation. The results were expressed in terms of displacement and torsional resistance (TR). Based on the analysis result, it was clearly showed that there was no improvement on the engineering properties and performance of tapered steel section with perforation in term of TR. The presence of web opening will result in reduction of TR. It is concluded that all of the variables will affect the TR. In addition, weight was reduced as the material volume was reduce with the present of perforation.

Fatimah De’nan, Nor Salwani Hashim, Nor Amirah Yaani

Theoretical, CFD Simulation and Experimental Study to Predict the Flowrate Across a Square Edge Broad Crested Weir Depending on the End Depth as a Control Section

A rectangular broad crested weir is the one mostly used in hydraulic structures for measuring flow rates in open channels and rivers. This study is focused on finding the suitable position of the depth above the weir as control section for estimating the flow rate while avoiding the troubles of approach velocity. It was predicted that the end edge of the weir, as a control section, relates to the critical depth (Yc) as a function of the end depth (Ye). To determine the relationship between these, experimental tests were achieved with ten different values of the longitudinal slope. Statistical regression analysis indicated the relationship between Yc and Ye as about 1.522. Consequently, a new flow rate formula was derived to estimate the flow over the weir and provided a good agreement with the experimental tests. A 3D ANSYS FLUENT Ver. V.16.1 CFD model was also applied to simulate the problem and verify the equation. The water volume fraction and the stream flow pattern were taken into the consideration. The model was able to simulate the problem with a good accuracy for all cases with a percentage error less than 10% when compared to experimental results. Thus indicating that CFD models could be relied upon for describing complex flows.

Sadiq S. Muhsun, Sanaa A. Talab Al-Osmy, Shaymaa Abdul Muttaled Al-Hashimi, Zainab T. Al-Sharify

Optimization of Egg Shell Powder and Lime for Waste Soil Improvement at Open Dumping Area Using Monte Carlo Simulations

The waste soil at open dumping area is prone to settlement problems. There are many soil stabilization methods available that can be used to improve soil strength. The addition of egg shell powder and lime for waste soil improvement is studied in this research. Soil stabilization method using the waste material as replacement to improve the strength has been explored widely. In this research, the egg shell powder and lime is added to the waste soil with the mixing portion of 2.5% lime and 2.5% egg shell powder, 5% lime and 5% egg shell powder and 7.5% lime and 7.5% egg shell powder. The compressive strength is conducted on the waste soil samples with different mixing ratio. The optimum value of the compressive strength is simulated using Monte Carlo simulation. In conclusion, there is potential for the waste soil to be improved in terms of strength using lime and egg shell powder. The compressive strength of waste soil is added with 2.5% lime and 2.5% ESP, 5% lime and 5% ESP, 7.5% lime and 7.5% ESP gave the results of 36.39, 70.66 and 337.13 kN/mm2 respectively at curing of 28 days, which satisfies the soil improvement requirement. The Monte Carlo Simulation and optimization of the result using the mean value show that the compressive strength is increase when the data is simulated N = 16 to N = 20. It has proved that the accuracy of the result has increased by using Monte Carlo Simulation and optimization.

Nur Irfah M. Pauzi, Mior A. Aimran, Mohammad S. Ismail, Mohd Shahril M. Radhi

Preference Assessment and Prioritization of the Urban Green Space Features Using Qualitative Evaluation and AHP Decision Model

The global rapid urbanization process has forced the issue of urban green space to be importantly addressed with regards to promoting leisure opportunities, health benefits and aesthetic enjoyment of urban residents. Urban green spaces such as the public parks are very influential in contributing to the quality of life to communities in various ways. Their features represent the physical activity patterns, perceptions and the preferences of park users. At present, there is no attempt to explore the importance of these features in designing sustainable urban community parks. This paper uses the qualitative assessment to analyze the preferences of park users and expert decision makers to prioritize the urban green space features. The preferential statistics and the AHP-decision model were applied in the urban green space study of two prominent recreational parks in Ipoh, Malaysia. The results have indicated that the people’s aspiration towards an ideal public park has led to the associated changes and demands upon available green features. The outcome of the prioritize study shows that safety feature attributes are ranked as a most important attribute, followed in sequence by other attributes viz. maintenance, accessibility, property value, signage and lighting, visual pattern, facilities, location and water bodies. The prioritized feature attributes are considered significant in selecting the factors of urban green space in relation to urban residential living areas. It can positively assist in defining the components of future urban green space features in the global urbanization policy.

Mohd Sanusi S. Ahamad, Rabi’ah Ahmad, Abdul Nasir Matori

Sustainability Assessment of the School Building Site (Case Study: Schools Built After 2003 in Karbala)

Sustainable schools are schools that aim to raise environmental awareness among students and teachers through positive environmental practices. The aim of these school is to reduce the negative environmental impacts, especially in the areas of buildings, water, energy, air and waste. The problem of the research lies in absence of application of sustainability concepts in the Karbala city school buildings, which negatively affects the performance of schools environmentally, economically and socially as well as on the grade of scientific students and their awareness of the sustainability dimensions and its role in the establishment of environmentally friendly communities. The research focuses on schools in Karbala where the education in Karbala schools has been determined. The researcher then studies the concept of the sustainable school, its principles and applications on the school site to be used in line with the reality of Karbala city. An analysis of building sites for multiple schools in the city was conducted and an assessment of their sustainability using the SBAM method was undertaken to identify elements that represent weaknesses in order to describe and provide solutions to sustainability problems. At the end of the study, the researcher found that Karbala school sites are at a level of non-sustainability but not far from achieving them.

Ghayath Ali

Development of Design Acceleration Response Spectrum for Building Based on New Indonesian Seismic Hazard Maps 2017

Research and development of Indonesian Seismic Hazard Maps in 2017 (IHSM-2017) have a direct impact on the development of seismic resistance code for building design in Indonesia. The development of new Indonesian seismic code for building and non-building design is still on-going, following the development of ASCE/SEI 7-16. This paper describes the development of design acceleration response spectrum (DARS) for building design. DARS-2019 is developed following the same method describes in the Indonesian seismic code [9] and ASCE/SEI 7-16. The study for developing DARS-2019 was performed at 35 cities in Central Java and Yogyakarta Provinces, Indonesia. A comparative study with 2012 seismic code (DARS-2012) was also performed in this study to evaluate the improvement of the DARS at those 35 cities. The analysis was performed for three different site soil classes (hard soil/SC, medium soil/SD and soft soil/SE). The purpose of this study is to evaluate the direct impact of the new ISHM-2017 on DARS-2019. Based on the analysis conducted at 35 cities, the improvement of DARS-2019 compared to DARS-2012 for site classes SC, SD and SE are less than 0.1 g except for site class SC at five cities located close to Opak fault trace.

Windu Partono, Masyhur Irsyam, I. Wayan Sengara, Asrurifak, Frida Kistiani, Undayani Cita Sari

Trip Distribution Gravity Model of Al-Diwaniyah City: A Case Study

The main objective of this study is the construction of trip distribution models for allotting trips from each traffic analysis zone to each other in the study area. For this purpose, the city of Al-Diwaniyah in Iraq has been separated into five subdivisions with 70 traffic analysis zones covering a total area of 52 km2. Surveys were conducted throughout prearrangements with high schools, administrations, and some colleges. Five hundred questionnaires were distributed in the city with a response rate of 78.4%. Standard TransCAD Gravity Model software version 4.5 was used in the trip distribution modeling process. The gamma function was adopted for developing the friction factors for Al-Diwaniyah. The gamma coefficients were obtained for five trips purposes in Al-Diwaniyah. The friction factors were determined for up to 60 min using one-minute intervals. With increased travel time, friction factors decrease when the gamma coefficients (b and c) have negative values. The average trip length for the gravity model is range between 12.5 and 18.5 min for the five trip’s purpose that was considered in the study. The trip Length frequency distribution (TLFD) of a home base work trip is 20–25 min. Home base educational trips have two ranges: 11–15 min for short trips (schools within the same zone) and 16–20 min for long trips. The home base shopping trips have an average TLFD of 6–10 min because the shopping destinations are within the TAZs.

Rana A. Yousif, Sady A. Tayh, Abbas F. Jasim

Methods of Estimating Time of Concentration: A Case Study of Urban Catchment of Sungai Kerayong, Kuala Lumpur

Characterization of hydrologic processes of a catchment in relation to water resources structures design requires estimation of time-response characteristics which is used in hydrologic models. The time of concentration (Tc) is an essential component in hydrological modelling which is used in predicting the response time of a catchment to a storm event. There are many approaches in the estimation of time of concentration from literature. At gauged watersheds, Tc can be estimated using rainfall and a runoff hydrograph, while for ungauged catchments, empirical equations are used. In this study, variability of empirical methodologies and hydrograph separation method for evaluating Tc using data from past study on Sungai Kerayong, Kuala Lumpur is presented. Results of the study showed Gundlach, Carter and NAASRA methods are suitable for estimating Tc in the study area while Bransby-Williams and Ventura methods were the poorest in estimation of Tc in the study.

Rofiat Bunmi Mudashiru, Ismail Abustan, Fauzi Baharudin

The Permeability and Strength of Compacted Laterite Soil-Bentonite Mixtures for Landfill Cover Application

The most suitable soil type for landfill cover is the fine-grained soil with high clay content; however, clayey soils are also relatively low in shear strength. The laterite soils, which is regular with the Malaysian construction industry has been the main choice for landfill cover purposes in the country; however, upon investigation, the soils would normally have a permeability coefficient ($$k$$) in the order of 10−8 m/s or higher, thus are considered unsuitable for landfill application unless treated to meet the standard. The current study presents properties associated with permeability and shear strength of three laterite soils—LS1, LS2, and LS3—when treated by mixing with bentonite at 1, 3, and 5%. In each case, $$k$$ was found reduced with increasing bentonite content. However, for LS1, a 5% bentonite treatment was required to decrease $$k$$ by one order of magnitude, i.e. from 4.7 × 10−8 m/s to 9.3 × 10−9 m/s. For LS2, a 3% bentonite content was required to bring down $$k$$ from 4.26 × 10−8 m/s to 6.94 × 10−9 m/s, while for LS3, only 1% bentonite was sufficient to reduce $$k$$ from 3.25 × 10−8 m/s to 8.15 × 10−9 m/s. With the addition of the bentonite, the unconfined compressive strength (UCS) were found weakened to lesser than 200 kPa for all samples. Without bentonite, the UCS values for LS1, LS2, and LS3 were respectively 213 kPa, 207.84 kPa, and 156.19 kPa.

Ros N. Rosli, Mohamad R. Selamat, Harris Ramli

Investigation of Brick Masonry Behaviour Under Uniaxial Compression Test at Different Scales

In the early era of performing physical studies on scaled masonry model, masonry was taken to be isotropic material, like concrete and its strength and stiffness remained unchanged under scaling. On the contrary, there were also studies suggesting that masonry was an anisotropic material and scaling affected its strength. This paper covers the experimental findings of scale effect on solid clay brick unit and masonry prism subjected to uniaxial compressive loading. The effect of scaling on constituent materials was assessed prior to the investigation of scale effect on masonry prism. Based on experimental results, compressive strength of half scale brick units is higher than full scale brick units. Similarly, compressive strength of half scale masonry prisms is also higher than full scale masonry prisms. Elastic modulus of half scale masonry prisms is smaller than full scale masonry prism. The ratio of mortar to brick unit strength of full scale masonry prisms is found to be governing the extent of increase in compressive strength of half scale masonry prisms. The reduction of scale effect on compressive strength of downscaled masonry is possible with smaller ratio of mortar to brick unit strength.

Tze Che Van, Tze Liang Lau, Fadzli Mohamed Nazri

Spatial Risk Mapping of House Fly Habitat in South Seberang Perai Penang, Malaysia

This paper presents a case study on the problem of house flies’ hazard that frequently occurs in the surrounding area of South Seberang Perai (SPS). Among the important factors that were considered are the house fly breeding places, their fly distance, and their distribution patterns. It is widely known that the SPS district is famous for its animal husbandries sectors, such as pigs, poultry and cattle. The existence of these animal farms has caused the huge presence of house flies in this area. The study was specifically carried out to determine the relationship between house fly flying distances from their breeding places and the outspread to which the community settlements will be affected from this discomfort. The surveillance survey was initiated by collecting the coordinate locations of poultry farms and open garbage dumping sites using the Android GPS application. The GIS software was used in performing the various spatial analysis such as spatial classification and distance analysis. The mathematical overlay process was accomplished to determine the risk level based on the travel distances of house flies. The end results show the maps of the affected area in SPS in three different classes of risk categories i.e. very affected, moderately affected and less affected. This habitat risk map that can assist in future housing planning for favorable and healthy living.

Mohd Sanusi S. Ahamad, Nor Roshida Rosli

Capacity Estimation of Multi-lane Rural Highway: A Comparative Study

The highway capacity manual (HCM) of the United States of America provides techniques for evaluating the capacity and the quality of service of any facility. The present study is an attempt to determine the adequacy of the techniques in US HCM to predict the traffic performance of highways in Al-Anbar, Iraq. Capacity of the multi-lane rural highway that connects two cities in Al-Anbar Governorate, Iraq was estimated. Twenty sections of the multi-lane rural highway were selected and observed for this purpose. Data were collected using the video recording technique. Data were abstracted, processed and then analyzed using computer programs developed for this purpose. Three methods for estimating capacity were applied, which are, the enveloping curve technique, the best-fit technique, and the US HCM methodology. Results showed that the capacity estimation methodology using US HCM has limited application for the heterogeneous traffic situation prevailing in the studied sites. This finding is consistent with that obtained by previous studies in developing countries, such as India, Thailand, and Indonesia. The capacity estimate showed that the US HCM methodology tends to underestimate capacity unlike other techniques because the adjustment factor for the traffic composition is not applicable for all vehicle types in the traffic stream that has different equivalency units. Further, the underestimation is attributed partly by differences in driver behavior, vehicle characteristics, and roadside activities.

Mahdi Ibrahim Alkubaisi

CPTU Penetrations into the Marine Clays and Laterite Soils of Northwest Peninsular Malaysia

Site investigation penetrations by CPTU were carried out in Northwest Peninsular Malaysia to demonstrate the contrasting profiles between the marine clays of the coastal plains and the laterite soils of the inlands. From the findings, the trends of persistent low resistance with depth for the marine clays and fluctuating higher resistance with depth for the laterite soils were found quite consistent when evaluated in terms of either the cone resistance, sleeve friction, or standard penetration number. The CPTU interpreted behaviors for the various marine clays were clayey silt to silty clay, clay, sensitive fine grain, and silty clay to clay, to mention the most dominant ones, while for the underlying hard layer were sand and sand to silty sand. The CPTU interpreted behaviors for the laterite soils, among others, were silty clay to clay, clay, clayey silt to silty clay, silty sand to sandy silt, and sand to silty sand. In addition, the laboratory classification procedure, namely the Unified Soil Classification System, gave a different name for each of the CPTU interpreted behaviors, for the marine clays and for the laterite soils, which this paper shows and clarifies. The CPTU penetrations reaffirmed that the marine clays of the quaternary coastal plains are clayey and very soft while the laterite residual soils of the inlands are relatively more sandy and stronger.

Mohamad R. Selamat, Dziaudin Z. Abidin, Muhammad Z. Yusoff, Ros N. Rosli, Muhd H. Ramli, Ashraf Q. Alkinani, Reda A. Abdelhalim

Finite Element Analysis of the Screw Arrangement Effects on the Connection Behaviour for Cold Formed Steel Truss Systems

Due to advantages of lightweight section with high strength to weight ratio, easy for transportation, can be manufactured in different configurations and shapes, the demand for cold formed steel (CFS) has rapidly increased. There were several types of connections such as bolt, welded, rivet and screw. Recently, limited researches were noticed especially when it was used on steel trusses. Rectangular hollow section (RHS) and lipped channel (LCS) were selected as material of cold formed steel (CFS) truss where consist of interconnected small elements such as web, top and bottom chord and other components. In this research, the screw connections of Fink and Howe truss at the side and peak location were being modelled using LUSAS. The behaviors in different cases through modification of screws arrangement were being compared. The identification of connection strength based on the results such as displacement, shear, stress and moment were discussed through finite element analysis. Thereafter, according to procedures prescribed in Eurocode 3 design checking on the shear and tension resistance of screw connection were carried out as a validation of design procedure for connection of cold formed steel (CFS). From the outcomes results, it was observed that both types of cross sections gave different performances. In general, when the arrangement of screws was emphasized the function of screw connection necessarily improved but was not crucially affected. However, such arrangement of screws was appropriate to use in truss system design.

Fatimah De’nan, Kok Keong Choong, Jessica Si Jia Loo, Nor Salwani Hashim

Seismic Hazard Analysis Study of New Semarang International Airport Due to Shallow Crustal Fault Earthquake Scenario

Ahmad Yani International Airport is located in Semarang (the Capital City of Central Java Province) Indonesia. The airport was first operated on June 6 2018 and designed it using 2012 Indonesian Seismic Code (SNI 1726:2012 in Seismic resistance design codes for building and other structures, Jakarta, pp 1–138, [16]). The airport was commercially operated one year after the new Indonesian Seismic Hazard Maps 2017 released (ISHM-2017). The most important information obtained from ISHM-2017 is the new predicted seismic source located close to the airport area. This paper expresses the seismic hazard analysis (SHA) of the airport area based on the new ISHM-2017. The analysis is performed by conducting three basic SHA steps such as the Probabilistic and Deterministic Seismic Hazard Analysis (PSHA and DSHA), a combination of PSHA and DSHA for developing Most Considered Earthquake Risk (MCER) spectral acceleration and the final analysis is related with the calculation of surface spectral acceleration for developing design spectral acceleration (DSA). The new DSA is then compared to the previous DSA developed based on SNI 1726:2012 (SNI 1726:2012 in Seismic resistance design codes for building and other structures, Jakarta, pp 1–138, [16]) and also compared to the surface spectral acceleration developed using site response analysis (SRA). The result of the study shows that the new DSA has no significant differences and improvements compared to the previous DSA (SNI 1726:2012 in Seismic resistance design codes for building and other structures, Jakarta, pp 1–138, [16]) and SRA results.

Windu Partono, Masyhur Irsyam, I. Wayan Sengara, Asrurifak, Frida Kistiani, Undayani Cita Sari, Haryadi

Morphometric Analysis of Galal Bedrah River Basin Using STRM (DEM) Data and GIS Techniques

A morphometric analysis of Galal Bedrah river basin was carried out by several processes that take place on STRM DEM (Shuttle Rader Topography mission), thereby employing the Spatial Analysis tool in Arc GIS (version 10.5) software for analyzing the study area. Primarily, the Arc GIS software was the basic tool used for extracting the river Basin as well as its drainage network. Upon analyzing, the drainage network was classified using Strahler’s System for classification, which in turn reveals that the drainage pattern is almost dendritic, with the basin order being fifth-order. The study further evaluates the morphometric parameter and its influence on soil physical, landform, and other hydrologic characteristics. The mean bifurcation ratio (Rbm) was found to be 2.35 that have a strong effect on the runoff and its intensity, high relief value, drainage density, and stream frequency. All these values indicate that the basin exhibits erosion and sediment transfer and play a significant role in different hydrological studies.

Mohammed S. Shamkhi, Atyaf J. Mohson, Tabark J. Abdullah

Determination of Watershed Characteristics Using GIS Technique (AL-Adhaim Watershed in Iraq)

The current research aims to investigate the relief, areal morphometric and linear characteristics of the basin of AL-Adhaim using GIS technique. This method is produced pertinent for the extraction of the basin stream and the drainage networks for basin. Advantageously, this technique saves time, effort and also improves the accuracy of the analysis of its drainage networks. The study depends on the analyses of the Digital Elevation Model of the Basin area taken from SRTM Satellite with a resolution of 3000 cm. Upon analyzing the results obtained from the morphometric analysis for streams, one can classify the basin as sixth stream order, and the watershed can be noted, with mean bifurcation ratio (4.43) which have an effect on runoff. Apart from this, the elongation proportion of the basin is 0.97 that in turn demonstrates that the study area is circularly elongated. Additionally, the drainage texture of the AI-Adhaim watershed is 2.33 which implies that coarse texture. Therefore, the present investigate can prove to be very helpful in planning the management and watershed and other hydrological investigates in the future.

Mohammed S. Shamkhi, Tabark J. Abdullah, Atyaf J. Mohson

Serious Conflicts: A Safety Performance Measure at Signalized Intersections

There is a challenge to identify potential sites for safety improvement in case of shortage in crash data. This study explores alternative method based on traffic conflicts as a surrogate safety measure instead of crash data. The study demonstrates two family major safety assessment streams; three of crash-based methods proposed by Highway Safety Manual and two conflict-based methods. For crash-based methods, Empirical Bayes (EB-method), crash frequency and crash rate measures are used. Conflicts frequency and conflicts rate for two surrogate safety indicators are used in the conflict-based methods, in this study, EB-method is used as a benchmark for comparison. The safety evaluation was performed separately for 9 signalized intersections, the safety measures are estimated and compared through Pearson correlation analysis while hazard location identification results through the use of rank-based mean absolute. Results showed that the serious conflicts frequency as a conflict-based method had a high correlation and a coefficient of 0.986 with the EB-method in the resulting outcomes and performed better than crash frequency method in identifying hazard location when compared with EB-method. Therefore, the serious conflicts frequency can serve as a viable option for safety performance evaluation and hazard locations identification, especially when sufficient crash data are not obtainable.

Raghad Zeki Abdul-Majeed, Hussein A. Ewadh

Improving the Mechanical Properties of Low, Normal and High Strength Concretes

Improvement the mechanical properties (compressive and flexural strength) of low, normal and high strength concrete (LSC, NSC and HSC) was investigated experimentally in this work by used CFRP sheets and steel fibers. The experimental program of this research was consisted of two parts, first part was aimed to evaluate the effect of confinement by CFRP sheets on the compressive strength on the cubes and cylinders, while the second part was investigated the effect of strengthening by CFRP sheets, adding steel fibers and use both on modulus of rupture. Comparison with unconfined specimens, results show that the confinement by CFRP was increased the cube compressive strength about 208, 47 and 27% for LSC, NSC and HSC, respectively, while the increasing in cylinder compressive strength was 216, 64 and 51%. On the other hand, increasing in modulus of rupture for LSC was 373.93, 84.83 and 506.6% for specimens with CFRP, steel fiber and both used of CFRP with steel fibers, respectively. While this increasing for HSC was 575, 128.2 and 725.64% for CFRP, steel fibers and both used of CFRP with steel fibers, respectively. However, for NSC, the percentage of increasing was 455.7, 73 and 605% for the same order.

Yaarub Gatia Abtan, Hassan Falah Hassan

Application of Geographic Information Systems (GIS) in the Multi Criteria Site Selection of Retention Pond for Urban Rainwater Management

This article aims to determine the criteria needed and to create a map of location suitability for the retention pond site selection with the case study in the city of Medan, the province of North Sumatra, Indonesia. The multi criteria decision analysis (MCDA) based on geographic information system (GIS) was applied to reach this goal. Pairwise comparison (PC) method of analytic hierarchy process (AHP) is used to calculate the weight of each criterion and the weighted linear combination (WLC) method applied to combine the criterion or factor maps. All of the data processing and analysis were completed using IDRISI-Selva software version 17, where the final result was a suitability map. Seven factor maps (i.e. rainfall, runoff, slope, aquifer, distance to channels, distance to river, and land use/land cost) and seven constraint maps (i.e. well, road, strategic area 1, strategic area 2, utilities, railway, land use) are established and involved in this site selection model. The obtained suitability map has four levels of suitability, namely low, moderate, high and very high suitable with an area of 0 ha, 379 ha, 12,778 ha and 1291 ha, respectively. The results of this study can be used as input to decision makers in urban areas, especially in terms of selecting the location of retention ponds to improve their rainwater management performance.

Darman F. Saragih, Mohd Sanusi S. Ahamad, Rozi Abdullah

Disinfection By-Products Precursors Removal by Simultaneous Coagulation and Disinfection in River Water

Disinfection in drinking water had significantly reduced the risk of pathogenic diseases but may cause chemical threat to human health due to disinfection by-products (DBPs) formation in the presence of natural organic matter (NOM). In general practice, NOM can be removed by using coagulation process. However, the efficiency of a coagulant-disinfectant mixture as a quick water treatment measure in removing NOM as the disinfection by-products needs to be determined. The main objective of this research is to determine the ability of DBPs precursors’ removal of coagulant—disinfectant mixtures. Selected water quality parameters which are turbidity, UV254 and DOC were tested to observe the DBPs precursors removal when using either ferric chloride (FeCl3) or ferric sulphate (Fe2(SO4)3) as coagulant and either chlorine (Cl2) or chlorine dioxide (ClO2) as the disinfectants. FeCl3 was a better coagulant compared to Fe2(SO4)3 in removing DBPs precursors with percentage of 98.03 and 87.91 removal for turbidity, and UV254, respectively. The combination between FeCl3 and Cl2 resulted in the highest turbidity and UV254 removal, 97.11% and 79%, respectively, while the combination between Fe2(SO4)3 and Cl2 only recorded DOC removal of 25.5% from the water sample.

Nur Izzati Naserun, Nurul Hana Mokhtar Kamal

Underlying Disaster Risk Factors for Sustainable Coastal Development Projects in Malaysia

As disaster threats are inevitable, efforts should be directed to reduce the disaster risks via the implementation of risk mitigation measures to lessen the impacts. Current studies on disaster risks mostly focus on disaster risk reduction along with pre-disaster and post-disaster processes while the study on factors influencing the perception of risks is not sufficiently addressed. This paper aims to investigate the underlying factors that influenced disaster risk perception to ensure effective risk governance for a successful sustainable coastal development projects from the perspective of stakeholders with a credible engineering backgrounds. Analysis of this study is based on a survey conducted among 311 engineering students in Universiti Sains Malaysia (USM) regarding factors considered as part of the risk governance with respect to sustainable coastal development. It was found out that the environmental (92.93%), economic (73.63%) and health and safety (54.98%) factors were considered as the three most important factors by the students.

Sharifah Akmam Syed Zakaria, Mohd Azrulfitri Azimi, Taksiah A. Majid

Exploration of Training and Education for Attaining Disaster Resilience from Sustainability Perspective Among Civil Engineering Students

The engineering profession must be developed in an integrated manner by incorporating the training and education aspects of disaster management to ensure that engineering professionals are able to perform during uncertainties besides being able to continuously elevate themselves to handle disaster risks. While disaster management methods or tools are widely available, much still needs to be done to shape them for disaster education purposes from sustainability perspectives. This paper presents results pertaining to the exploration and classification of major sustainability elements in disaster management education based on a disaster management cycle for attaining disaster resilience among civil engineering students at Universiti Sains Malaysia. Specifically, this paper also outlines research outcomes from the applicability of the disaster management cycle with the focus on prioritizing sustainability elements namely economic, environment, social, governance and technology. Results were obtained using a qualitative method through a scenario evaluation to determine the most significant sustainability elements with respect to training and education of disaster management. It is concluded that sustainability elements particularly on governance (at response and recovery stage) and social sustainability (at mitigation and preparedness stage) are found to be influential in disaster training and education for attaining community resilience in the civil engineering field. The study has also revealed that social sustainability plays a significant role throughout all stages of the disaster management cycle. This study provides an avenue for the integration of sustainability elements into disaster management curricular.

Sharifah Akmam Syed Zakaria, Taksiah A. Majid, Tze Liang Lau, Mohd Azrulfitri Azimi

A Review on the Government’s Way Forward Policy Towards Environmental Sustainability Construction Projects in Malaysia by 2020

Major flood experience in 2014 has served as one of the reminders to the Malaysian government to start building the nation’s resilience towards sustaining the impact of unexpected natural disasters. For that, the Construction Industry Transformation Plan (CITP) 2016–2020 has been established and introduced to shift the construction industry “business as usual” to a more robust “moving forward” approach by focusing on transforming the current construction industry in Malaysia into environmentally sustainable construction industry. The aim of this review paper is to identify the types of natural disasters that commonly occurred in Malaysia as well as programs and initiatives developed by Malaysian government in order to promote and support a comprehensive sustainable construction in the Malaysian practice. It starts by explaining the natural disasters in Malaysia, then followed with the discussion about sustainability journey in the Eleventh Malaysia Plan, and lastly, discussion on CITP 2016–2020. From the review, the commonly occurred natural disasters in Malaysia are floods and landslides which impede the sustainable development in the country. Under the CITP blueprint which forms a part of the recent national plan, the government has shifted its standard, conventional, and costly approach of “grow first, clean-up later” into a greener course of “green growth” to assure that most of the procured development projects are environmentally sustainable. Therefore, instead of making Malaysian construction industry as a world-recognized competitor with the quality, safety and professionalism; environmental sustainability; productivity; and internationalization as the primary thrusts, CITP 2016–2020 also helps to fully transform the construction industry into a modern, highly productive, and sustainable industry by the year 2020.

Nurul U‘lyani Mohd Najib, Farid Ezanee Mohamed Ghazali

Change Order Impact on Construction Industry of Pakistan

Change order is the alteration in the contract documents which signed before a project between two parties. The impact of change order fluctuates the budget as well as the duration of the project. Change order has been called the biggest cause of dispute between the contractor and client. The aim of this research was to find out the factors that cause change order and articulate a guideline to overcome the problems for stakeholders of construction industry. From the perspective of expertise, stakeholders of construction industry and literature review a questionnaire was designed and conducted an exploratory survey. The data collected from 102 respondents were analyzed through Statistical Packages of Social Sciences (SPSS-23) and MS Excel for reliability check. 32 influential factors identified through an exploratory survey from the stakeholders of construction industry. Five factors like scope of the project, defects in drawings, client financial problems and lack of skilled labor and role of technology concluded high-rank factors by Relative importance index (RII). To avoid the adverse effects of these factors and disputes between the different parties, the project scope must be identified from the beginning of the project. The drawings should be cleared to the owner and project should be managed properly. Majority of the projects are affected by the change order, it is therefore suggested to focus on the critical factors to avoid the effects.

Muhammad Altaf, Muhammad Ali Musarat, Azizullah Khan, Zohaib Shoukat, Usman Salahuddin

An Investigation of Causes of Delay Affecting the United Arab Emirates Construction Industry

The construction industry is one of the key elements of the economy; therefore, it has a major impact on the economic development of the UAE. A common problem affecting the delivery of projects (private or public) is delay, which has a significant negative effect on the UAE economy. The objective of this study is to determine the critical delay factors that affect construction projects in the UAE. A literature review was also conducted, in which 106 factors were identified. A structured survey questionnaire was then developed and distributed to experienced engineers working in the UAE construction industry. The top factors that cause construction delay were found to be: changes of orders, clients’ delays in decision-making and approval, financing difficulties of contractors, contractors’ poor site management and poor site supervision, contractors’ poor controls of site progress. These research findings can provide good guidelines to the construction industry to minimize the delay by addressing its causes. The guidelines advise the clients to reduce change order requests and avoid delays in decision making or approval required at any stage of construction; support the contractors in project planning; and prepare the contractors for project risk expected in the project at the planning stage before execution.

Abdulhamid AlGheth, Md. Ishak Sayuti

Effects of Micro- and Ultrafine Metakaolin on Compressive Strength and Water Sorptivity of High Volume Fly Ash Concrete

The experimental study on the effect of using micro- and ultrafine metakaolin incorporated with Portland cement composite for the improvement of compressive strength and water sorptivity of high volume fly ash concrete is presented in this paper. Mixture proportions was prepared where metakaolin in micro- and ultrafine sizes was used to replace cement in high volume fly ash concrete mixtures (40 and 60% by wt.). Phase identification and the hydration products were obtained through X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) analysis. The results reveal that the inclusion of micro- and ultrafine metakaolin offsets the inferior characteristics of high volume fly ash concrete by accelerating the hydration products, contributes the formation of additional CSH through the reaction with calcium hydroxide and densifies the microstructure of sustainable high volume fly ash matrix, particularly at the 7th day after water curing. Furthermore, the utilization of high volume fly ash containing micro- and ultrafine metakaolin is potential for the application of eco-friendly concrete.

Steve W. M. Supit, Febriane Makalew

Review of Delay Causes in Construction Projects

Construction delay is the one of major factors globally which have a high impact in countries’ economy and development in UAE and any other countries. The present paper reports an exploratory research study of previous international research into delay factors affecting project delivery. The objective of this research was to provide a general overview of construction delays in order to recognize the main groups of delays and compare the UAE construction projects with international studies. In total, 14 groups were found to contribute to causing construction delays. Studies of the international and UAE construction industry are in agreement that the main group of factors that affect project completion are management factors; then, the second group comprises financial factors however the top 3 groups in UAE are contractor management group, client financial group and the client management group. In international the top 3 groups are contractor management group, client management group and the third is contractor financial group.

Abdulhamid AlGheth, Md. Ishak Sayuti

The Influence of Type and Combination of Polycarboxylate-Based (PCE) Superplasticizer on the Rheological Properties and Setting Behaviours of the Self-consolidating Concrete Containing GGBS and DSF

This paper is focus on the influence of the type and combined use of polycarboxylate-based (PCE) superplasticizer of fresh properties and the setting behaviour of self-consolidating concrete (SCC) incorporating ground granulated blast furnace slag (GGBS) and densified silica fume (DSF) as primary binder phase prepared at low water-to-binder (w/b) ratio. The MPEG, a fixed dosage of TPEG type of PCE superplasticizer and blend of MPEG and TPEG PCE were used as superplasticizer compound of the HPSCC. The assessment on fresh properties of the HPSCC includes slump-flow test (T500), L-box, and sieve segregation test. In addition, the effect of the various type and combinations of the PCE superplasticizer on the initial and final setting of the SCC were compared. The results obtained indicated that the blend of MPEG and TPEG PCE exhibited negative effect on the fresh properties of the SCC by increasing the water demand to achieve a similar workability as individual use of MPEG and TPEG PCE. Meanwhile, it was observed that the combination of MPEG and TPEG PCE has reduced the retarding effect on the binder phase hydration.

Chow Wee Kang, Cheah Chee Ban, Oo Chuan Wei

Effect of Various Grades of Na2SiO3 on Compressive Strength Development of Eggshells Powder-Based Alkaline Activated Mortar

The effect of various grades of Na2SiO3 on the compressive strength (CS) development of alkaline activated binder mortar (AABM) synthesized from eggshells powder (ESP) with curing time of up to 28 days has been investigated. Three different mixtures of AABM were synthesized from the solid material and alkaline activator solution (AAS). The solid materials consisted of source material and aggregates. ESP was used as the sole source material for the AABM. The AAS was prepared from NaOH and various grades of Na2SiO3 which was characterized by their SiO2/Na2O molar ratio of 2.064 (#1), 2.27 (#2), and 3.3 (#3), respectively. The results showed that the mixture prepared with Na2SiO3 grade #1 has a higher CS than the other two mixtures. The highest CS was 12.31 MPa at 28 days. The CS development was associated with the formation of tilleyite phase as gel binder and it is in good agreement with the XRD analysis.

Mohamed O. M. Mashri, Megat Azmi Megat Johari, M. J. A. Mijarsh, Zainal Arifin Ahmad

Numerical Simulation of ISO Freight Container Using Finite Element Modelling

The use of freight container for structural purpose had become trending among housing industry. Its strength in modular, sustainable, build ability and high structural performance makes it a potential option to solve the housing provision issue. Although the strength of standardized freight container had been specified by ISO, its ability for residential purpose is still in doubt. The physical testing of actual freight container can be costly and time-consuming. The objective of this research is to develop freight container model from numerical approach using finite element modelling. Abaqus/CAE was used to model the ISO container and compressive load was applied at each corner. Load-displacement relationship and stress distribution of container model were recorded and compared with previous work. From this research, the current model was able to achieve targeted load and showed similar structural response as previous model.

Philip Chie Hui Ling, Cher Siang Tan

Stability and Overtopping Assessment of Tanjung Piai Stone Revetment via Two-Dimensional Hydraulic Modelling

Over the years, Tanjung Piai in Johore had experienced severe coastal erosion due to dredging of navigation channel and high frequency of wake waves created by growing number of ships using the Straits of Malacca, Tebrau Straits and Port of Tanjung Pelepas. As a result, a stone revetment was proposed and designed by Department of Irrigation and Drainage (DID) to contained and dissipate wave energy at the eroded mangrove area. The aim of this study therefore is to assess the performance of the stone revetment via hydraulic physical modelling. The experiment was conducted in a wave and flow flume, adopting a scaled model of 1:7. The model was tested for stabilities and wave overtoppings under 20 and 100 years Average Recurrence Interval (ARI) wave conditions, as required in the design report commissioned by DID. The results showed no damage criterion and no overtopping occurred under 20 years ARI waves. However, in the case of 100 years ARI waves, damage criterion of Nd = 7.12% and overtopping discharges, Qp = 34.4 l/s/m was calculated, which still falls within the permitted limits.

Mohd Kamarul Huda Samion, Saiful Bahri Hamzah, Safari Mat Desa

Finite Element Analysis of the Effect of Screw Number on the Connection Behaviour for Cold Form Steel Truss Systems

The demand for cold formed steel (CFS) has increased due to its advantages such as lightweight with high strength to weight ratio, easy for transportation, can be manufactured in different configurations and shapes and etc. CFS trusses were frequently used in roof structures in industrial and residential buildings. The function of a truss was to transfer load from point of application to the supports as directly as possible. In this research, the screw connections at the side and peak location of Fink and Howe truss were being modelled using LUSAS. Lipped channel (LCS) and rectangular hollow section (RHS) were selected as material of cold formed steel truss. The aim of this analysis was to investigate the behavior of connection in cold formed steel truss system based on different number of screws. Then the validation was carried out for the finite element analysis results with design checking procedure in Eurocode 3. By modifying the number of screws through finite element analysis, the connection strength based on the results such as displacement, stress, shear and moment were discussed. The outcomes of modelling results show that both types of cross sections gave different performances. The displacement in LCS decreased when more number of screws were added to the connection. Instead, for RHS the displacement increased slightly when the number of screws increased. The principal stress in both cross sections declined when more screws were inserted. Similarly, shear force for both cross sections dropped when there were more screws except for the peak location of Fink truss in LCS where it shows the lowest shear force when one or two more screws were added to the connection. Meanwhile, moment decreased when more number of screws were added. The only increment of moment happened at the peak location of Fink truss in the RHS. It shows that the typical number of screws are sufficient for the connection of Fink truss and Howe truss.

Fatimah De’nan, Kok Keong Choong, Jessica Loo Si Jia, Nor Salwani Hashim

Load-Displacement Behaviors of Reinforced Concrete Beam Embedded with Galvanized Steel Cable: Comparison Between Experiment and Finite Element Analysis

Lightning is a natural phenomenon which occurred when the upper atmosphere becomes unstable due to rising air currents. Lightning can be one of the natural causes of human injuries or damage to electrical equipment. In order to create a system to protect buildings from this natural phenomenon, the Lightning Protection System (LPS) was introduced. However, various problems have been associated with this conventional method. A common problem related to external lightning protection cables is corrosion. Therefore, the newly arrangement of lightning protection cable was proposed and investigated. Galvanized steel cable was used in this research due to suitability of the materials to be embedded inside reinforced concrete beam. Load-displacement behavior from the three (3) point flexural test was compared with the finding from the Finite Element Analysis (FEA). From the result, FEA showed slightly higher than experiment result at the maximum load.

Mustaqqim Abdul Rahim, Abdul Naser Abdul Ghani, Muhamad Arkam Che Munaaim, Zuhayr Md Ghazaly

Effects of Nano-silica on Concrete Properties—Literature Review

This paper is a reviewing study about the use of Nano silica as an additive or a cement partial replacing material to enhance most of concrete properties. Due to their ability to fill even in extremely small voids and their pozzolanic reactivity, silica nanoparticles were found to effectively modify concrete microstructure into refined denser system. They considerably improve the cement-aggregate Interfacial transitional zone by filling the voids, consuming CH crystalline particle and producing more CSH gel. These modifications are presented as SEM images, XRD and thermogravimetric TG graphs as reported by the researchers. Through the microstructure improvement, NS was found to enhance most of concrete mechanical and durability properties. The effects of incorporating NS on concrete compressive, flexural and tensile strengths, water permeability, sulfate resistance and resistance to chloride permeability were reviewed and discussed. Effect of NS on fresh concrete workability and setting time were also studied.

Khaldon Kasim Aswed

Economic and Environmental Assessments for Constructing New Roads: Case Study of Al-Muthanna Highway in Baghdad City

The geographical area of this study located between the Army canal and Al-Sadr City is characterized by high-density population and lack of high-speed highways. This area is facing a low service level during traffic congestion resulting from an inefficient and poor road network. A traffic study has been done which recommended the construction of a new road parallel to the existing one, but with higher standards. This research aimed to evaluate, economically and environmentally, the feasibility of constructing a road for Al-Muthanna highway. This research is based on the hypothesis that the present road exhibits a relatively severe condition whereas the suggested road will be an asphalt pavement with a high-quality status. The traffic volume data was collected using a manual counting method for seven days from 7:00 am to 4:00 pm to quantify the average daily traffic and peak hour volume. In addition, the number of lanes required for LOS (C) was determined. The construction and maintenance costs for the road were also calculated. Reduction in road user costs for both the present and proposed roads were estimated as advantages. The economic study is done by balancing the reduced total road costs and their advantages to the basic year. The assumed discount rate in this study was 8%. To discover the economic viability, various standards were verified. These standards are Benefit–Cost Ratio (B/C), Net Present Value (NPV), and Internal Rate of Return (IRR). The outcomes revealed that NPV exhibited an encouraging value, that indicated that total benefits were larger than costs. Moreover, the B/C ratio was found to be more than 1.0, which was promising. Lastly, the IRR was found to be greater than 8% as suggested in the road projects.

Qais S. Banyhussan, Sady A. Tayh, Ahmed M. Mosa

Effect of Semi-rigid Connection on Post-buckling Behavior of Braced-Steel Frames

Practically, rigid beam-column connection has a relative flexibility which reduces their resistance to moments and this lead to partially restrained connection which is called semi-rigid connection. This research presents a numerical analysis using finite element method by ANSYS software to predict the effect of semi-rigid beam-column connections on post-buckling behavior of braced and unbraced frames and make a comparison between them. The beam and column of the frames were modeled using beam element and the semi-rigid connections were modeled as rotational springs with different rotational stiffness values in linear elastic stage. The results show that, the load-displacement curve of the braced frame is less affected by changing the beam-column connection from rigid to semi rigid with different rotational stiffness values as compared with that of the unbraced frame although this changing has slight effect on the ultimate vertical displacement. Also the results show that the semi-rigid connection should be take into account in analysis and design of braced and unbraced steel frames to obtain more realistic results.

Douaa R. Mohammed, Murtada A. Ismael

Critical Transformational Time of Ground Level Ozone from Nitrogen Dioxide in Urban Area

The prior aim of the study is to investigate the characteristic of the ground level ozone from its main precursor during critical transformation time in urban area. The analysis was carried out using the dataset of three selected urban area from 2013 to 2014. The mean O3 concentration recorded throughout 2013 and 2014 in Kota Bharu, Putrajaya and Shah Alam is 15.56 ppb, 21.34 ppb and 19.17 ppb, respectively, while the mean O3 concentration during critical transformation time (CCT) is 13.07 ppb, 13.51 ppb and 12.14 ppb, respectively. It has been found that the O3 concentration is high starting from March to May due to the Southwest monsoon season in Putrajaya and Shah Alam. However, O3 concentration in Kota Bharu is recorded to be the highest starting approximately from May 2013, while in 2014, the O3 concentration is high starting from January to February, then from April to August. The CCP was observed to be occur within the CCT, between 8.00 a.m. and 11.00 a.m., using the diurnal plot and the O3 maxima was observed, usually after CCT at approximately 2.00 p.m. to 4.00 p.m. The finding clearly showed that the CCT period is an important period in O3 daily fluctuation that should be given more attention to understand this air pollutant.

Hasifah Abdul Aziz, Wai Wei Khong, Norrimi Rosaida Awang, Arni Zulaikha Ismail, Nur Syifa Adnan, Wan Noor Syaheerah Wan Yuzamree, Amni Umirah Mohd Nazir

Bus Passenger’s Satisfaction on Accessibility to AmanJaya Bus Terminal: A Gender Comparison

A quantitative gender-based study was conducted to investigate the satisfaction levels of bus passengers towards accessibility to AmanJaya Bus Terminal, Perak. The assessment was performed based on 734 questionnaires distributed across different representative groups and the descriptive analysis proved that both male and female passengers were satisfied with the travel distance, travel time, travel cost and overall accessibility to the terminal. However, the differences in the satisfaction level shows that the respondents were reluctant to consider the accessibility to the terminal as very satisfying. Statistical analysis found that cost exhibited a significant effect on the overall level of satisfaction. Furthermore, group statistics of gender and satisfaction variables revealed that the mean value of male respondents for cost is higher than female attesting that cost is being more prioritized by men compared to women.

Siti Fadhlina Muhammad Fisal, Nur Sabahiah Abdul Sukor

Best Position of Pile in Earth Slope

Many researches have tried to specify the best position of pile to stabilize the earth slope. This article investigates the best position of pile on earth slope despite different results obtained from previous researches. Slope crown, downslope and middle of slope are positions obtained by researchers for installing the pile on earth slope. Limit analysis (LA), limit equilibrium method (LEM), experimental and finite element (FE) methods have been used for finding the best position of pile. This article investigates a solution to unify the results of entire methods and finding the best position for installing the pile. The results of all methods comply with another and present a unique failure mechanism. The experimental and FE methods indicated that the best pile position in cohesion less soils is at the middle of slope; and the best position in cohesive soils is in the one-third middle area. It can be concluded that the near to XF/LX = 1/2 of slope is the best location for installation of pile.

M. Hajiazizi, F. Heydari

Relation Between Surface Preparation and Corrosion Resistance in Painted Steel Sheets

The surface of a painted steel material is periodically repainted to maintain its corrosion resistance by removing the rust and remaining paint films on the steel sheet using surface preparation. However, there are several unknown factors governing the relation between the surface state of steel sheet and its corrosion resistance. This study aims to investigate the effect of surface preparation on the corrosion resistance of a steel sheet. Herein, three types of steel sheets treated with different surface preparations were painted and their corrosion resistances were investigated by combined cyclic corrosion tests. The differences in the corrosion resistance among the painted sheets were investigated from the viewpoint of the surface free energy. Results show that the corrosion resistance of a painted steel sheet prepared using a zinc-plated steel wheel wire brush is better than those for a steel wheel wire brush and nickel-plated steel wheel wire brush. This finding suggests that the difference in the corrosion resistance based on the plated metal arises from the polar components at the steel surface.

H. Kobayashi, K. Morita, Y. Yamashita, Y. Kataoka

Application of a New Concept of Cracked Soils in Slope Stability Analysis with Heavy Rain and the Pattern of Cracks as the Governing Factors

The results of slope stability analyses in a new construction area at the State Polytechnic of Balikpapan, Indonesia revealed that the slopes are all in a stable condition with a safety factor (SF) greater than 1, even when the slopes were assumed to be fully saturated. However, in reality the slopes had been sliding and creeping downward, especially when heavy to very heavy rain occurred. The slope movements had caused severe damage and destruction to parts of the surrounding structures. This phenomenon of contradiction between geotechnical analysis and field conditions would not have occurred if the new concept of cracked soil was used. In the concept of cracked soils, heavy to very heavy rains and the crack patterns are the governing factors for slope stability. The results of the re-analysis, conducted with the new concept of cracked soils, reveal that the slopes are indeed sliding and unsafe (SF < 1). Therefore, the new concept of cracked soils is a more appropriate method for slope stability analysis.

D. Amalia, I. B. Mochtar, N. E. Mochtar

Characteristic Study of Physical and Chemical Properties of Limestone Subjected to Adsorption of Fe and Mn in Groundwater

Understanding the characteristic of adsorbent media is important to assess their compositions, particle size, morphology and the functional group. In this study, limestone was selected as adsorbent media in removing iron (Fe) and manganese (Mn) in groundwater. The characteristic of limestone was analysed using XRD, XRF, FTIR, FESEM and surface area analyser. Analysis on minerals composition detected that limestone that has been used in this study contain major portion of CaCO3 (97.91%) and can be classified as high purity limestone. Based on the FTIR analysis of the raw limestone, it shows that the presence of hydroxyl group with O–H stretching is a favourable group of Fe and Mn adsorption. In addition, some crack between calcites connection and voids were found on the SEM image of raw limestone sample. Comparatively, the surface morphology of limestone after adsorption process presented that more crystal grains (ferrihydrite particle) were completely covered to the surface of limestone. A new manganese oxide (MnOx) also appeared at 585 cm−1 through Mn stretching, proving the occurrence of Mn adsorption process in groundwater. Therefore, limestone has the capability to remove Fe and Mn for groundwater and provide good filter media for heavy metal groundwater treatment. Due to the superior characteristic of limestone, this media offers a good alternative for Fe and Mn removal in groundwater.

N. A. Akbar, H. A. Aziz, Mohd Nordin Adlan

Rice Husk Ash Derived Sodium Silicate Using Hydrothermal and Convection Heating Methods

Geopolymers produced by using waste materials are more cost-effective and environmentally friendly. Commercial sodium silicate (sodium water glass) is currently being produced by direct fusion of pure silica sand and soda ash (Na2CO3) in oil, gas or electrically-fired furnaces at high temperatures (~1300 °C)—a production process that is energy intensive and which generates CO2. One method of minimizing these environmental issues is to use supplementary sources of silica, such as rice husk ash (RHA), to produce sodium silicate at lower temperatures. Therefore, this project aims to compare the effect of sodium silicate solution made of rice husk ash sieved at various particle sizes (un-sieved, <45 μm, <300 μm) using two techniques of (a) hydrothermal and (b) convection heating on fly ash-based geopolymer mortars. The geopolymers synthesized using ‘in-house’ sodium silicates were then compared with those made using commercial sodium silicate. Physicochemical properties of raw RHA and synthesized sodium silicates were characterized using the Energy Dispersive X-ray Fluorescence Spectrometer (EDXRF), X-ray Powder Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Field Emission Scanning Electron Microscope (FESEM), Energy Dispersive X-ray (EDX), and Inductively-Coupled Plasma (ICP). When using the convection heating method, finer particle sizes resulted in a higher conversion rate, while finer RHA resulted in the precipitation of crystalline silica during the hydrothermal process. Geopolymer mortars cured at a temperature of 70 °C were tested for compressive strength at 1, 7 and 28 days. At lower alkali dosages, the mortar strengths made out of both in-house and commercial sodium silicates had comparable strengths, while at higher alkali dosages the mortars prepared from commercial sodium silicates demonstrated significantly higher strengths.

Tze Jhin Tsen, Daniel Kong, Ehsan Zeimaran, Marios Soutsos

Influence of Twin Tunnel Depth in Numerical Ground Movement Prediction Using Mohr Coulomb and Hardening Soil Model

In urban area tunnel construction growing rapidly due to urbanization and increase in population rate. Tunnels are excavated at different depths from ground surface, but this will cause ground settlement in the excavation area which impact the surrounding structures. This paper is focused on effects of the surface ground movement prediction using numerical approach at various depth with Mohr Coulomb (MC) model and Hardening Soil (HS) model. Kenny Hill Formation used as the study area particularly chainage NB 1960. In this paper, the shape and pattern of the ground movement that obtained from simulation in PLAXIS 2D using MC model was compared with HS model output. Various tunnel depth location was used in the analysis such as real site condition tunnel depth and the relationship of 1d, 2d, 3d and 4d where d is the diameter of the tunnel. From this study, it can be seen that when tunnel depth increases the surface settlement decreases for both MC and HS model. But, the MC model’s ground surface settlements were undoubtedly lower than HS model.

Darvintharen Govindasamy, Mohd Ashraf Mohamad Ismail, Mohd Faiz Mohammad Zaki

Issues and Challenges Encountered by Project Managers Towards Small Public Construction Project Success in Malaysia—A Literature Synthesis

A growingly competitive landscape and demands for better quality government services have characterised new issues and challenges arising from various factors in construction project management. The balance and progress of a country based on project development. It can be observed through every budget allocation that focuses heavily on high impact and touch points projects to the people. This applies to the management of a small public construction project, where the project manager is an important factor in determining the success of a project in the field. Therefore, the failure to manage public project development will have a major impact on the effectiveness of national development. The purpose of this paper is to highlight the issues of managing small public construction projects towards achieving project success which often executed in different perspectives governing the work by project managers. The data for this study were supported by previous studies are reported in the journal; statistic report from CIDB; ICU JPM; KKLW; book and internet sources. As such, the analysis and synthesis of the literature on issues and challenges of the small public construction project is utilized as the basis of future research to establish a general guideline that provides information on managing the small public construction project for Malaysian project managers successfully.

Syaharudin Shah Mohd Noor, Muneera Esa, Ernawati Mustafa Kamal, Rahimi A. Rahman

The Effect of Ozonation By-products on Human Embryonic Kidney Cells (HEK293): Ozone as Wastewater Treatment Tool

The occurrence of the pharmaceuticals and personal care products (PPCPs) is found daily in the wastewater stream since these micropollutant never removed by the conventional wastewater treatment. The daily accumulative of PPCPs in human and aquatic life can cause health and genetic damage, for that using an advanced oxidation treatment like ozone is necessary to remove the PPCPs from the water, the ozonation by-products have been studied to ensure the safety of using ozone as a polish step to remove the PPCPs from the water stream. This study shows the effect of the ozonation by-products on the human embryonic kidney cells HEK293 proliferation comparing with the control. Results shows that the ozonation by products are safe and most of the by-products are weak acids compounds that can be degraded in sun light and cell proliferation reduction were no more than 10% comparing with control, for that ozonation by-products are safe for human.

Hind M. Ewadh, Siti R. Sheikh Abdullah, Nurina Anuar

Comparison on Total Weight of Steel Reinforcement for 5 Story Reinforced Concrete Building with and Without Seismic Design

On June 5th 2015, Malaysia was shocked by an earthquake with Mw6.1 which had struck Ranau, one of the districts in Sabah. The moderate earthquake was the strongest recorded since the Mw5.8 earthquake which occurred in Lahad Datu in 1976. The Ranau earthquake had caused minor to severe damages to local buildings. Although Sabah is located outside the Pacific Ring of Fire, there are some regions which set at risk of earthquake namely as Kundasang, Ranau, Pitas, Lahad Datu and Tawau. After experiencing the tremors from both local and regional earthquakes, Malaysian now aware on the importance of seismic design on buildings and structures. However, the effect of seismic design application on cost of materials need to be studied beforehand. In relation to that, this study presents the seismic design of reinforced concrete hotel or dormitory building with consideration of different magnitude of reference peak ground acceleration, αgR and different soil type. Result shows that both parameters strongly influencing the cost of steel reinforcement. The latter is estimated to be increase around 14–247% higher compared to similar building without seismic design.

Mohd Irwan Adiyanto, Nur Hazwani Mohd Rashid, Syed Abdul Haris Syed Mustapa, Noram Irwan Ramli

Comparison Between the Constraints of Building Information Modelling (BIM) and 3D Modelling

This new emerging and innovative concept of Building Information Modelling (BIM) has delivered changes in terms of the efficiency and effectiveness of management in the construction industry. However, several constraints in the implementation of BIM are indicated notably people, process and technological constraints. In Malaysian quantity surveying profession, several quantity surveying firms are developing 3D model for taking-off and cost estimating preparation based on the standard method of measurement owing to the infancy stage of BIM implementation. This is still not a conventional work task in the quantity surveying profession. To promote the usage of 3D modelling which is far different compared to the traditional method, it is crucial to understand the constraints of 3D modelling and BIM. Therefore, this paper aims to compare the constraints of BIM and 3D Modelling in quantity surveying profession. Eleven semi-structure interviews have been conducted with the experienced quantity surveyors who are practising 3D modelling for quantities and cost estimation purposes to collect experts’ comments on the constraints of 3D modelling compared to BIM implementation. The content analysis which focuses on describing and quantifying phenomena is selected as a research analysis method for the diverse empirical data. The research finding indicated that technological constrains are significantly affecting the 3D modelling implementation while people and process constraints are less significant. This research finding serves as a guidance for quantity surveyors who are willing to take initiatives in implementing 3D modelling in quantity surveying profession.

Lam Tatt Soon, Hasnanywati Hassan, Nazirah Zainul Abidin

Influential Safety Performance and Assessment in Construction Projects: A Review

In construction industry safety issues are the major concern for the stakeholders due to its hazardous nature as it causes injuries and losses of lives to workers. A lot of safety mitigations have been taken but still, the fatalities in construction projects are increasing day by day. The focus of this theoretical review is to underline the critical factors causing poor safety performance in construction projects. The review was carried out in two phases. In the first phase, critical factors causing poor safety performance were highlighted. Besides emphasizing the critical factors, other studies have been reviewed in the second phase where various methods and techniques have been highlighted as safety assessment tools to knob the accidents at the earliest stage of the project. The key findings of this review paper are the main critical factors which influence the construction safety and the developed techniques to enhance the project safety performance. By focusing on the issues and available solutions, stakeholders can bring betterment into their projects.

Wesam Salah Alaloul, Muhammad Ali Musarat, M. S. Liew, Noor Amila Wan Abdullah Zawawi

The Impact of Road Alignment Toward Road Safety: A Review from Statistical Perspective

Road safety is a major issue and a significant global concern. Road accidents have created severe economic and social risks. The analysis can therefore significantly improve the safety performance of the alignment consistency. This paper aims to review briefly the effect of the alignment elements from previous studies on road safety. It includes an explanation of the statistical models used to review the impact of road alignment on accident of roads. Two regression models; linear regression and Poisson regression have commonly developed in previous studies to reveal the effect of independent variables on road safety. Negative Binomial Regression has, meanwhile, been commonly used to highlight the relationship between horizontal alignment and the rate of accidents. The results of the statistical models can also be concluded that road accidents can be reduced by improving road alignment.

Shatha Aser Aldala’in, Nur Sabahiah Abdul Sukor, Mohammed Taleb Obaidat

Pedestrian Walkability Index for Light Rail Transit (LRT) Stations in Klang Valley, Malaysia

Light Rail Transit (LRT) is one of the sustainable transports which is highly promoted by Malaysian government with the intention to ease traffic congestion. However, it is observed that a few of LRT stations in Klang Valley are underutilised and have lesser amount of user. Location of the stations should not be a reason for this as they are usually strategically located and designed to encourage their surrounding residents to commute by walking. Instead, inadequacy of proper pedestrian infrastructure and facility is considered as one of the main factors that affects the commuters’ choice when choosing their mode of transport. The infrastructure design and facility can be measured and evaluated with the Pedestrian Walkability Index. This paper introduces the concept of Pedestrian Walkability Index as a measurement tool for pedestrians’ mode of choice. A new assessment form was created and customised for this purpose by adopting the Krambeck’s Global Walkability Index. Subsequently, three LRT stations were reviewed based on this assessment form and the results for each LRT station were presented. Results showed that Station Asia Jaya has the highest Walkability Index (3.36), followed by Station Sri Rampai (3.15) and Station Miharja (3.08). Results also showed that as the Walkability Index increases, the amount of pedestrian increases as well. The equation for the Pedestrian Conversion factor was found to be y = 9266.5x − 28,014. This can be used as a guide for future LRT station refurbishment project as well as new train station development projects.

Steuart Jia Yun Chin, Boon Hoe Goh, Fang Yenn Teo, Byung Gyoo Kang, Choon Wah Yuen

Seismic Performance of Reinforced Concrete Residential Building Modeled Using Ruaumoko2D Program

Earthquake is one of the natural disaster that cannot be avoided and could give great impact to the world and living things on it. Malaysia is located nearby two seismically active plate boundaries which are between Indo-Australian and Eurasian Plate on the west and between Eurasian and Philippine Plate on the east. Earthquake that happen along these boundaries could cause tremors in Malaysia. East Malaysia especially Sabah also experienced earthquakes from nearby countries. However, Peninsular of Malaysia is considered as low seismic region in Asia. Therefore, majority of buildings in Peninsular Malaysia had been designed by using British Standard Code of Practice which lack of seismic detailing and inadequate consideration of seismic loading during the design process. To secure the human life and increase the building safety, this study aimed to model the structural damage and assessing the seismic performance of five-storey reinforced concrete residential building located in Pulau Pinang, Malaysia which is still in the stage of planning, when subjected to peak ground acceleration of 0.12 g by using Ruaumoko2D and its associated program. The modeling results showed that the structural damages would occurs at the ground and first floor beam-column joints. The displacement ductility valued below 2 proved that the prototype building is vulnerable when subjected to seismic excitation. The maximum lateral strength, maximum lateral displacement and stiffness of the prototype building were also discussed in this paper. The findings of this study could help the engineer to make further improvement by incorporating seismic factor in the building design.

A. G. Kay Dora, J. Mohd Safwan, J. Nurjuhanah, R. N. Mohamed

Oil Palm Frond (OPF) Based Activated Carbon for Leachate Treatment

This research focuses on the application of activated carbon made from oil palm frond (OPF) to treat landfill leachate. The studies were performed in batches to investigate the effect of adsorbent dosage and contact time in removing COD, color, and iron (Fe) from Pulau Burung Sanitary Landfill (PBSL) leachate. Significant parameters such as COD, colour, and iron (Fe) were measured using the USEPA Digestion Method, Platinum-Cobalt Standard Method, and Atomic Analyzer Spectroscopy (AAS), respectively. The chemical and physical characteristics of the f the adsorbent were determined by Scanning Electron Spectroscopy (SEM), Elementary Diffraction X-ray (EDX), Brunauer–Emmett–Teller (BET) and Fourier Transform Infrared (FTIR). Results obtained shows the presence of nanopores (412.1–994.6 nm) and oxygen elements (16.76%) on AC’s surface. BET and micropore surface area were 1357.258 and 384.621 m2/g respectively, while pore volume was 0.191 cm3/g. Hydroxyl functional groups were also observed from FTIR analysis. The characteristics of AC prepared resulted in high removal of COD, color, and iron (Fe) were 82.52, 80.25, and 59.25%. This study concluded that AC produced from OPF with phosphoric acid modification is highly potential for adsorption in leachate treatment.

N. H. Adam, M. S. Yusoff, H. Halim

Detecting Seasonal Extent of Inundated Area of River Body in Banyuasin Regency Using Radar Data of Sentinel-1A

Analysis of Synthetic Aperture Radar (SAR) data from satellite imagery has become preferable by enhancement of its technology, reliable temporal and spatial resolution, computational power and extensive area of coverage. This paper presents the use of SAR data to map the extent of the inundated area of the river as the primary access way in Banyuasin Regency for water transportation. In this study, 1-year data set of Ground Range Detected (GRD) type radar data from Sentinel-1A’s mission was used and analysed by using the Science Toolbox Exploitation Platform (SNAP) toolbox. Related factors on a diurnal tide of river water level and climate which controls the inundated area located mostly within lowland and the biannual season were taken into consideration in the selection of the data set. It is found that the extended inundated area of water body clearly detected. The enhanced polarisation index (VHdB*) which was developed have given a better insight for a response on the extent of inundated area and siltation caused by erosion and sedimentation.

Fathoni Usman, Erwin Ibrahim

Use of Wheat Germ and Chitosan as the Natural Coagulant in Oleochemical Wastewater Treatment

Malaysia’s oleochemical processing industry uses crude palm oil as the main source of process feedstocks. Physical–chemical treatment methods such as coagulation and flocculation processes are widely used to pre-treat oleochemical effluent followed by biological treatment to meet Standard A/B as required by the Department of Environment (DOE). Established chemicals that are used include aluminium sulphate and iron chloride as coagulants while the aluminium chloride, iron salts, and polyelectrolytes are used as flocculants. The industry is in constant effort to look into alternative chemicals that are friendly to both human and environment. Natural coagulants such as wheat germ and chitosan are proposed to treat the effluent. The investigations related to the removal rate of turbidity and chemical oxygen demand (COD) between natural and chemical coagulants were carried out. The effluent samples were analysed with the aluminium content. The results showed that the optimum dosage of wheat germ, chitosan, aluminium sulphate and iron chloride were: 2000, 20, 167 and 169 mg/L respectively. The turbidity reduction efficiency percentage using the wheat germ, chitosan, aluminium sulphate and iron chloride were reported at 80.2 ± 30.2, 78.8 ± 32.9, 96.2 ± 2.0 and 90.3 ± 3.9% respectively. The COD reduction efficiency by using wheat germ, chitosan, aluminium sulphate, and iron chloride were reported at 11.4 ± 5.8, 15.7 ± 6.6, 15.7 ± 3.1 and 15.9 ± 3.3% respectively. The findings showed that the effluent samples from natural coagulation process contains of lower aluminium concentration (0.1 ± 0.1 and 0.2 ± 0.1 mg/L) as compared to effluent samples from chemical coagulation process with the aluminium concentration of 2.4 ± 0.4 and 5.5 ± 0.3 mg/L. Thus, the use of wheat germ and chitosan are less hazardous to human health and environment.

Chee Ming Choo, Kiat Wei Tok, Fang Yenn Teo, Chien Hwa Chong, Vui Soon Chok, Mohd Fariz Majid

Strength and Quality Assessment of Recycled Aggregate and Crumb Rubber Concrete Using the Ultra Pulse Velocity Method

This study focuses on the strength and quality of concrete incorporated with recycled aggregate and crumb rubber through the compressive strength test and the Ultra Pulse Velocity (UPV) test. RA was used to replace coarse aggregate while CR was used to replace fine aggregate in concrete production. A total of 36 specimens consisting of cubes (100 mm × 100 mm × 100 mm) with partial replacements of 50% RA and 0, 1, 2, 3, 4, and 5% CR were prepared, subjected to water curing for 7 and 28 days and tested in terms of compressive strength and quality using the compressive strength test and the UPV method. The UPV test and the compressive strength test were conducted at day 7 and day 28. The results show that the compressive strength of concrete decreased slightly with the increase of rubber content. Additionally, the quality of concrete slightly decreased as the percentage of rubber content increased. Finally, the optimum percentages for partial replacement of concrete suggested based on the results are 3% CR and 50% RA as this concrete mix achieved the highest velocity in the UPV test and the highest compressive strength compared to the control mix.

Mohd Ridhuan Ramlan, Shahiron Shahidan, Sharifah Salwa Mohd Zuki, Siti Radziah Abdullah, Mohd Haziman Wan Ibrahim, Mustaqim Abdul Rahim

Experimental Study on the Polyvinyl Chloride (PVC) Tubes Filled with Concrete Containing Recycled Concrete Aggregate

Recycled concrete aggregate filled tubes (RCFT) is one of the composite columns that has a good potential to be applied in the construction. A polyvinyl chloride (PVC) is utilised as the column skin and it is filled with recycled concrete aggregate (RCA). This concept has evolved from the use of concrete filled tubular members. This study demonstrates the experimental investigation of RCFT acting as columns in compression incorporating varies percentages of RCA. The size of RCFT employed in this study is 300 mm in length and 150 mm in diameter. The ultimate compressive load are determined in this study and compared with the theoretical values. Axial shortening in the RCFT specimens are also investigated. It is observed that the experimental ultimate compressive load, Nexp, is higher than theoretical ultimate compressive load, Ntheo, as per EC4. Lower percentage of RCA resulted in the increment of ultimate compressive load. From this study, the RCFT shows a good potential to be utilised as a composite column system especially in structure with low load bearing capacity.

LynDee Goh, Clotilda Petrus, Mimi Aznira Mohamad

Carbon Footprint Analysis of Industrialised Building System in Malaysia

The topic on sustainability of Industrialised Building System (IBS) in the construction industry of Malaysia is always debatable and questionable. This study is carried out to determine the carbon footprint of a typical commercial project with the application of IBS. In this paper, IBS is classified to aluminium formwork system and fully precast concrete structure. The carbon footprint is quantified with life cycle assessment (LCA) of the building dividing into production phase of materials, transportation phase and construction phase. Whereas the study adopted data of embodied carbon of materials and carbon emission factor from reliable external source to estimate the total carbon emission of the project with the application of IBS. The outcome of carbon footprint is compared with conventional building method to identify the sustainability of each building method. Based on the data analysis, the application of precast concrete has the lowest carbon footprint as compared to cast-in situ with aluminium formwork and timber formwork. Although the carbon emission from the transportation of precast concrete elements is relatively high, but the overall carbon footprint is still the lowest among the other building method. The amount of carbon emission of the commercial project with IBS construction is 0.342 tonnes $${\text{CO}}_{2}$$ per meter square. The production of construction materials that contributed the most to the carbon footprint is concrete, followed by steel rebar and formwork. The findings in this study is very useful for future research on carbon footprint of construction in Malaysia. The study also helps to raise awareness towards sustainable construction with the application of IBS in Malaysia.

Yih Yoong Lip, Fang Yenn Teo, Ioannes Yu Hoe Tang

Parameter Optimization of Conceptual Tank Model for Groundwater Level Prediction

Groundwater is regarded as one of the critical factors that can affect slope stability. Thus, groundwater levels may render useful information regarding the stability conditions of a slope. This preliminary study focused on developing a simple and quick analytical tool to evaluate the groundwater levels due to rainfall for slope stability assessment. To achieve this objective, a well-established rainfall-runoff model known as tank model was adopted in this study. An instrumented soil slope located in Malaysia was used as the case study to investigate the effectiveness of the proposed approach. Rainfall and groundwater levels data for a period of 8 months were used to calibrate the tank model unknown parameters representing runoff, infiltration, groundwater flow and head. The tank model was able to produce a satisfactory root mean square error (RMSE) of 0.185 for the computed groundwater levels compared to the observed groundwater levels. To produce a more accurate prediction, it is recommended to utilize the multi tank models that are position at crest, middle and toe of the slope. An accurate groundwater levels prediction will contribute to a reliable slope stability analysis which is valuable for the landslide early warning system applications.

Soon Min Ng, Mohd Ashraf Mohamad Ismail, Ismail Abustan

A Feasibility Study of Stormwater Management for a Campus University in Semenyih, Malaysia

Sustainable stormwater management is one of the techniques used for managing water runoff as a measure to minimize the consequences of peak discharges, extension of flooding, and deterioration of surface water due to land use changes. The best management practices (BMPs) of sustainable stormwater management endorsed a more effective and environmentally storage-oriented approaches which focus on detention, retention, and recharge in terms of water quantity and quality control. This study has established the information on hydrological parameters and estimations of the existing water conveyance system in a campus university in Semenyih, Malaysia. Based on the hydrological analysis, a thorough review into the BMPs has been carried out. The study presents a proposed stormwater management solution towards the prevention of flash flood in the study area. Wet detention pond has been selected as the BMPs and introduced in the proposed stormwater facilities for quantity and quality control measures. The hydraulic analysis were performed on the proposed solution by referring to the guidelines depicted as in Urban Stormwater Management Manual for Malaysia (MSMA). From the results, the proposed wet detention pond can cater with a maximum storage of 18,579 m3. The pond can handle a surge of floodwater to prevent the backflow of water in the existing drainage system. The two outlet structures of the wet detention pond are able to drain the stormwater runoff at a peak discharge rate which is lower than the pre-development peak discharge rate. The results also revealed that the proposed solution is adequate to cater for the 100-year average recurrence interval (ARI) storm events.

Ming Yuan Ting, Fang Yenn Teo, Ivan Kwong Hieng Theng, Boon Hoe Goh

The Evaluation of Changes in Camber Position to Deflection of Arch Steel Bridge in Extreme Loads

Visualization of the camber position, which has a negative value on the steel frame arch bridge causes user inconvenience and can even lead to a collapse hazard. Siak III Bridge is a national steel frame arch bridge as access between Pekanbaru City and other cities in Sumatra. Based on visual observations, the camber position has a negative value. Monitoring in the form of direct measurement of the bridge center coordinates using a total station tool to show that the camber decreases from the proper condition of the bridge coordinates. Purpose of this study to evaluating the performance bridge structure due to the combination load during the service life of the structure. Therefore, the methodology carried out was to analyze the performance of the bridge based on the model adopted from the 3D bridge and focused on bridge deflection. The analysis is carried out to estimate the deflection ratio of the bridge due to the load and to obtain critical conditions of the bridge structure. The deflection study uses Finite elements with SAP 2000 software. The results showed that based on the maximum deflection value caused by loading (SNI) T-02-2016 the condition of the actual bridge model was −196,470 mm at the ultimate load conditions and −185,731 mm under service load conditions. This result is still below the maximum allowable deflection (L/800) of 200 mm. the benefits of this research can be an input for the government and parties related to bridge inspection in providing appropriate assessments for maintenance, repair, and improvement of bridge functions.

Widya Apriani, Fadrizal Lubis, Reni Suryanita, Yohannes Firzal

Determination of Soil Bearing Capacity and Profile Using CAP-SASW Method at Western Malaysian Peninsular

Bearing capacity is one of an important feature in geotechnical engineering and estimated using in situ conventional method. Inherent problem in the method such as relieving of stress during drilling and testing motivates the use of seismic method to provide supplementary small strain parameters in estimating the bearing capacity. This paper presents a non-invasive method which offers sustainable development by utilizing the propagation of Rayleigh waves and thus minimizing cost in site investigation and construction work. Bearing capacity derived from an equation of hyperbolic shear stress-strain model to evaluate the bearing capacity at some of selected sites at western peninsular Malaysia.

A. B. Ramli, N. Kasim, N. N. Ismail, S. L. Ibrahim, Nadiah Md Husain, W. N. A. W. Azahar

Reusable Concrete Debris as Aggregate Replacement on the Properties of Green Concrete

The sustainability of renewable resources is affected by the rapid booming of the construction sector. The massive production of construction and demolition waste by this sector has given drawbacks to the environment as well. An environmentally friendly approach to overcome the disposal of waste materials is via the recycling process. The main objective of this study is to investigate the properties of concrete made by Coarse Aggregate Associated with Concrete Production (CAACP) and Fine Aggregate Associated with Concrete Production (FAACP). Both CAACP and FAACP were obtained from concrete debris from crushed concrete. Some percentage of the concrete debris will be used as an aggregate replacement for concrete production. Six different concrete mixes containing 10, 20 and 30% of coarse and fine aggregate replacement were prepared accordingly. The concrete samples were tested for its strength at 3,7 and 28 days of curing age. The physical properties of the recycle aggregate were also carried out in order to investigate the possible factor that may affect the fresh and hardened concrete. It can finally be concluded that green concrete can be produced by FAACP or CAACP and possibly to produce higher strength compared to the conventional concrete strength.

Nadiah Md Husain, A. A. A. Razak, W. N. A. W. Azahar, K. Norhidayu, N. N. Ismail, S. A. Saad, S. A. Masjuki, S. L. Ibrahim, A. B. Ramli

Experimental Verification of Reinforced Concrete Pile Caps

This paper deals with the experimental verification of the conventional design of pile caps, ACI 318-14, chapter thirteen. Six reinforced concrete pile cap specimens were designed according to the conventional theory, constructed, tested till failure, and then, compared to the theoretical design ones. The six specimens were divided into two groups; group A in which the spacing between piles was 270 mm, and group B; in which the spacing between piles was 410 mm. Every group contained three pile cap specimens, which were; two pile-cap specimens, three pile-cap specimens and four pile-cap specimens. The two pile-caps were 700 mm in length, 270 mm in height and 240 mm in width, while the three pile-caps were 586 mm in length, 270 mm in height and 700 mm in width. The four pile-caps were 700 mm in length, 270 mm in height and 700 mm in width. It is found that the experimental loads were higher than the design theoretical loads by (180–220)%. That takes place because the conventional method deals with Bernoulli region, while the pile cap is deep. In addition, ACI-318 procedures do not take into consideration the longitudinal reinforcement amount and overemphasize the role of the effective depth.

Khattab Saleem Abdul-Razzaq, Mustafa A. Farhood, Ali Mustafa Jalil

Rainfall Intensity (I)–Duration (D) Induced Debris Flow Occurrences in Peninsular Malaysia

This paper evaluates the rainfall-induced debris flow in Peninsular Malaysia from the perspective of rainfall threshold. Eight selected debris flow occurrences in Peninsular Malaysia have been used for this study. Rainfall records are obtained from the nearest meteorological station of Drainage and Irrigation Department and the Malaysia Meteorology Department. In order to determine the reasonable correlation of rainfall with the occurrence of debris flow, the relationship between rainfall intensity (I) and duration (D) has been analysed. Furthermore, to analyze the empirical rainfall threshold, the values of the maximum hourly rainfall intensity and durations that correlate with debris flow have been plotted along with the intensity against duration in log-log graph. Comparison made between the compiled Peninsular Malaysia data and the worldwide threshold value shows that the triggering threshold is mostly higher for the Peninsular Malaysia events. The presence of thicker soil layers are likely the reason of higher thresholds limit, as more rainfalls are required to cause extensive localized failures to occur.

N. Kasim, K. A. Taib, N. A. A. Ghazali, W. N. A. W. Azahar, N. N. Ismail, Nadiah Md Husain, A. B. Ramli, S. A. Saad, S. A. Masjuki, S. L. Ibrahim

Acoustical Properties of Porous Concrete Containing Oil Palm Shell and Vermiculite

Generally, porous concrete is a suitable noise barrier that absorbs sound energy from noise sources and converts it to heat within the voids. This paper investigated oil palm shell waste (OPS) and vermiculite in enhancing the acoustical properties of porous concrete. The objectives of the study were to obtain the optimum OPS replacement and investigate the effects of OPS and vermiculite on sound absorption coefficient (SAC). Initially, three mixtures were developed; a control mix without OPS and mixtures with proportions of 25 and 50% OPS replacement on coarse aggregate. Results indicated that 25% OPS replacement was the optimum mix based on the compressive strength. Furthermore, 10, 15 and 20% of vermiculite were added to the optimum mix. The results also showed that vermiculite caused an increase in porosity, which changed the acoustical performance. Vermiculite reduced SAC at 1000 Hz and increased SAC at 2000 Hz for all specimens. The SAC curve had two peaks with the highest occurring at the first peak at 400 Hz. The additional vermiculite did increase the NRC value of the porous concrete containing OPS up to 0.43.

Z. Jahya, Z. Haron, K. Yahya, A. Z. Awang, M. S. T. Zulkarnain Tahmali, M. S. N. Samsul, M. N. Yahya, A. A. Jailani

The Potential of Pineapple Leaf Fibre as an Acoustic Absorber

This study discussed an alternative material known as pineapple leaf fibres (PALF) as a replacement of synthetic fibres in sound absorber production. The samples were fabricated from two different sizes of PALF, with and without binder of different thicknesses and densities to determine their effects on the sound absorption coefficient (SAC). The performance of SAC was measured by using an impedance tube instrument according to ISO 10534-2. The resulting frequency peak value of PALF obtained was in the range of 1–2 kHz. The results demonstrated PALF as a new hope for environmentally-friendly sound absorption material in replacing synthetic fibres. The PALF was capable of achieving SAC of more than 0.9 on average above 1 kHz by keeping the densities and thicknesses of the fibres under control. Additionally, the acoustic performance of PALF specimens was better than that of synthetic absorbers available in the market. Therefore, PALF is a promising natural fibre that can be potentially used as a sound absorber material.

K. Yahya, Z. Haron, S. N. Shaikh Abdul Hamid, N. Mohd Fasli, E. M. Taiwo

Investigation on Compatibility Property Between Aggregates and Bitumen Modified with Untreated and Treated Waste Cooking Oil

The superior performance of asphaltic concrete exhibited the good adhesion bonding between binder-aggregates interaction in bituminous mixture. However, the issue of compatibility properties in modification of binder with waste cooking oil (WCO) arises since the poor mechanical performance of asphalt mixture is globally recorded thus reflected the weakness of adhesion bonding inside the pavement material. In fact, the potential of high adhesiveness binding properties is affected by the chemical theory which is chemical composition thereby effecting to the surface microstructure arrangement in bituminous mixture. Therefore, it is vital to conduct the morphology and microstructure observation in order to obtain a comprehensive understanding on the behaviour of the internal structure in pavement material that influencing the adhesion performance. The identification of chemical composition is determined by using Gas Chromatography-Mass Selective (GC-MS). Meanwhile, the surface microstructure observation for asphalt mixture is performed with Field Emission Scanning Electron Microscope (FESEM). Results showed that the incompatibility characteristic is revealed based on the GC-MS result, which discovered the identification of polar compounds in control binder and treated WCO while untreated WCO is recognised as a non-polar compound. The FESEM image illustrated that the more compacted structure arrangement existed in treated WCO mixture compared to the control and untreated WCO mixtures.

W. N. A. W. Azahar, R. P. Jaya, N. Kasim, N. N. Ismail, Nadiah Md Husain, S. A. Saad, S. A. Masjuki, S. L. Ibrahim, A. B. Ramli, N. K. Basri

Effect of Sulfate and Nitrate Anions on the Oxidative Degradation of Tetrachloroethylene by Magnetite with Glutathione

This work demonstrates the effect of sulfate $$ {({\text{SO}}_{4}}^{2 - } ) $$ and nitrate $$ {({\text{NO}}_{3}}^{ - } ) $$ anions during the oxidative degradation of tetrachloroethylene (PCE) by magnetite (Fe3O4) with glutathione. The enhanced of oxidative degradation of PCE was achieved due to the presence of $$ {{\text{SO}}_{4}}^{2 - } $$ and $$ {{\text{NO}}_{3}}^{ - } $$ anions to form reactive radicals in the Fe3O4-glutathione system. Kinetic rate constants for the oxidative degradation of PCE were accelerated 1.8 and 2.7 times higher, from 0.020 min−1 in the PCE-Fe3O4-glutathione to 0.036 and 0.054 min−1 in the PCE-Fe3O4-glutathione-$$ {{\text{NO}}_{3}}^{ - } $$ and PCE-Fe3O4-glutathione-$$ {{\text{SO}}_{4}}^{2 - } $$ systems respectively. The experimental results reveal that the oxidative degradation kinetic rate constant of PCE are strongly dependent on the presence of $$ {{\text{SO}}_{4}}^{2 - } $$ and $$ {{\text{NO}}_{3}}^{ - } $$ radicals. Kinetic oxidative degradation rate constant of PCE increased proportionally as the concentrations of $$ {{\text{NO}}_{3}}^{ - } $$ (0.036–0.120 min−1) and $$ {{\text{SO}}_{4}}^{2 - } $$ (0.0540–0.160 min−1) increased from 1 to 10 ppm at pH 7. The significant finding of this study is to provide the understanding of the oxidative degradation of PCE by Fe3O4 with glutathione in hyporheic zone and groundwater containing the $$ {{\text{SO}}_{4}}^{2 - } $$ and $$ {{\text{NO}}_{3}}^{ - } $$ anions for the development of novel remediation technolojgies.

Nur Dalila Mohamad, Amnorzahira Amir

Low Carbon Geopolymer Hollow Block—Mix Design, Casting and Strength Comparison with OPC Hollow Block

Cement masonry units are not considered as sustainable due to consumption of fuel, cement and natural resources and embracing alternatives is mandatory. Geopolymer is a green cementitious material and has excellent mechanical properties, consumes low energy in production and emits less carbon dioxide. The effects of paste volume, proportion of alkaline activator and water/solid ratio were investigated to develop self-standing dry mix of geopolymer hollow block and compared with OPC mix. Factors that require attention in casting geopolymer dry mix are discussed in this article. The optimized mix of geopolymer self-standing dry mix is expected to be found between 30 and 35% of geopolymer paste volume for 7.5% of alkaline dosage and alkaline molar ratio of 1.00.

U. Johnson Alengaram, Iftekhair Ibnul Bashar, Marios Soutsos, Karthick Srinivas, Daniel Kong, Arreshvhina Narayanan, Ooi Jieun Lin, P. S. Khoo, Abhey Gupta, William Doherty

Analyzing the Moisture Susceptibility of Crumb Rubber Warm Mix Asphalt Using Imaging Technique

Damage-contributing factor of road pavement has become a concern in most of the previous studies. In some studies, it was stated that the weather and climate where the presence of water or moisture is one of the biggest factors. Thus, moisture-induced damage has been a major concern, associated with warm mix asphalt. This study analyses the moisture susceptibility of crumb rubber warm mix asphalt for both loose and compacted mixtures using imaging technique. Crumb rubber was added as dry mixtures at various crumb rubber contents and three different temperatures. Hydrated lime was added at 0 and 2%. Investigation of moisture susceptibility was performed through a series of the experiment such as Texas Boiling Test, Modified Lottman Indirect Tension adopted with Resilient Modulus analysis and Scanning Electron Microscope. The results were analysed qualitatively by using ArcGIS and through visual inspection. Quantitative analysis was performed by using MATLAB software to indicates the stripping percentage and Resilient Modulus value used to indicates the sample stiffness. From the results, inclusion of hydrated lime improved the moisture resistant. The presence of anti-stripping agent showed significant improvement asphalt mixture as most of the aggregates remain coated due to its property that improves the adhesion. The crumb rubber inclusion had a slight adverse effect as the total surface area interact with the bitumen is lesser compared to aggregate when interacting with the asphalt binder. Predominantly, stripping occured in wet samples, which eventually reduced the resilient modulus value can be further improved by incorporating the anti-stripping agent.

Lillian Gungat, Nurul Ariqah Ispal

Rainfall Trend Analysis in the Upper Citarum River Basin, Indonesia

Changes in rainfall pattern due to climate change have an impact on streamflow. Extreme rainfall has triggered an annual increase in flooding in the Upper Citarum River Basin. The present study, 18 years (1998–2016) of daily rainfall data at sixteen rain gauge stations was used to identify trends of the annual rainfall, annual maximum 24-h precipitation, and number of a rainy day at the Upper Citarum river basin, Indonesia. The non-parametric statistical test by Mann-Kendall (MK) test and the Sen’s slope estimator were applied to assess the trend of data and the magnitude of the slope. According to the MK test (S value) that approximately 75% of all station tend to increase for rainfall data. Meanwhile, related to Z value at a 95% confidence level, the trend of annual rainfall was increasing significantly in Cipeusing and Cipaku/Paseh stations, while Cisondari station shows a decreasing trend. 50% of the selected stations show a significant trend of the maximum daily rainfall, five stations namely Cicalengka, Cileunca, Rancaekek, Cipeusing, and Cipaku/Paseh stations tend to rise, while Cisondari and Lembang Meteo stations were reduced. Furthermore, Cipaku/Paseh station shows a significant upward trend for number of rainy day, in contrast with 15 stations, which indicate no significant trend of data.

Enung, Iwan K. Hadihardaja, M. Syahril Badri Kusuma, Hadi Kardhana

The Effect of Short-Term Exposure to Natural Outdoor Environment on the Strength of Tempered Glass Panel

Glass that used for architectural and structural purpose will undergo long term exposure to the natural outdoor environment. Exposure to outdoor weather such as temperature, humidity, UV-radiation, pH, etc. may cause deterioration of glass strength. This paper aims to study the effect of short-term exposures to natural outdoor environment on the strength of glass panel. Four sets of tempered glass samples were prepared for direct exposure to the outdoor environment. The samples were exposed to the outdoor environment for 40-, 80- and 120-days. A total of two tests namely microscopic observation on glass surface and four-point bending test on glass panel were conducted. Based on microscopic observation, the intensity of surface defects such as surface scratches, bubbles, and dust were increased for longer period of outdoor exposure. The bending and residual strengths of the glass panel reduced as the duration of the outdoor exposure was increased. The tempered glass material tends to undergo deterioration in strength by weathering process.

Mustafasanie M. Yussof, Shau Hui Lim, Mohd Khairul Kamarudin

Thermal Conductivity of Crumb Rubber as Partial Sand Replacement and Recycled Aggregates as Partial Coarse Aggregate Replacement in Concrete

Disposal of waste tire rubber has become a major environmental issue worldwide and is increasing day by day, especially in Malaysia where carbon emission is among the highest in the world. Therefore, recycled waste materials are being used as construction materials in order to create new innovative products that are able to mitigate environmental pollution, reduce the cost of construction and improve the properties of concrete. This study discusses the utilisation of crumb rubber and recycled aggregates in concrete construction and the objective of this study is to determine the thermal conductivity of crumb rubber and compare the optimum strength of concrete materials. 12 cube samples measuring 200 × 200 × 100 mm containing different percentages of crumb rubber (0, 1, 2, 3, 4, and 5%) as fine aggregate substitute and 50% of recycled aggregates as coarse aggregate substitute were produced. The concrete grade used for these specimens is grade 35. The curing process was conducted on the samples to achieve the standard strength of concrete in 7 and 28 days. Therefore, the real strength of concrete was measured after the curing process. A slump test was conducted to determine the properties of crumb rubber. In addition, the samples were examined using the guarded hot box method to obtain the optimum percentage of crumb rubber as partial sand replacement in concrete for thermal conductivity. The results show that thermal conductivity (k-value) decreased slightly with the increase in crumb rubber content. However, the quality of concrete also slightly increased as the percentage of crumb rubber content increased. Lastly, based on the results, 5% of crumb rubber and 50% of recycled aggregates were suggested as the optimum percentages to be used in concrete as it achieved the lowest thermal conductivity compared to conventional concrete.

Ridhuan Ramlan, Shahiron Shahidan, Nor Najihah Zainol, Sharifah Salwa Mohd Zuki, Alif Syazani Leman, Sajjad Ali Mangi, Ma Chau Khun, Fadzli Mohamed Nazri

Oxidation of Deep Well Saline Groundwater Generates the Precipitation of Ferrous Sulfide (FeS)

Hydrogen sulfide (H2S) gas can be traced once the groundwater is pumped out from a deep well which is located <10 km from the costal line. The groundwater contains 5.1 ± 0.1 ppt of salinity which is classified as saline groundwater. The initial color of the groundwater is green yellowish. After 40 s exposed to the oxygen, its colour suddenly turned to black and become sludgy. Afterwards, the black colour turns to partially cloudy after 8 h being exposed to the oxygen, subsequently, the H2S gas vanishes along with the disappearance of the black colour. Hence, from this reaction, this study aims to investigate the cause of the black precipitate formation which comes from the oxidation of the deep well saline groundwater. Based on the XRD and DSC results, the black precipitate is a troilite mineral (FeS). The elements that contained in the groundwater mostly originated from the seawater. The fast precipitation is caused by the Cl− content which is increasing the oxidation rate. The increase of Fe2+ is caused by the weathering process during the travel of the groundwater through the aquifer. Meanwhile, $$ {\text{SO}}_{4}^{2 - } $$ is decomposed by microorganism to produce S2− and this causes the reaction of Fe2+ and S2− to form FeS despite in saline condition.

M. F. Mohd Akhir, N. A. Saad, Nor Azazi Zakaria

Recycled Aggregate Concrete in Post Disaster Economic Construction

This paper aims at finding economic methods to reconstruct the destroyed cities post disasters and reduce the cost of reconstruction material in Iraq. One of these methods is to use of recycled fine aggregate (RFA) or fine recycled aggregate (FRA) instead of natural fine aggregate (NFA). Recycled aggregate concrete is resulting from many of the buildings destroyed as a result of natural or man-made disasters. The method of this research includes two parts, the first part includes theoretical aspect where data on RFA was collected, especially on the physical and mechanical properties, also on the information about cost of building material in Iraq, and the information about types and cost of stone crusher. Selected the best concrete mix containing RFA, that its physical and mechanical properties are better or closer to normal mix properties. The second part of the research is to conduct the practical side using the building information modeling (BIM) technique. A small destroyed city was modeled and it included various models of buildings. The amount of concrete used in ceiling and beams construction was calculated, extracting the volume of fine aggregate and its cost in the case of normal construction, and calculation of cost in the case of the use RFA instead of NFA, which is processed at the work site by a stone crusher can reduce the cost of building materials. The conclusions from this study is the total cost required for the purchase of building materials that used for the construction of ceilings and beams can be reduced by 18.38%.

Hafeth I. Naji, Mohammed Sh. Mahmood, Zahraa A. Jalil

Variations of Selected Criteria Air Pollutants During High Particulate Event

Nitrogen Dioxide (NO2), Ground Level Ozone (O3), and Particulate Matter with size less than 10 μ (PM10) are air pollutants measured under the Malaysia Ambient Air Quality Guideline requirements. The focus of this research is the interaction between each criteria pollutant as well as the effects of daytime (DT), nighttime (NT), four monsoon seasons [northeast monsoon (NE), southwest monsoon (SW), 1st intermonsoon (AM) and 2nd intermonsoon (SO)] and high particulate events (HPEs) that occurred in one year towards O3 concentrations. The hourly concentration trends of air pollutants were compared and contrasted using descriptive analysis and graphical analysis. Pearson correlation coefficient was used to analyze the relationship between PM10 with O3 and O3 with NO2. The results show that seasonal variation has the least effect for each pollutant. Even the correlation on each pollutant is less significant, the effect to monthly mean value indicates that HPE has the highest mean value of PM10 concentration at 116.16 µg/m3. April–May inter-monsoon has the lowest level of all three air quality parameters with PM10 (24.09 μg/m3), O3 (5.35 and 8.83 ppb) and NO2 (6.61 and 7.93 ppb), respectively. September–October inter-monsoon has higher mean concentration than April–May (PM10, 53.20 μg/m3; O3, 22.33 ppb and NO2, 8.29 ppb). DT and NT provide the information whereby O3 and NO2 are highly dependent on the daily human activities and sunlight as these two pollutants are significantly differenced between DT and NT. Besides, the study also showed that the mean concentration of PM10 in Taiping monitoring station has a positive correlation coefficient towards O3, which indicate that the increase of PM10 will increase O3. Essentially, during HPE, a high concentration of PM10 induced high formation of O3 compared to during non-HPE.

Syabiha Shith, Leong Weng Woh, Nor Azam Ramli, Maisarah Sulaiman, Nur Baitul Izati Rasli, Nurul Adyani Ghazali

Modal and Harmonic Response Analyses of the Kenyir Dam Intake Section

Modal and harmonic responses are the important analyses that need to be carried out to determine the behavior of a structure by executing data in a real-time. Through these analyses, several parameters of the structure can be identified. These parameters which are natural frequencies, mode shapes and frequency response function (FRF) are critical for monitoring and investigating of the dynamic behavior as well as to avoid unnecessary resonance to the structure. In this paper, the intake section of Kenyir Hydropower Dam in Terengganu, Malaysia is taken into consideration for the modal and harmonic response analyses. Numerical study using ANSYS software is performed for the real scale size of the intake section with a proper boundary condition. Six most significant result are selected from the modal analysis including the FRF for all three axes of the intake section. From the FRFs, the highest natural frequency value occurred at 11.024 Hz with the maximum deflection of 2.3203 m in the y-direction direction. This value must be taken into consideration for any external induced vibration to avoid the failure of the dam structure.

Azizi Arbain, Ahmad Zhafran Ahmad Mazlan, Mohd Hafiz Zawawi, Mohd Rashid Mohd Radzi

Identifying the Crack Nature Using b-Value Acoustic Emission Signal Analysis

Concrete is an important constituent of structures. The strength performance of the concrete decrease due to several factors. Concrete suffers from deterioration at a later stage. Early and constant identification of concrete deterioration is necessary. Nowadays, non-destructive testing (NDT) is widely used especially on continuous real-time monitoring system with minimum labor involvement. It could also be used to discriminate the different types of damage occurring in reinforced concrete (RC) beam and real structure. In this research was monitored by using Acoustic Emission testing and it have several analysis such as RA-value, b-value, intensity signal analysis and historical index. To determine the acoustic emission signals for concrete structures and cracking identification this research using b-value analysis. b-value signals analysis contain useful information about damage mechanisms. A high b-value arises due to a large number of small AE hits, it representing new crack formation and slow crack growth, whereas a low b-value indicates faster or unstable crack growth accompanied by relatively high amplitude AE in large number. Reinforced concrete beams measuring of size 150 mm × 250 mm × 1500 mm were used during the acoustic emission test. A four-point load test was carried out on specimens until cracking occurred. The signals generated from the equipment were used for the analysis process, and the values are compared to define and summarise type of cracking and cracking processes.

N. A. A. S. Bahari, Shahiron Shahidan, M. F. M. Shukri, Sharifah Salwa Mohd Zuki, M. Y. Norbazlan, M. H. W. Ibrahim, Fadzli Mohamed Nazri

The Effects of Mixing Speed and Reaction Time on the Removal of Colour and Turbidity from Alor Pongsu Landfill Using Tin Tetrachloride

The release of landfill leachate to the environment without appropriate treatment creates problems to the surroundings as it might affect the groundwater and surface water sources. The use of divalent and trivalent coagulants, for example, alum and ferric chloride are common in the coagulation and flocculation process of leachate. Still, the application of tetravalent chemicals is relatively scarce. In this study, experiments were carried out to assess the use of tin tetrachloride (SnCl4) as a potential coagulant in removing the colour and turbidity from the leachate taken from Alor Pongsu landfill site, Kerian, Perak. The effects of mixing speed and reaction time for various coagulant dosages and pH ranges were evaluated using a standard jar test. It was found that 99.5% of turbidity and 98.3% of colour were removed at 1 g/L dosage and an agitation speed of 220 rpm. Also, the mixing time of 3 min was chosen as the best agitation time as removal of 99.3% of turbidity and 98.2% of colour were achieved for the same dosage. The study inferred that the agitation speed and time are two important factors among the different mixing conditions that need to be determined in optimizing the coagulation/flocculation process.

Siti Fatihah Ramli, Hamidi Abdul Aziz

Modification of Malaysia Bituminous Binder Using Waste Polystyrene

Waste Polystyrene is a principal component of urban litter and marine debris. Proper management of waste as become a major concern. Waste Polystyrene is non-degradable and environmentally unfriendly. This study explores the economical use of waste polystyrene as polymer modifier in bitumen. Modified bitumen were prepared by adding 1, 2, 3% waste polystyrene in Malaysia bituminous grades (60/70 and 80/100). The characteristic properties and storage stability of the modified bitumen was evaluated and compared with conventional bitumen and results show a significant increase of 35 and 29% softening point values for 60/70 and 80/100 gradation respectively. There is a 20% reduction in the penetration values for both 60/70 and 80/100 gradation which is an improvement in characteristics of the modified bitumen and there is no significant change in the phase of the modified bitumen after storage. The utilization of waste polystyrene will not only improve bitumen performance but also create a friendly and sustainable environment by creating alternative reuse of the waste.

Olufemi A. Johnson, Ibrahim Kamaruddin, Ibrisam Akbar

HEC-RAS One-Dimensional Hydrodynamic Modelling for Recent Major Flood Events in Pahang River

The occurrence of severe floods in recent years globally as well as in many parts of Malaysia is an indication of both climate change and human interference in land use change. This requires for an integrated flood risk management approach and a shift from conventional structural flood mitigation. Flood modelling is an important part of flood risk management. In this study, development of one dimensional (1D) hydrodynamic model for Pahang River was performed in HEC-RAS 5.0 using combinations of surveyed data with spatial-extracted cross sections and recorded stream flow. The study area had been hit by several extreme floods that caused substantial property damages and loss of lives. This study focusses on the recent 2007 and 2014 flood events. Analyses of water levels, stream discharges and river cross sections were carried out based on the data gathered. A set of flood levels were obtained as the outputs of the hydraulic model and the accuracy of the simulated flood levels were validated. It was found that the model predicts a good output agreement with $$R^{2}$$ = 0.96 and $$R^{2}$$ = 0.82 for the 2007 and 2014 flood events respectively.

Muhammad Kashfy Zainalfikry, Aminuddin Ab Ghani, Nor Azazi Zakaria, Ngai Weng Chan

Flow Resistance in Ecological Subdrainage Channel

Ecological subdrainage channel is one of the components in a sustainable urban drainage system whereby stormwater is allowed to infiltrate grass channel drain into the subsurface drainage flow. This simple process results in significant reduction on runoff quantity while at the same time promotes better runoff quality, both of which are beneficial for flood and water quality control in urban catchments. A laboratory procedure to determine flow resistance of a newly designed REDAC module as subdrainage modular channel is presented by installing REDAC Module inside a 20-m rectangular flume. The result shows that the Manning’s $$n$$ of the modular channel is in the range of 0.018–0.036 demonstrating that the modular channel behaves hydraulically similar as a grass channel ($$n$$ = 0.030) in a free flow condition. Further result also shows that the modular channel enables flow attenuation induced by pressure losses at the entrance and exit of the modular channel. The head losses can be observed from the water surface profile presented in this paper.

Muhammad Kashfy Zainalfikry, Aminuddin Ab Ghani, Nor Azazi Zakaria, Ngai Weng Chan

Investigation on Strength Enhancement of U-TPOFA Based Binary Blended Alkali Activated Mortar Through Addition of Fly Ash

Alkaline activated binders (AAB), which are the results of reaction between source aluminosilicates and alkaline activator, are an environmentally friendly binder that exhibits high compressive strength (CS). This study explores the effects of different combinations of ultrafine treated palm oil fuel ash (u-TPOFA) and fly ash (FA) on the compressive strength and structural composition changes of the u-TPOFA-FA alkali-activated binary binder mortar (AABBM). The alkaline activated mortar (AAM) was synthesized using mixtures of u-TPOFA and FA in varying ratio of u-TPOFA:FA of (100:0), (90:10), (80:20), (70:30), (50:50), (25,75) and (0:100), respectively, and the alkaline activating solution consist of a combination of Na2SiO3 and NaOH. The combination and concentration of Na2SiO3 and NaOH were constant for all mixtures. Primarily, it was found that mixture with a combination of u-TPOFA:FA of 25:75 gain the highest compressive strength (CS) of 54.82 MPa at 28 days. Therefore, the replacement of SiO2 from u-TPOFA by Al2O3 provided by FA contributes towards significant CS enhancement due to the formation of more N-A-S-H gel binder. The result observed for the gel binder formation was emphasized with XRD and FTIR analyses.

Otman M. M. Elbasir, Megat Azmi Megat Johari, M. J. A. Mijarsh, Zainal Arifin Ahmad

Human Factors Lead to Lift Accidents in High-Rise Residential Buildings

Lifts widely used as vertical transportation in high-rise buildings. Lift accident cases are increasing every year, giving a negative impact to building occupants in terms of their confidence in using lift system. To uncover the key lift accident factors, this paper identifies various human factors of lift system accident in buildings. This study used frequency analysis by extracting lift accident factors from 25 research articles and a total of 20 factors was found. The key factors identified based on matrix table were; fail to allocate sufficient maintenance budget (f = 10), poor maintenance workmanship due to lack of skills (f = 6), refuse to pay maintenance fees (f = 6), vandalism (f = 6), poor maintenance workmanship due to lack of knowledge (f = 6) and replace components with low-quality spare parts during maintenance (f = 6). Through identifying the key factors, the lift accidents can be avoided. This will benefit building maintenance managers, lift technicians and building occupants towards effective preventive maintenance, reliability and safety of the lift system.

Mustazha H. A. Tahari, Zainal A. Akasah, Sasitharan Nagapan

Integrating Structural and Non-structural Flood Management Measures for Greater Effectiveness in Flood Loss Reduction in the Kelantan River Basin, Malaysia

The state of Kelantan in Malaysia is a flood-prone state exposed to seasonal Monsoon rains that bring seasonal floods resulting in significantly losses. Flood management in the state is modelled after the country’s predominant government-centric top-down approach focused on flood-control technologies via structural measures such as multi-purpose dams, levees, embankments, tidal gates, diversion channels and others. These structural measures do not engage the public who fail to understand the measures leading to lack of confidence, misunderstanding and mistrust. This results in ineffectiveness of the measures leading to greater flood losses. In contrast, local communities are familiar with non-structural measures which they have long used to adapt to floods. These measures are also relatively simple, cost-effective and easily implementable over a short period of time. Both measures, however, must engage the public/victims in all phases of the flood disaster cycle. Balancing both types of flood management measures is the key to more effective management. A combination of structural and non-structural measures is the way forward for Kelantan State as it ensures that government structural measures are effectively supported by public-engaged non-structural measures.

Ngai Weng Chan, Aminuddin Ab Ghani, Narimah Samat, Nik Norma Nik Hasan, Mou Leong Tan

Flood Risk Estimation of Paddy Production Considering Plants’ Age and Flood Durations

Floods pose serious threats worldwide. During this disaster, civil engineering structures, such as buildings, bridges, dams, water supply, coastal structures, infrastructure facilities are severely affected, causing immense inconvenience to people and disrupting routine life. In the context of water-food security, floods have been a major source of natural disturbance to rice productivity in Malaysia. The consequences of floods will bring losses to the rice production and cause instability. The damage of paddy production due to floods needs to be handled seriously as the negative impact could lead to insufficient food supplies in the country. The purpose of this paper is to estimate flood risk in paddy production considering different flood inundation durations and plant’s ages. The calculation of risk considers the probability of extreme flood levels and fine cell resolution of paddy field in the total loss estimation. The location used for this study is in Kedah, where rice production is among the most prominent in Malaysia. Flood risk is expected mounting to nearly half a million ringgits for the 330 ha plots considering the current condition. This emphasize on an effective long-term flood risk management in order to reduce flood risk to paddy production.

Balqis M. Rehan, Ainun M. Yusuf, Iffah L. Idham

Morphological Identification of Latex Modified Asphalt Binder Prepared with Surfactants

The microscopic spreadability and storage stability of conventional asphalt binder (PEN 60/70) and 6% natural rubber latex (NRL) modified asphalt binder (with and without the incorporation of surfactant) were investigated in this study. The prepared samples were assessed under both unaged and short-term ageing (RTFO-aged) conditions. Subsequently, the storage stability was conducted on all asphalt binder samples under conditioning condition designated at 180 °C for 72 h. Optical and polarising microscopes were used to observe the surface morphology of asphalt binders. The results revealed that for 6% NRL modified asphalt binder under unaged condition, the formation of globular agglomerated microstructures can be detected. However, the NRL modified asphalt binder that is subjected to RTFO-ageing with the incorporation of different additives yielded homogeneous and interconnected structures with lamellar orientation. This is due to the evaporation and absorption effects, which could have improved the rutting and fatigue resistance of asphalt binders. The storage stability results exhibited similar microstructures with little or no observable morphological differences. Overall, the incorporation of surfactants improved the miscibility, homogeneity, and stability of latex modified asphalt binder.

Ashiru Sani, Mohd Rosli Mohd Hasan, Khairul Anuar Shariff, Sharvin Poovaneshvaran, Ilham Ibrahim

Alternative Testing Protocol to Assess the Bonding and Shear Resistance of Pavement Bituminous Crack-Sealant Material

Conventional asphalt binder is widely used as the crack sealing material. Crack sealing is one of the most frequent pavement maintenance methods. The level of performance during service life has a close relationship with the properties of asphalt binder used in the pavement or as crack sealant material. As for the pavement crack mechanism, there are two different working mechanisms that occur within the pavement crack, which is horizontal and vertical movement. Horizontal movements are caused by shrinkage and expansion of pavement due to the thermal changes in pavement material. While, the moisture related changes causes vertical movement. This study aims to introduce an alternative testing protocol that can simulate the real failure mechanism of pavement crack. This is due to limited approaches that had been taken by previous researchers to evaluate the performance of pavement-crack sealant. The tensile strength and resistance to shear stress had been chosen as the main performance evaluations in pavement crack sealant material. Prior to that, the bond test and Layer Parallel Direct Shear Test had been used to evaluate the tensile strength and shear resistance of crack sealant material, respectively. This testing protocols could be adopted by other researchers for further studies and also by the asphalt industry.

Sharvin Poovaneshvaran, Mohd Rosli Mohd Hasan, Ashiru Sani, Raa Khimi Shuib

Behaviour of Ultra-High-Performance Concrete Barrier Walls Subjected to Blast Loading

In this study, a numerical simulation is conducted using AUTODYN-3D where two concrete barrier walls are exposed to blast loads. To investigate the effect of using ultra high-performance concrete in mitigating the effect of blast waves, two numerical models were carried out. The reflected over pressure and post-test damage were analyzed. The results have shown that UHPC barrier walls performed a lot better than NSC barrier walls in blast loading resistance.

Ahmed K. Taha, Zhengguo Gao, Dahai Huang, M. S. Zahran

Simulation of Flow Profile Response to Alternate Bar Formation in Rivers

Alternate bars are common in alluvial rivers. The formation of alternate bars is derived from the instability of flow and sediment in the channel. The formation of the alternate bars causes the changes in hydrodynamics condition in the channel. This study presents the analysis on the impact of alternate bar formation on the characteristic of flow in the channel. The objective of the study is to investigate the effect of alternate bars on the flow distribution. The study was observed through 2D computer simulation analysis by using Nays2DH solver in iRIC software. The length and width of the channel used were 12 and 0.5 m, respectively. The channel bed was initially set to be flat. The discharge was kept constant with different sediment sizes. The study found that the direction of the velocity of water was diverted away from the alternate bars after these bars were formed. Furthermore, the variation of sediment size does not majorly affect the conditions of the alternate bar; thus not also affected the flow profile. However, the velocity was progressively increased from upstream to downstream in the channel with a bigger size of bed material. Additionally, the velocity also was higher at the center but lowered on both sides of the channel. The profiles of velocity were mainly parallel with the bed level, where the velocity was higher as the bed level increased.

Mohd Zulkhairi Mat Salleh, Zulkiflee Ibrahim, Mazlin Jumain, Radzuan Saari, Muhammad Farid Muhammad Fathullah, Zulhilmi Ismail, Muhammad Hidayat Jamal

A State-of-the-Art of the Emergency Evacuation Capacity (EEC) Assessment for Rail Transit Terminal (RTT) in Malaysia

Railway system has evolved as one of the important modes of public transport and a favorite alternative method in resolving traffic congestion problem especially in urban areas like Kuala Lumpur, Malaysia. It is reported that rail passenger volume is increasing yearly which caused more attention are made to the safety and emergency evacuation plan, especially if unexpected accident or emergency occurs in Rail Transit Terminal (RTT). The failure of emergency evacuation in any public buildings such as RTT may lead to a large scale of injuries or death. Despite the fact that a lot of safety measures and emergency response plans are taken as an initial preparation to face any emergencies that may occur in RTT, the emergency evacuation capacity (EEC) assessment studies are necessary to assess the effectiveness of the system implementation. Before employing any methods of assessment, it is crucial to scrutinize the factors that affect the effectiveness of EEC for any rail transit terminal. To the best of our knowledge, there are limited studies conducted on the EEC assessment at RTT in Malaysia. By virtue of this, we expect this paper provides a comprehensive review of a state-of-the-art of the emergency evacuation capacity (EEC) assessment for rail transit terminal in Malaysia by focusing on two important elements: (1) factors affected the effectiveness of evacuation capacity; and (2) methods of evacuation capacity assessment.

Norley Nadirah Shaari, Noorhazlinda Abd Rahman

Characteristic Study on Malaysia Power Plant Fly Ash Cenosphere

This paper investigates the characteristic of cenosphere derived from fly ash collected from Malaysia power plant. The current trends on the reuse on cenosphere has been reviewed and various characteristic properties of cenosphere were presented and compared with cenosphere from Malaysia power plant. Fly ash was collected from Jimah, Manjung and Kapar power plant and was processed to extract the cenosphere. Cenosphere was undergo chemical composition test, particle size distribution identification, surface morphology and crystallographic structure in order to study the characteristic. Cenosphere were found to have smooth surface and a spherical morphology with high amount of silicon dioxide and aluminum oxide. Cenospheres will give a huge effect potential due to the unique properties, where it will be amenable to a wide range of industrial applications used in the engineering industry, highway engineering, oil and gas industry, foundry engineering as well as the chemical industry.

Salmia Beddu, Mahyun Mohd Zainoodin, Zakaria Che Muda, Daud Mohamad, Fadzli Mohamed Nazri, Zarina Itam, Siti Nabihah Sadon

Investigation of Natural Fibers as Ceiling Material

This paper investigates the performance of scirpus grossus (SG) fiber and fiberglass (FG) as ceiling material. Scirpus grossus was extracted by peel method. Mixture containing scripus grossus, fiberglass and carboxymethyl cellulose (CMC) was cast with thickness of 7.5 and 15 mm of both fibers namely as 7.5SG, 15SG, 7.5FG and 15FG and undergo tensile strength test, flexural strength test and water absorption test. The result show, 7.5FG has the highest water absorption compared to SG7.5 with difference of 21% whilst for ceiling with thickness of 15 mm, 15SG show the lowest value of water absorption compared to 15FG with 17% of difference. Meanwhile, flexural strength of both thicknesses was comparable for both fibers. It is concluded that, natural fiber shows a good potential to be explore as ceiling material for energy efficiency building application in future for tropical climates zones area.

Salmia Beddu, Mahyun Mohd Zainoodin, Zakaria Che Muda, Nur Liyana Mohd Kamal, Daud Mohamad, Fadzli Mohamed Nazri, Sivakumar Naganathan, Nadiah Md Husain, Siti Nabihah Sadon

Experimental on the Damages of the Cable-Net Structure Under Static Performance

Structural glass facades or cable-net supported glass façade has been widely used as a modern building facade in engineering construction for a long-span greater than 7 m because of their simple, light and transparent appearance of the structure. With these advantages make them dominant in various applications especially for the building that emphasize the high aesthetic value in term of appearance and also a large space such as airport, hotel and many more. In this research, the damages of cable-net structure were investigated for both with and without glass panels under static behaviour. Three type of damages were considered in this research which are failure of cable connector between two intersection of steel wire cables, different percentage of cable pre-stress losses which are 30 and 60% loss and lastly is cable end anchorage failure with the 100% loss of cable pre-stress force. The deflection of the cable-net with and without glass panels is used to determine the contribution of glass stiffness to the cable-net structure. The cable connector failure shows a little effect rather than the cable failure which are cable pre-stress losses and cable end anchorage failure to the performance of the cable-net structure.

N. Ashikin Marzuki, M. M. Yussof, M. S. Azhar, Kok Keong Choong, H. M. Yee

Road Traffic Noise Assessment at Sekolah Kebangsaan Sungai Bakap, Sungai Bakap, Penang, Malaysia

This study is intended on the assessment of traffic noise at Sekolah Kebangsaan Sungai Bakap where this study area located near the main road (Jalan Sungai Bakap). The objectives of this study are to determine noise levels during school hours, to identify the source of noise and to establish the noise profiling in the Sekolah Kebangsaan Sungai Bakap environment. With using sound level meter instrument, the noise levels at school were measured where 19 points were selected at school area in order to collect the value of all parameters measured in this study (Leq, Lmax, Lmin, L10, L50, and L90). Each of the noise measurements was taken for 3 minutes in duration and the time taken for all measurements conducted from 8.30 a.m. to 12.00 p.m. Noise mapping performed using ArcMap and My maps website based on the latitude, longitude and also noise parameters. Manually traffic count was conducted to count the number of vehicles on the road. Traffic composition data in this study was categorized into four types, which passenger car and van, motorcycle, medium lorries and heavy lorries. The result showed that the measured noise levels at school area in term of Leq were between the range of 54.8–72.9 dB(A), where it was found that the highest noise level generated was at road zones. From this study, all noise data collected exceeded the Malaysian noise limit. Apart from that, based on the noise mapping it showed that highest noise levels were located in traffic zones area.

N. A. M. Saip, H. Halim, A. H. Salleh, A. Z. Amiruddin, Z. Ibrahim

Prediction of Odour Pollution in River Water Contaminated with Landfill Leachate Using COD and UV Absorption Indices

The quality of the source of drinking water is very important for human being. One of the parameter that is yet to be established in Malaysia is odour in the drinking water source. According to Ministry of Health Malaysia, the only acceptable limit mentioned in the drinking water standard is “no odour”. The objective of this paper is to find the correlation between odour and the other two parameters which are Chemical Oxygen Demand (COD) and organic matter. From this research the result shows that, Threshold Odour Number (TON) and COD have a strong correlation determined using Pearson’s Correlation, while the regression curve shows that, TON and COD best fit curve is cubic. Cubic model has the highest R2 value compared to the others curve. Same goes to natural organic matter, ultraviolet absorption at 254 nm wavelength (UV254) versus TON is best fitted with cubic graph and has the highest R2 value. Both of the equation acquired from the graphs can be used to predict TON value if the sample has the same condition as the one used in this study.

Syafinah Yusoff, Nastaein Qamaruz Zaman, Ahmad Shukri Yahya, Nurul Hana Mokhtar Kamal

Comparison of Different Methodologies for Determining the Efficiency of Gully Inlets

This paper describes the different methodologies used to determine hydraulic efficiency of gully inlets based on an experimental investigation of a site located at the exit toll of Bandar Baharu Highway, Malaysia. The inlet efficiency was determined using selected methodologies proposed by other studies to determine the difference (% variance) between each method. Data was obtained from an experimental set-up with a 1:1 scale (with single carriageway) laboratory system consisting testing platform, gully system (grating, gully box) and inlet and outlet tanks. The set up was designed to mimic the real condition of the gully system on site. There are numerous methods proposed by other studies to determine the inlet efficiency, however only three methods were selected for this study. The selected methods are general equation—method 1, British Standard (BS EN 752) and DMRB (CD 526)—method 2 and UPC methodology—method 3. The experimental results showed that the percentage of difference found between these methodologies was between 2 and 7%. The aim of this paper is to outline some of the available methods to date, to establish inlet efficiency and hence advocate the use of the recently developed methods/equations in Malaysia.

Sarah Alia Md. Wakif, Nuridah Sabtu

Utilization of Polyaluminium Chloride (PAC) and Tapioca Peel Powder (TPP) in Coagulation of Leachate for Degradation of Suspended Solids, Color, and Chemical Oxygen Demand

Treatment of leachate requires highly chemical treatment method that may contribute hazard to environment. Hence, a verdant composite coagulant is utilized as an alternative to excessive usage of inorganic coagulant in treatment of leachate. The new composite coagulant (PACTPP) developed in this study is from polyaluminium chloride (PAC) and tapioca peel powder (TPP). The aim of this study is to evaluate the efficiency of different ratio of PACTPP in coagulation of leachate through degradation of suspended solids (SS), color, and chemical oxygen demand (COD) in Simpang Renggam landfill under the optimum leachate pH and dose of coagulant. The leachate can be categorized as old leachate. From this study, the result obtained for optimum ratio was 4(TPP): 7(PAC) and optimum dosage of 3000 mg/L with percentage removal for SS, colour, and COD was 70.0%, 86.1%, 65.34% respectively. Meanwhile the optimum pH of leachate sample was at pH 6, by removing 63.0% of SS, 76.26% of color, and 58.6% of COD. Thus, by the utilization of PACTPP, the discharge standard requirement were able to achieve except for colour parameter.

N. A. Ismail, M. Z. N. Shaylinda, S. N. A. Mohd-Salleh, W. M. W. Afnizan

Utilization of Sugarcane Pressmud as a Natural Absorbent for Heavy Metal Removal in Leachate Treatment

This study aims to assess the ability of pressmud as an absorbent for heavy metals removal in leachate treatment. Pressmud is an organic waste, produced from sugar manufacturing that contains high amount of water, calcium and silica. The existing compounds of pressmud have potential to become an absorbent for physical-chemical treatment process; especially for heavy metal removal. Heavy metals are in great concern as it has spread and frequently released into the environment. Heavy metals for example zinc, iron, arsenic, cadmium and lead were studied recently as the main component in landfills leachate. The absorbent study was conducted at shaking speed of 200 rpm, 24 h retention time at room temperature, constant pH and various pressmud dosage at 0.5, 1.0, 2.5, 5.0, 7.5, 10.0 and 20.0 g. The results indicated that the pressmud function to minimize the concentrations of heavy metals approximately 60% of Fe2+ (1.8 mg/L) followed by 92% of Mn2+ (0.01 mg/L), 76% of Pb2+ (0.03 mg/L), 61% of Zn2+ (0.86 mg/L), 58% of Cd2+ (0.004 mg/L) and 14% of Cr2+ (0.13 mg/L). It was found that the best optimum point of removal efficiency was obtained at 10.0 g of pressmud.

Nurul Nadiah Mohd. Azme, Mohamad Fared Murshed, Siti Aisyah Ishak, Mohd Azam Mohd. Adnan

Linking Science and Administration: Local Ozone Management and Prevention Framework in Malaysia

Ozone at ground level was proven to have causal relationships with ill health of human. Managing air pollution was carried out mainly as federal initiatives. Local ground ozone management has not been given adequate emphasis. There were studies conducted to path basic understanding of the ozone critical conversion point (CCP) which explain ozone transformation behaviour from its precursors. The interactions diurnally between nitrogen oxides, temperature and sunlight, have determined photochemical ozone rates. The obtained CCP lies in between the critical conversion time (CCT) which is from 8.00 to 11 a.m. as been determined using composite diurnal plot method which has open the possibility to use photochemical ozone rates to determine CCT. This crucial information could be further used to determine exact rates of ozone photochemical transformations from its precursor. Understanding the behaviour of ozone transformation should lead to local ozone management plan being drawn. The authorities could adopt the proposed framework of local ozone management and prevention in Malaysia for more effective actions.

Nor Azam Ramli, Syabiha Shith, Norrimi Rosaida Awang

Study on the Characteristic of Marine Dredged Sediment Using Admixture

Dredge material can be used depending on their characteristic; hence this study aims to determine the characteristic of dredge marine sediment using admixture. Physical and chemical characteristic of dredge marine sediment is carried using the dredge sample taken from Terminal Jetty Lumut, Perak. The samples are stabilized using ordinary Portland cement (OPC) and strength measurement test such as cube compression test were carried out. The physical characteristic was determined, and it is considered as well-graded sand. The X-Ray fluorescence (XRF) test is carried out to determine the chemical characteristic that contained in the sample it was found that there were a lot of chemical compound found in this sample such as silica, aluminium and also gold oxide found. The mixture of dredge marine sediment with OPC to produce pave walk did not give a good results, hence some recommendations are given to make sure perfect mixture of pave walk produced such as mixing lime and kaolin in this sample and using geotechnical strength testing such as unconfined compression test to determine the strength of this material.

Prakash Kumaravelu, Mastura Azmi, Siti Aimi Nadia Mohd Yusoff

Comparison of Bioavailable Phosphorus in River Sediments and River Bed Sediments from Agricultural and Urban Rivers

This study was carried out to determine the concentration of phosphorus in six rivers from agricultural and urban rivers and to compare the bioavailable phosphorus (BAP). Nutrients entering rivers are divided into suspended and dissolved state. In this study, BAP was measured by using ultrasonic extraction method. A 100 L sample was collected from six rivers, three agricultural rivers and three urban rivers to compare their BAP concentration. Measurement for two weather conditions, rain and no rain were taken. The results showed that BAP concentrations were high in Nishino river followed by Hamada, Umeda, Yagyu, Asakura and Uchibari river, with the concentration ranging from 0.1 to 1.00 mg/L. Agricultural rivers for both rain and no rain events were high in total phosphorus (TP) with the concentrations ranging from 0.50 to 1.09 mg/L. Particulate phosphorus (PP) concentration in the river sediment (RS) after a rain event was high compared to the PP during a no rain event. However, PP in river bed sediment (RBS) was high during a no rain event compared to the concentration of PP in the river sediment (RS). This may due to the accumulated and attached PP in the RBS (low flow of river water). Concentration of particulate bioavailable phosphorus (PBAP) in RS was ranging from 0.70 to 10.94 mg/g. In this study, it was found that the BAP concentration from agricultural rivers were high than the BAP concentration in urban rivers.

Nur Fatin Hanani Binti Mohd Halid, Takanobu Inoue, Kuriko Yokota, Makoto Saga

Supply Chain Framework in Enhancing Construction Waste Management: A Case Study in Klang Valley

Construction Waste Management is part of a growing movement towards a sustainable world. The Eleventh Malaysia Plan had played a significant role in the demands of executing major residential housing project developments where it has been observed that construction wastes was one of the priorities among waste streams. The lack in the highlighting of the proper flow of the construction waste process has called for a need to contextualize, explore and document its practice in the construction industry to identify the current existing process of construction waste management, the barriers and the major types and composition of construction waste generated. The aim of this research is to develop the supply chain framework. This aim was achieved through a preliminary study and a case study method which was conducted in the Klang Valley using the qualitative and quantitative methods. First, a semi-structured interview was conducted among 20 contractors (G7) to identify the current existing process for construction waste management. The second method distributed the questionnaires and 60 responses from contractors (G7), clients and consultants were received on the barriers in the construction waste management process. The Third method conducted a survey on the heaps of waste through observation, estimated to identify the main types of construction waste produced. The main conclusions drawn from the findings gathered have produced that the supply chain framework consists of five main stages or process: waste generation, waste collection, waste segregation, waste reusing and recycling; and waste disposal which is directly used in managing the major construction waste produced including wood, metal, steel, bricks, cement and packaging. Each of these processes consists of comprehensive action taken and specific barriers as strategic items in enhancing the managing process of construction waste. With that, the establishment of this supply chain framework could enhance the current existing process in managing construction waste whereby indirectly reducing the amount of construction waste from being directly disposed in landfills through reusing and the recycling process.

Raja Nor Husna Raja Mohd Noor, Intan Rohani Endut, Ahmad Ruslan Mohd Redzuan, Nurol Huda Dahalan, Juzailah Nur Yunus, Nor Janna Tammy

Empirical Study on Relationship Between Customer Satisfaction and QLASSIC Performance Score in Northern Area

There are many factors that may contribute to the successful of producing quality product for construction project in Malaysia and one of the factors is by using legitimate monitoring checklist as assessment. In Malaysia, Quality Assessment System in Construction (QLASSIC) had been implemented and most of the construction project had obtained highest percentage of QLASSIC performance score. This research is carried out to identify the relationship between customer satisfaction and QLASSIC performance score. The aim of this study is to collect data by using sets of questionnaires. The frequency analyses are carried out by using Statistical Package for Social Science (SPSS) software. The result shows that customers of the building with higher QLASSIC performance score is highly satisfied with their condition of the building and there is significant relationship between QLASSIC performance score with customer’s satisfaction especially in architecture aspects.

N. H. Dahalan, N. Tutur, R. H. R. M. Noor, J. N. Yunus, N. N. M. Yusoff

Geographic Information System for Flood Control: Cilember River, Cimahi City, West Java Province

Urban floods, such as those that occurred in Cimahi City in the last 10 years, have quite extensive economic impacts and are difficult to manage. To develop a comprehensive flood control plan, a complete, integrated and well-structured database is needed. This study will build a Geographic Information System (GIS) to control water damage by conducting flood simulations on the Cilember River in Cimahi using parameters such as hydrological data, river crossings, DEM data, and flood models that are processed using 2-Dimensional flood simulation HEC-RAS Software. The simulation was run based on 2 and 5 years return period of rainfall. The results are presented as a Geographic Information System for Flood Control that visualizes a flood map model, which can identify the location of floods, flood depth, area of flood. Validation of models shows that despite the differences in flood depth between simulation result (max depth 200 cm) and actual condition (max depth 100 cm), there is a suitability of the flood location between the model with the actual conditions. Simulation result also shows that by normalization and widening of the river, the flood conditions which initially had a depth of 10–200 cm, was reduced to 10–140 cm.

Yackob Astor, Iin Karnisah, Bambang Setio Budianto, H. Dandi Aprillian

The Criteria of Evaluating Active School Travel at Jerash Camp

Promoting active travel to school has become a growing interest for governments and organizations in the past decades. However, it is less known how children in the refugee camps travel to school. This paper aims to identify the possibility for the children at Palestinian refugee camps in Jordan (Jerash Camp) to involve with the Active School Travel. Jerash camp was selected as a representative case of the ten official camps in Jordan for Palestinian refugees because of it is among the oldest and compact refugee camps. The preliminary investigation found factors such as social and economic conditions on the safety and security of school children may contribute to the possibility of Active School Travel in the camp. However, the condition of pedestrian facilities and route conditions maybe become the deterrent factors. As a conclusion, the findings from the preliminary study can be used to plan a better design and improvement to promote the active school travel for children in Jerash camp.

Enas Al-Najjar, Nur Sabahiah Abdul Sukor, Lina I. Shbeeb

Building a Digital Model to Protect the City of Nasiriyah from Hydrological Hazards by Using Topographic Survey Methods and GIS

The Digital Elevation Model (DEM) is a representation of the topography of the Earth’s surface and terrain. There are many ways in which the digital elevation model can be obtained, such as the Field Survey and the use of Global Positioning System data, topographic maps and other methods. In this research, a Digital Elevation Model (DEM) has been built dependent on three methods (positioning system—ground survey—topographic maps) in addition to the use of GIS technology to produce high-resolution 3D maps (2 mm) was chosen for application to the city of Nasiriyah, the center of Dhi Qar governorate in the southern Iraq to show the Hydrological hazards on the studied area and the methods of protecting it. It was found that there are many hydrological hazards to the city especially in the winter season such as the erosion of the soil by rain which reached 12.977 tons/ha and the water immersion whose ratio reached to 0.34 cm in some areas. In addition, the study showed that the area is exposed to the danger of flooding in percentages ranging from 0 to 90%, covering 50–60% of the risk of most parts of the study area. Finally, it was concluded that the rise of groundwater levels (0.73 cm) affects on buildings, foundations, soil and infrastructure.

Heba Sahib Dakheel, Raheem Hameed Abed, Murtadha Sarhan Satchet

Development of Mode Choice Models for Undergraduate Students in Baghdad City

Mode choice is one of the most essential stages in the transportation planning process and it has a direct impact on policy-making decisions. Mode choice models deal very closely with the individual preferences and behavior, thus continues to attract researchers for further investigation of commuter’s choice making process. This study contains a review of various modeling methods of mode choice analysis, the factors that affect the personality of the travelers have been discussed also. Furthermore, it emphasizes on students who have some characteristics of tripmakers that differ from those of other tripmakers. These characteristics are related to their priorities like time importance and safety. In this study, the main purpose was to develop mode choice models for students in three universities in Baghdad city. A questionnaire was designed and distributed at the three universities under study, then behavioral mode-choice models were successfully built and validated. These models pointed that travel cost, gender, travel time, comfort, and safety have their effects on travel modes of utilization. These models will be helpful in travel demand analysis, so it can be considered by related authorities to improve public transit services in order to shift these users from private to public transport, thereby contributing to sustainability.

Hanan Adil Khudhair, Samer Muayad Alsadik

The Hydraulics and Morphodynamics of a Flooded Meandering Channel

Meander dynamics has been the focus of river engineering for decades; however, it remains a challenge for researchers to precisely visualise natural evolution processes especially in alluvial plains. The evolution of meandering channels is a complex geomorphological process driven by the interactions between flow and alluvial channel beds and banks. The presence of vegetation along a riparian zone added the complexity of geomorphological process. Riparian vegetation is a major roughness element that influences channel morphology, decreases the average flow velocity and physically traps material that transported in alluvial rivers. A laboratory experimental investigation was carried out in Universiti Teknologi Malaysia in order to understand the flow behaviour and morphodynamics for a riparian vegetated flooded meandering channel. The morphological patterns visualisation and river channel profile changes estimation for pre and post flooding were obtained using digital close range photogrammetry technique. The findings prevailed that riparian vegetation had induced higher resistance to the flow and forced the flow to take place in main channel and right flood-plain while reduced the left floodplain flow velocity. The presence of riparian vegetation combined with the river bed morphology had increased the Manning’s n in left flood-plain. The influence of riparian vegetation on the sediment movement in the compound meandering channel was also identified. The sedimentation was 45% increased, while erosion decreased about 31% as the floodplain was roughened by vegetation.

Zulkiflee Ibrahim, Radzuan Saari, Mazlin Jumain, Muhammad Nazmi Akmal Masri, Muhammad Afiq Md. Aris, Nur Atila Amzah, Md. Ridzuan Makhtar, Nurfarhain Mohamed Rusli, Abu Bakar Fadzil, Noraliani Alias, Amat Sairin Demun, Nor Suhaila Rahim

The Influence of Extensive Green Roofs on Roof Thermal Performance in Batu Pahat Climate

Climate change has increased global temperatures. When air temperature rises, it affects the condition of urban areas and creates discomfort among inhabitants of buildings. A potential sustainable approach to overcome the global warming issue is to implement green roof technology. This study aims to determine the effect of green roofs on roof thermal performance and to identify the best plant species which has the potential to lower temperatures. This study also determined the U-value, R-value, k-value and heat-flux parameters that constitute the thermal behaviour of green roofs. Three identical small-scale roof houses were constructed with one non-vegetated roof house as a control while the other two vegetated roof houses were planted with Portulaca G. and Alternanthera P., respectively. Surface roof temperatures were collected from both inside and outside the roof of each house. Results show that the average differences in temperature inside the building between the control roof and the green roof were 0.02 °C and 0.22 °C for Portulaca G. and Alternanthera P., respectively. Meanwhile, the average differences in temperature on the control roof and the green roof were 1.12 °C and 2.84 °C for Portulaca G. and Alternanthera P., respectively. The heat flux value of Alternanthera P. roof is 3.15 w/m2 better than Portulaca G. roof at 7.72 w/m2. This concludes that the roof with Alternanthera P. reduces heat that travels through the roof layer better than Portulaca G.

Mohd Norfekry Md. Yacob, Hartini Kasmin, Mohd. Khairul Adam Mohd. Kori, Wan Afnizan Wan Mohamed, Siti Nazahiyah Rahmat, Mohd. Shalahuddin Adnan

Evaluation of Cost Analyses for Earthquake Resistant Reinforced Concrete Buildings Based on Malaysian National Annex to Eurocode 8

Earthquake is one of the most destructive natural disasters. Malaysia is perceived as an earthquake-free zone because the country is situated relatively far from active seismic fault region. As such, almost all buildings in Malaysia were designed without considering and seismic action. However, the June 2015 Ranau earthquake has proven that buildings in East Malaysia can be susceptible to damage due to local earthquake event. With the establishment of Malaysia National Annex to Eurocode 8, buildings in Malaysia can be designed considering seismic loading. A number of studies have been conducted to investigate the response and the change in the material cost, however, the results were scattered. This study aims to investigate the increase in the material cost due to the adoption of seismic loading and evaluate the influence of building height with respect to the material cost. Three types of buildings with different storey height were generated in the designs namely, low rise (5-storey), medium rise (10-storey) and high-rise (20-storey). All models were regular in plan and elevation and generated into two-dimensional (2D) reinforced concrete moment resisting frame using SAP2000 software. The results showed that the cost for the main frame members increased 41%, 25% and 7% for low-rise, medium-rise and high-rise, respectively.

F. Faisal, S. S. Zaini, T. Selokumar

Co-composting of EFB and POME Using Rotary Drum Reactor by Partially Sequence Feeding Strategy

The objective of this study is to improve the co-composting method of empty fruit bunches (EFB) and palm oil mill effluent (POME) sludge by employing a mechanical rotary drum reactor. In the operation of this composting process, 4 feeds each with a mixture ratio of 20 kg EFB and 10 L sludge was added to the rotary drum reactor. The feeding strategy adopted in this composting process known as partially sequence feeding method. Parameter as pH, temperature, C/N ratios, moisture content, nutrient, and heavy metal elements plays as an indicator of the maturity level for the final compost product. From data collected, the pH profile was increased from 7.6 to 9.74 during the treatment process, but towards the end of the process, the pH profile starts to decrease until reached 7.59 which in the optimum and recommended pH value for the compost. The early C/N ratio is 22.73 was significantly reduced to 9.11 after 14 days of treatment process. The ultimate C/N ratio after 111 days of the composting process is 10.29. Optimum C/N ratio for composting is within 15–25 but with final C/N value below than 15 indicates the compost product are matured and ready to use for plantation. Additionally, very low levels of heavy metals (Ni, Pb, Cd and Cr) were observed in the compost product and all the elements are untraceable. The compost product might accommodate in palm plantation as fertilizer and soil modification.

Rosnani Alkarimiah, Fatihah Suja’

Numerical Investigation on the Effectiveness of a Novel Flat Truss Shape Punching Shear Reinforcement

This research aims to gain understanding of the effectiveness of a novel flat truss shaped punching shear reinforcement (FTSPSR) in enhancing the punching shear capacity of flat slab structure. The numerical analyses were performed using ANSYS Static Structure. The context of this study is the prevention of punching failure by the addition FTSPSR and the effect of varying the number of segments in the truss assembly. A total of four models were constructed for this study. The results showed that the presence of FTSPSR was able to reduce the maximum deflection in the range of 5.33–10.57%. In addition, model with 6 segments in the truss assembly performed better than the rest of the models. The ability of the novel FTSPSR to reduce the maximum deflection can be considered as a practical solution enhance the punching shear capacity and failure of flat slab structure.

S. Salehuddin, S. S. Zaini, W. K. Chan

Compressive Strength and Microstructural Characteristics of Binary Blended Cement Mortar Containing Palm Oil Fuel Ash

The use of non-traditional cement replacement materials such as POFA in concrete has attracted many researchers, likewise this study attempted to keep investigating the ability of utilizing the ultra-fine treated palm oil fuel ash (u-TPOFA) as supplementary cementitious materials (SCMs) in Portland cement mortar. The u-TPOFA was used as SCM to produce binary blended cement mortar (BBCM) at different replacement levels of 30, 40, 50 and 60 wt% of ordinary Portland cement (OPC). The compressive strength (CS) was evaluated for all the cured samples at various ages of 3, 7, 14, and 28 days. The test results showed that the CS development improved with curing age as expected in all cases and a clear influence of u-TPOFA replacement levels on CS of the BBCM was observed. The CS at early ages of the BBCM was lower than the control binder mortar (CBM). However, the CS started to increase after 7 days of curing. The highest CS among all the BBCM was observed with u-TPOFA replacement level of 30 wt% from OPC which achieves 81.7 MPa at 28 days, whereas the CBM registers the highest CS of 83.73 MPa. The results for the CS concur with the phase changes based on XRD and TG analyses. The changes in CS was as a result of the formation of more C-S-H and C-A-S-H gel binders and less Ca(OH)2 content remained in the structure.

Ramzi J. Shaladi, Megat Azmi Megat Johari, Zainal Arifin Ahmad, M. J. A. Mijarsh

Characterization of Aerobic Granular Sludge (AGS) Formation During Start-Up Phase for Leachate Treatment

The treatment of landfill leachate at Pulau Burung, Penang was investigated by applying aerobic granular sludge (AGS) during Start-up. The AGS was grown from a lab-scale with 10 L working volume of sequencing batch reactor (SBR). An achievement of AGS reactors in treatment and effluent quality shows the soluble chemical oxygen demand (CODs) have a small difference with total chemical oxygen demand (CODt) as an effluent quality parameter. In the biological process, a beginning rate of oxygen uptake rate (OUR) was fluctuates, the granules reached maximum value on day 47 with 0.85 (mg O2/L/min) that shows the maximum value due to microbes are quickly growing and reproducing. The sludge retention time (SRT) was conducted in a range of 3–25 d, fluctuate between days 0 and 50 that indicates the SBR system was unstable and immature aerobic granules until day 50. The AGS morphology shows although the granules not matured yet during Start-up but the settling properties exhibited at 47 days indicating good settleability when obtained the sludge volume index (SVI30) between 50 and 80 mL/g. The efficiencies of ammonium removal is above 95% from days 30 to 50 with pH value of 7.9–8.2 but adversely when pH value more than 8.5.

Nur Ain Hamiruddin, Nik Azimatolakma Awang

The Influence of Communication on the Success Design of High-Rise Residential Building on Surabaya

The success of a construction project depends on the successful design. The approach in building design considers to create more sustainable designs. However, designers face several factors that reduce the success rate of the design, that are the design model and the method used. One of the ways to manage this problem is combining all information and systems for the best design. This study analyzes the influence of communication among stakeholder in design process, to the successful design of building design. Data was collected by distributing questionnaires to 37 respondents from design consultants in Surabaya who involved in several building design. Furthermore, a correlation analysis is conducted to analyze the effect of communication on a successful design. The result is verified by interview. The results of the analysis found that communication does not significantly affect to the successful design. The findings of this study are expected to give more benefits to design actors, so the successful design will be increased.

D. Listyaningsih, C. Utomo, M. A. Rohman

Evaluation of Human Factors Influencing Labor Productivity in Construction Project

Construction labor productivity is a crucial measurement of productivity where there is a relationship between the unit output of the labors with their work hours spent in the period of the output progress. Productivity of labors is directly related to human performance, which can be influenced by human factors. The main aim of this study is to evaluate the human factors influencing labor productivity in construction projects at Bukit Mertajam, Pulau Pinang, Malaysia. The research study has identified and evaluated five human factors, which are motivational, skills, communication, work culture and leadership through the literature review. The research method adopted was involving distribution of structured questionnaire and analyzed using IBM SPSS statistic software. The conclusion of the study indicated that all the human factors are considered very significant to the labor productivity in construction project. The five human factors were ranked from the most important to the least important based on the relative important index (RII) and the rank are presented as follows: communication aspect, work culture aspect, motivational aspect, leadership aspect and skills aspect.

Nor Janna Tammy, Muhammad Mazasry Medani, Rozaini Ramli, Juzailah Nur Yunus, Raja Nor Husna Raja Mohd Noor

Seismic Performance of Soft Storey Reinforced Concrete Buildings in Ranau, Sabah Subjected to Design Seismic Load Stipulated in Malaysia National Annex to Eurocode 8

Staff quarters of S.M.K. Ranau and officer quarters of Hospital Ranau, which are the soft storey RC buildings, were severely damaged during a M6.0 Sabah earthquake on 5 June 2015 and were repaired in 2016. Following up, a M5.2 earthquake struck at Ranau, Sabah on 8 March 2018. Due to the buildings are non-seismically designed, the seismic performance of both buildings has not been assessed. Hence, this paper discusses the seismic performance of both buildings subjected to design seismic load stipulated in Malaysia National Annex to Eurocode 8. Computational analyses were performed using ETABS based on the architectural plans and on-site measurement. The simulation models were verified with the measured microtremor data. Seismic performance of both buildings under the design load were obtained by using modal response spectrum analysis. Under the design acceleration of 0.16 g, the maximum interstorey drift occurs at the first floor due to soft storey effect. The maximum interstorey drift for the staff quarters of S.M.K. Ranau has exceeded the damage limitation as specified in Eurocode 8, which is 0.005 mm/mm.

Kar Meng Ho, Tze Liang Lau

Morphology and Elemental Component of PM2.5 at a School Located Near Industrial Area in Malaysia

Fine particles are recognized as one of the main air pollutants that could give negative effects on human health and air quality status. Increase in amount of industrial activities and vehicle could enhance the number of possible sources of PM2.5. This may increase the concentration of PM2.5 for both ambient and inside the building including school. Morphological properties and elemental composition are two components that role significantly in determination of potential sources of particulate matter. Thus, in this research, physical characteristic and elemental component for indoor and outdoor PM2.5 was determined by using Field Emission Scanning Electron Microscopy coupled with energy dispersive X-ray (FESEM-EDX). Results show that there is significant (p < 0.05) relationship between indoor and outdoor PM2.5 concentrations at this selected school with correlation coefficients, r = 0.376. For the morphology and elemental composition analysis, it shows that there are similar shapes of indoor and ambient PM2.5 which irregular shaped and transition metal particles. For the elemental components, range for indoor elements of PM2.5 is O > Si > Ca > C > Na > Mg > Al > Cl and for outdoor PM2.5, the range is O > Si > Na > Ca > Ba > Al > Mg > K > Cl. Therefore, effect of outdoor towards indoor PM2.5 had been significantly identified in this school classroom.

Azrin Suroto, Noor Faizah Fitri Md. Yusof, Nur Amanina Ramli, Syabiha Shith

Structural Response of Building in Ranau, Kota Kinabalu and Lahad Datu, Sabah Under Different Earthquake Scenarios

In June 2015 Malaysia experienced the strongest earthquake in recent years as a magnitude 6.0 earthquake struck Ranau and damaged many buildings in the region of Ranau and Kundasang. Since this earthquake event, seismic design for East Malaysia has become a concern for many engineers and researchers to prevent seismic damage of important structures and infrastructures in the future. This paper covers the structural analysis of a typical four storey reinforced concrete building in three main cities of Sabah namely Ranau, Kota Kinabalu and Lahad Datu. Four earthquake scenarios were considered in the structural analysis including two largest historical earthquakes and two forecast earthquakes. It is found that out of the three cities included in this study, building in Lahad Datu has the most drastic structural response followed by Ranau and Kota Kinabalu. Based on the result of this study, buildings in Ranau and Lahad Datu is expected to experience damage in forecast earthquake. Assessment and retrofitting of important building is required to increase seismic capacity of buildings.

Zheng Yang Khoo, Tze Liang Lau

Walking Induced Floor Vibration on Glulam Timber Floor

The aim of this research is to determine the vibration behavior due to walking loads. The floor was constructed using glued laminate (glulam) timber with 6 m span length. The vibration issues may occur due to lightweight and long span of the floor when the load induced on the floor either walking of jumping load. The occupants may feel the vibration of the floor and cause discomfort and unsafe feeling for the occupants of the building. The main factor that contributes to the increase in the annoying levels of floor vibrations is a low natural frequency of the floor because of long-span and lightweight construction. Therefore, the modal testing was performed to determine the vibration behavior of the floor due to walking induced load. A group of people was walking on the floor and the accelerometer was attached to the floor to record the accelerations. The accelerations data was analysed using ARTeMis software package to determine the natural frequency and mode shape of the floor. The natural frequencies that obtained is ranging from 3.47 to 5.92 Hz, which below the 8 Hz limitation according to Eurocode 5 [2]. Hence, the building is considered as low frequency building, and this explains the excessive vibrations felt by occupants of the building.

N. H. Abd Ghafar, I. Z. Shamsul Kamar, E. C. David Yeoh, H. B. Koh

Thermal Comfort Study Using CFD Analysis in Residential House with Mechanical Ventilation System

Combination of natural and mechanical ventilation is defined as a hybrid ventilation system. This system has drawn attention in indoor thermal comfort. This paper presents a CFD analysis for thermal comfort study of a residential house model. Different scenarios given to the model to evaluate the effect of the mechanical ventilation system of ceiling fan assisted the air flow and natural ventilation in indoor thermal comfort. Predictive Mean Vote (PMV) as in ASHRAE 55 and the thermal comfort (Tc) as suggested in MS 2680:2017 were calculated. From the study, it is found that there is an improvement value of PMV value by +0.1 to +0.2 by having ceiling fans as indoor assisted airflow.

Fathoni Usman, Ahmad Ridzuan Abu Bakar

Flood Hazard Map of Upper Sungai Langat Using HEC-RAS

Hulu Langat district, which is located in Selangor was severely affected by flood. The study area was focused on the upper Sungai Langat basin area where main cities such as Kajang, Bangi, Seri Kembangan and Dengkil are situated. These cities which are located at the downstream of upper Sungai Langat were frequently inundated during heavy rainfall. This scenario had caused a nuisance to the people surrounding the inundation area. Thus, the objective of this study was to produce a flood hazard map by using HEC-RAS model. DEM data of 1 arc-second resolution was used in the HEC-RAS model. Observed discharge data were obtained from DID. Five selected events with discharge value were simulated in 2D using the HEC-RAS model to produce inundation boundary map. The inundation boundary map was compared between simulated and observed discharge value. The result shows that the map produced for both simulated and observed discharge data were almost similar. 100 years ARI for upper Sungai Langat was designed based on MSMA. Peak discharge of 426 m3/s had inundated 93 km2 area of the upper Sungai Langat with maximum depth of 7.14 m. This study had successfully produced flood hazard map.

Siti Multazimah Mohamad Faudzi, Ismail Abustan, Nuridah Sabtu, Muhammad Khairi A. Wahab

Modeling the Fate of Phenol in Moving Bed Biofilm Reactor Sewage Treatment Plant

Phenol is one of a major pollutant existing in the wastewaters from several industrial activities. Biological removal of the phenolic compounds at full scale treatment plant is very complicated processes. This study investigates the fate of phenol biodegradation in moving bed biofilm reactor sewage treatment plant (MBBR-STP) was investigated. A computer-based mechanistic model, TOXCHEM V4.1, and as well as sensitivity analysis were used to predicts the fate of phenol biodegradation in MBBR-STP. The results showed that MBBR-STP has successfully achieved removal efficiency of 90%, 87%, 100%, 89%, 48%, 90%, and 96% for COD and BOD5, PO4, H2S, oil and grease, SO4, NH4, TSS, and phenol, respectively. However, a high nitrate (NO3) concentration of 60 mg/L was produced, indicating the occurrence of nitrification process. The phenol fate analysis demonstrated that 0.3, 0.5, 6, 93.2% went for volatilization, sorption, untreated and biodegradation, respectively. Nevertheless, the sensitivity analysis indicated that increasing the influent flow rate from 200 to 1000 m3/day has reduced biodegradability of phenol from 96 to 82%, respectively, whereas increasing MLSS concentration 500–6000 mg/L incorporated resilient sorption and degradation processes by 0.2–66% and 93–34%, respectively, and MBBR media fill fraction of 88% achieved about 100% phenol removal. The results conclude that MBBR-STP is efficient in removing phenol, and the TOXCHEM V4.1 has successfully predict the fate of phenol.

Haider M. Zwain, Mohammadtaghi Vakili, Ahmed M. Faris, Irvan Dahlan

Numerical Simulation of the Cascade Aerator in Removing Iron and Manganese

The cascade container is also used as an effective method, low cost for treating groundwater. In this study, the Boltzmann Lattice Method (LBM) is used to investigate ventilation processes in the newly designed cascade aerator model. For new cascade containers, different dimensions have been used to determine the best designs that can reduce the concentration of iron and manganese. Two LBM simulations, and two sets of experiments were performed, and the velocity and pressure velocities were calculated. Based on the findings, it is shown that LBM’s initial data, and experimental data corresponds to each other in terms of velocity distribution. In addition, it is also found that water velocity has a significant effect on the effectiveness of ventilation. The cavitation destroys the overflow structure of the surge, and the oxidation process reduces iron and manganese in water by increasing dissolved oxygen. The dissolved oxygen concentration increased from 0.8 to 1.4 mg/L for Model A, and from 0.7 to 1.2 mg/L for Model B. The velocity increases due to angular changes along the main flow direction of the water, and the highest velocity is at point D tin. The results of simulation and experiments for Set A and Set B indicate good agreement in the velocity obtained. The percentage of errors between simulation results achieved is less than 11%. It is clear that the LBM simulation can determine the speed of water accurately on jump accuracy. From this study, it is shown that the velocity increases with the main flow in the flow. On the contrary, pressure decreases with increased water speed. Possible cavitation occurs when the pressure is almost negative, or negative; then the velocity will be higher. Thus, the velocity affects the efficiency of the aeration and the dissipation of tin energy.

Rhahimi Jamil, M. A. Z. Mohd Remy Rozainy, Mohd Nordin Adlan, Mohamad Aizat Abas

Construct Reliability of Structural Equation Modelling (SEM) Exploratory Factor Analysis for a Distracted Driving Behavior Survey

This paper presents an exploratory factor analysis (EFA) of a road safety behavior survey instrument prior to be used for collecting a Structural Equation Modelling (SEM) data. Through a self-administered survey, the data obtained from 100 respondents were analyzed using EFA to measure the survey instrument reliability. The questionnaire consisted of 14 items with responses recorded on a 10-point Likert scale. The results indicated that Kaiser-Meyer-Olkin values obtained for the three constructs measured, Road Violations, Cognitive Errors and Action Errors were 0.767, 0.865 and 0.872 respectively. For Bartlett’s Test of Sphericity, the results were found to be statistically significant. In addition, the Cronbach’s alpha was 0.922 (road violations), 0.959 (cognitive error) and 0.958 (action errors) which strongly suggest that all three constructs were within the required range of internal consistency. The results indicate that the questionnaire is valid and reliable tool for measuring driving errors due to distracted driving behavior.

M. R. Kabit, M. M. S. Lee, N. Zulkiply
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