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2023 | Buch

Proceedings of the Canadian Society of Civil Engineering Annual Conference 2021

CSCE21 General Track Volume 1

herausgegeben von: Scott Walbridge, Mazdak Nik-Bakht, Kelvin Tsun Wai Ng, Manas Shome, M. Shahria Alam, Ashraf el Damatty, Gordon Lovegrove

Verlag: Springer Nature Singapore

Buchreihe : Lecture Notes in Civil Engineering


Über dieses Buch

This book comprises the proceedings of the Annual Conference of the Canadian Society of Civil Engineering 2021. The contents of this volume focus on specialty conferences in construction, environmental, hydrotechnical, materials, structures, transportation engineering, etc. This volume will prove a valuable resource for those in academia and industry.


Mathematical Modelling of the Bearing Capacity of Sibu (Sarawak) Area Peat for Unpaved Road Construction

Peat soils are highly organic soft soils. In engineering terms, they are considered problematic soils due to their high compressibility, high organic content, low shear strength and high moisture contents. These soils constitute a large portion of the land area in the Malaysian state of Sarawak and in its Sibu region in particular. Construction on such soils is often difficult and unpredictable. It is desired to implement a prediction strategy whereby engineers can foresee the shear strength of such soils for future unpaved road construction considerations. As such, a research program was devised to use 3 mathematical models to predict the strength of local Sibu area peats. The models used are: Love et al. (Can Geotech J 24:611–622, 1987, [15]), Barenberg (Design procedures for soil-fabric-aggregate systems with Mirafi 500X fabric, Civil Engineering Studies, Department of Civil Engineering, University of Illinois, Illinois, USA, 1980, [2]) and Giroud and Han (J Geotech Geoenviron Eng 130:787–797, 2004, [5]). For comparison with the theoretical models, peat was sampled from Sibu, from the area near Tun Zaidi Stadium. Results show that Barenberg (Design procedures for soil-fabric-aggregate systems with Mirafi 500X fabric, Civil Engineering Studies, Department of Civil Engineering, University of Illinois, Illinois, USA, 1980, [2]) and Giroud and Han (J Geotech Geoenviron Eng 130:787–797, 2004, [5]) models provided the lowest bearing capacity results in comparison to Love et al. (Can Geotech J 24:611–622, 1987, [15]). Therefore the former two can be considered for any conservative bearing capacity design involving local Sibu (Sarawak) area peaty soils. Generally, these local peaty soils can be used as subgrades for unpaved roads, taking into consideration the local conditions of the study.

Ali A. Mahmood, T. G. Lee
Sustainable Stabilization of Peat: A Literature Study

Peat lands cover large areas around the world in several countries, such as Canada, the United States, Malaysia, Finland and others. As the World population increases, land developers have increased their demand for land for future development. As a consequence, engineers are forced to find ways to treat peatland areas to make them suitable for construction purposes. Soil stabilization is a method that is relatively more economic than other methods in treating peaty soils. Soil stabilization is a process that enhances the properties of soils by altering their physical and chemical characteristics. Stabilization is still used as the most economic and efficient method to improve soil characteristics. This study investigated the various waste materials used in the sustainable stabilization of peat and other soil types. Based on the findings, it is suggested that the engineering properties of stabilized peat need to be further investigated. Since eggshell powder is a waste that is predominant almost everywhere, it is further suggested that the leaching, shear, compaction and consolidation properties of peat-eggshell powder matrices need to be studied.

Ali A. Mahmood, T. Y. Lin, J. K. Zhi
Coxwell Bypass Tunnel—Project Update Mid-Construction

The City of Toronto (Toronto) has developed a comprehensive Wet Weather Flow Master Plan to address degraded environmental conditions in the Lower Don River. The Plan includes an integrated system of tunnels and storage tanks to intercept these wet weather flows, along with key infrastructure upgrades at Ashbridges Bay Treatment Plant (ABTP). It is referred to as the Don River and Central Waterfront and Connected Projects (DRCW Project). The DRCW Project consists of five substantial infrastructure projects that, working together, will significantly improve the water quality in the Lower Don River, Taylor-Massey Creek and along Toronto's Inner Harbour. Toronto engaged Black & Veatch, in association with R.V. Anderson Associates (BV/RVA) and North Tunnel Constructors (JayDee Canada, Michels Canada, and C&M McNally Tunnel Constructors) to deliver the Coxwell Bypass Tunnel (CBT) project, which is one of three tunnels that form the backbone of the DRCW Project. The CBT is a fully deep-rock tunnel 10.5 km long by 6.3 m finished diameter and includes five deep-rock WWF storage shafts, 11 deep-rock drop shafts and deaeration/adit tunnels, and two at-grade sewer connection structures. On average, the five WWF shafts are 20 m inner diameter by 50 m deep. The CBT was tendered in late-2017 and awarded in early-2018. Construction is underway with a Tunnel Boring Machine in a single pass with a precast concrete tunnel lining. This paper provides an update on construction of the CBT, and as of January 2021, the project is approximately 60% complete.

M. Bruder, T. Chiesa, D. Cressman
A Brief History of the Middle Road Bridge

The Middle Road Bridge, constructed in 1909 on present-day Sherway Drive to span Etobicoke Creek between Toronto and Mississauga, was recognized as a CSCE Civil Engineering Historic Site in 2009. The official CSCE plaque for this structure will be unveiled at the 2021 Annual Conference and subsequently installed on site. The Toronto firm Barber & Young designed the bridge, the first reinforced-concrete tied-arch-truss (or “rainbow”) bridge built in North America. The paper describes some of the design and construction innovations in the structure and the professional lives of James Franklin Barber (1875–1945) and Clarence Richard Young (1869–1964), who left the partnership in 1911 to become Professor of Civil Engineering at the University of Toronto and, subsequently, Dean of the Faculty of Applied Science and Engineering from 1941 to 1949.

F. Michael Bartlett
Accessibility for All: A Report from the CSCE President’s Task Force on Accessibility

The UN High Commission on the Rights of Persons with Disabilities, to which Canada is a signatory, focuses on the right to a full and complete life in the community supported by accessible infrastructure yet the role of the civil engineering profession in supporting this right has been largely undefined. The CSCE formed its President’s Task Force on Accessibility and has been active in trying to advance accessibility as a foundation for all civil infrastructure planning and design. Discussions held at CSCE 2018 and 2019 Annual Conferences generated many ideas and much support. While many engineers recognize their role in outdoor infrastructure, most leave the building envelope and interior design to architects. This paper summarizes the current situation with regards to civil infrastructure, successes and gaps, highlights the consideration engineers should include in planning and design, and also the advocacy role that civil engineers can and must play in the planning, design and operation of civil infrastructure, such as Universal Design concepts, updated standards and codes, and small design changes that can result in big improvements in daily life for many. All of this is consistent with the Canadian Engineer’s Iron Ring obligation to society. Some of the recent work of the President’s Task Force will be summarized. Accessibility in civil infrastructure need not be too complex, and is not too expensive. It is time to embrace it fully as professionals.

A. Perks, J. Gillis, T. Hanson, K. Haralampides, G. Hewus, A. Jrade, A. Khan, G. Lovegrove, B. Meyerhoffer, S. Mirza, C. Mulligan, S. Tighe, L. Waugh
Performance Evaluation of Gravel Runway Operation and Maintenance in the Arctic Region of Canada

Diversified aboriginal cultures, abundant natural resources, and unique climate and landforms are emblematic of the arctic region in Canada. Due to the inaccessible location and severely harsh climate conditions, air transportation is the most common means of getting supplies in and providing people mobility. According to Transport Canada, eighty percent of remote northern airports are using gravel runways, but severe issues arise while maintaining their operations, such as rutting, frost action, segregation, etc. Therefore, gravel runways require considerable upkeep to ensure that safe conditions are maintained for aircraft landing and taking off. This study herein focuses on investigating the operation and maintenance procedures at a remote representative airport in the arctic region. Data for air traffic characteristics, climate conditions, and current maintenance and repair practices were collected and analyzed. Field tests on the distress, roughness, friction, density, and bearing strength were conducted to evaluate the runway surface conditions. Lab characterizations of the on-site gravel materials, including gradation, compaction, and bearing strength, were also performed to compare some of the in-situ test results and identify issues in the maintenance activities. Finally, based on the analysis results, this study provides comments and recommendations to improve gravel runway operation and maintenance in the arctic region of Canada in the future.

Guangyuan Zhao, Paula Barbi, Susan Tighe
Application of Integrated Project Delivery (IPD) in Egypt: Implementation and Challenges

Traditional contractual delivery methods are perceived to have flaws that become more apparent when projects increase in size or complexity. The Integrated Project Delivery (IPD) is a contractual framework that features enhanced collaboration, risk and reward sharing, and early contractor involvement under a single contract among the major project parties (owner, engineer and contractor). This delivery methodology became more apparent due to the increasing level of complexity of the construction projects and the need for efficient risk and cost sharing to enhance project performance and foster collaboration rather than the traditional hostility. IPD methodology has proven promising results in many parts of the world. However, it has not been applied in Egypt. In addition, no significant investigations have been made to address the adaptability of the Egyptian construction sector to the IPD delivery. The objective of this research is to analyze the Egyptian market’s preparedness to the adoption of IPD delivery. First, a thorough literature review was carried out to identify common barriers and enablers of applying IPD in construction. Second, a survey was carried out to assess and rank such barriers and enablers as specific to the Egyptian construction sector. Finally, through structured interviews with contract experts, strategies and guidelines were devised to be used by Egyptian owners, consultants, and contractors who have the intent of implementing the IPD delivery in their projects. The findings reveal that the main barriers to implementing IPD stem from cultural resistance to the new system and lack of knowledge about it. In addition, even if owners overcome their cultural barriers and intend to apply IPD in their projects, there is a significant shortage of IPD experts in the country to help them with that. The results and subsequent strategies outlined by the research are expected to help the construction industry in Egypt gain more depth on the benefits and application of IPD. Consequently, the authors hope that such study encourages the adoption of IPD in Egyptian projects so that they can healthier construction in terms of better collaboration, less cost overruns, enhanced schedule performance, and minimal waste.

Mohamed Sherif, Ibrahim Abotaleb
Problem-Based Learning for Undergraduate Civil Engineering Education in South Africa- a Methodological Approach

Civil engineering graduates need to be competent to solve socio-economic and environmental as well as engineering problems. The universities are responsible for offering a pedagogical method that enables students to learn deeply and become competent. Arguments have emerged that Problem Based Learning (PBL) in engineering education in general and particularly in civil engineering could make the students engage in learning effectively and become competent. However, PBL in engineering or civil engineering education in South Africa is not prevalent. No benchmark of the way it should be delivered is available. Therefore, the study aimed to develop a methodological approach so that PBL can be effectively practised and offered in undergraduate civil engineering education in the universities of South Africa. The study relied on the action learning research framework and perceptions of different stakeholders who participated in the PBL programmes. Findings suggest that five sequential stages involving sequential steps in each stage can assist in the effective and successful implementation of the PBL and attainment of learning outcomes. Also, certain steps that include the selection of problems in alignment with learning outcomes, formation and preparation of heterogenous teams to work on a complex problem, identification sub-problems, finalisation of the design brief, generation of ideas and engineering concepts, transformation of ideas to alternate solutions (design or products), evaluation of the alternate solutions, design of sustainable engineering solutions or creation of the sustainable products and showcasing the design or product for evaluation are of significance and can be treated milestones in delivering the PBL.

D. Das
Optimization of Multi-Skilled Labor to Minimize Lost Man-Hours in Construction Projects

The current practice of single-skilled labor allocation in construction schedules poses some inefficiencies. In such practice, at any instance in the project lifecycle, some of the workforce become idle waiting for other labor types to finish work. Companies may allocate idle workers to other projects and return them back to their original project when needed again. This complicates the resource management process and causes a lot of confusion and is not often performed successfully. Project managers, many times, may also keep the idle workforce at their projects because they will be needed in a later stage and pay them in their idle days; which adds unnecessary cost. Another solution would be doing continuous hiring and laying off; which has severe negative impacts on projects and firms. On the other hand, some research discussed the idea of “multi-skilled” labor, where a number of workers on site may have enough experience to carry out different types of tasks. Multi-skilling decreases inefficiencies and ensures a smooth and continuous progress of projects whilst maintaining the workforce and keeping their idle time to a minimum. Multi-skilling could be also used to speed up progress in construction schedules. The objective of this research is to develop a framework for optimizing training and allocating multi-skilled labor in construction projects. In doing so it is expected to minimize idle times of labor by allocating them to ongoing activities.

A. Saleh, I. Abotaleb, O. Hosny
A Brief Historical Review of Gardiner Dam and the South Saskatchewan River Project

Gardiner Dam, which is the most significant component of the South Saskatchewan River Project, recently celebrated its 50th anniversary following its completion in 1967. The 64 m high, rolled earthfill dam was among the largest of its type in the world at the time of its construction. There were many challenges to be addressed in bringing the project to fruition, including those of both a technical and a political nature. In short, the dam, and indeed the entire project, is testimony to the successful completion of an important Prairie water resource initiative by a talented group of design and construction engineers. The project has brought tremendous benefits to an important semi-arid agricultural region located in the heart of the Prairies of Canada. Here, an overview is provided of the South Saskatchewan River Project, including some historical context, the key project components, brief mention of a number of the key players involved in the project, aspects of the political intrigue that occurred prior to project initiation, highlights of the design and construction challenges faced with the project, particularly that of Gardiner Dam, mention of a few project impacts, and a synopsis of the several benefits of the project as they have been realized over the 50-year period since its completion.

Jim Kells, Cal Sexsmith
Evidence-Based Water Loss Management: Development and Deployment of a Mobile DMA Testing Unit

There is a strong connection between water supply and energy consumption which, considering trends towards reducing system stresses, provides an opportunity to take advantage of the synergies associated with leakage reduction and energy conservation. In recognition of these synergies, a multi-year project has been initiated in Ontario through funding from the province’s Independent Electricity System Operator to promote water loss reduction practices. The project involves the development and deployment of a mobile testing unit designed as an affordable method to accurately and reliably measure minimum night flow (MNF), an indicator of leakage, into discrete sectors of water distribution systems commonly referred to as district metered areas (DMAs). In addition to flow monitoring, the mobile unit is equipped with a pressure reducing valve (PRV) to directly test the effectiveness of pressure moderation on leakage reduction. More broadly, the project involves the collection of data across 22 DMA sites in Ontario with results informing the development and application of evidence-based benchmarking metrics used to assess the performance of DMAs in similar municipalities elsewhere. Moreover, analyses of the project’s testing results, previous DMA work and advanced metering infrastructure (AMI) data are presented to support the establishment of MNF benchmarks (representing healthy systems). While this project is still ongoing, initial successes have proven the mobile testing unit concept and substantial value has already been realized. Accordingly, a case study is featured where exceptional savings were demonstrated and quantified as a result of intervention efforts informed by the project.

B. Jenks, F. Papa, B. Karney
Replacement of the Historic Traffic Bridge in Saskatoon

Originally built in 1907, the Traffic Bridge was Saskatoon’s first bridge to carry vehicular traffic. The Traffic Bridge was designed as a 5-span Parker through truss and came into being when residents of the Village of Nutana agreed to merge with the Town of Saskatoon and the Village of Riversdale to form the City of Saskatoon. The heritage value of the Traffic Bridge lies in its status as a landmark in the community, its form, massing, and location, the engineering technology used (steel truss architecture), and the original concrete piers and abutments. Throughout its 103-year history, the bridge has been used for horse and carriage, streetcar, and modern vehicle use. The bridge was closed in August 2010 due to public safety concerns due to advanced deterioration of critical structural members. In 2010, the City commissioned a needs assessment and planning study of the Traffic Bridge, which investigated multiple alternatives and potential replacement, included extensive public consultation, regulatory review and debate, as well as City Council presentations. Many elements of the existing bridge were to be incorporated into the new bridge. Engineering studies were completed on the existing elements to determine strengths and compatibility with the new structure. City Council and public participation in all aspects of the bridge replacement process were an integral part of this project. A P3 model was used for the design and construction of the replacement bridge. Many challenges presented themselves during the design and construction of the structure and these challenges provided unique resolutions. The construction of the replacement bridge was completed in 2018, and upon completion, the contractor became responsible for the maintenance of the bridge for the following 30 years.

Kelvin DeGrow, Erin Medforth
Quantile Based Probabilistic Characterization of Geotechnical Variables Using Maximum Entropy Principle

In probabilistic reliability analysis and design, critical geotechnical variables such as soil shear strength are usually characterized as random variables in terms of probability density function or cumulative distribution function, of which the type is usually determined from histograms or simply from experience, and the parameters are estimated using the method of moments or the method of maximum likelihood. However, the difficulty in obtaining accurate moment estimates from small samples has been the main impediment to accurately determination of probabilistic models. The present paper proposes a novel probabilistic characterization of soil properties by using quantile functions based on the principle of maximum entropy and probability-weighted moments. Quantile functions are equivalent to the probability distribution of stochastic data since the quantile function is the inverse of the cumulative distribution function. The maximum entropy method is presented to generate a least unbiased quantile function for soil properties from observed soil samples. Due to the use of probability-weighted moments, the entropy-based quantile functions can quantify uncertainties more accurately from samples than probability density functions or cumulative distribution functions. A comparative study between maximum entropy quantile distributions and traditional quantile distributions is conducted to evaluate the performance of quantile distributions. The analytical entropy quantile distribution obtained can be readily used in probabilistic reliability analysis to enhance the accuracy of calculation.

J. Deng, S. Singh
Masonry Construction as a Solution for Healthy and Resilient Buildings: A Life Cycle Thinking Based Evaluation

Accomplishing sustainable construction is a challenging task. Building sustainability entails green building design and construction, assessing both environmental factors and financial benefits. Therefore, subsequent buildings expected to be constructed based on local context and purpose. Moreover, factors such as resource scarcity, climate change, and adaptability are changing the construction industry. Therefore, occupant health and resiliency alongside with TBL have been receiving predominant significance in building construction and operation. Alternative wall construction methods will be compared using a sustainability index. The aim of this research is to examine masonry construction as an environmentally sustainable solution for Institutional (ICI) building construction in Canada. Life Cycle Assessment (LCA) assessment was used to compare popular interior wall construction methods, according to ISO 14044. LCA of alternative interior wall construction techniques conducted using SimaPro software. The comparative results show that masonry construction is the greener construction alternative. The study considered cradle to gate and cradle to grave system boundaries for alternative interior wall construction techniques. Results indicated that the wood stud gypsum wall is the greener technique in the cradle to gate system boundary. In the cradle to grave system boundary, the concrete block-masonry wall is the greener construction technique due to the ability to reuse the waste materials. This research informs the construction sector in enhancing the sustainability of ICI buildings construction.

Kartik Patel, Rajeev Ruparathna
A Web-Based Change Control Management Toolkit for Lump-Sum Turnkey Contractors: Transformation to Third Generation

Project changes are almost inevitable at all stages of the projects’ lifecycles. Mismanaging these changes is one of the key contributing factors leading to project hardships, such as profit erosion, scope creep, and time slippages. Such adversity is amplified for contractors engaging in lump-sum turnkey “LSTK” projects. Contractors encounter a higher level of financial exposure in LSTK projects as most impacts resulting from project changes are allocated on their liability. Despite its importance, few contractors engaging in LSTK projects have effective project change management systems “CMS”. LSTK contractors are faced with numerous barriers whilst attempting to implement the CMS techniques such as the required extensive amount of efforts, time consumption, cost of applications, as well as improper circulation of data; thus, the paper provides customized recommendations for developing the working steps of the CMS for LSTK contractors. During implementation, other challenges emerge for LSTK contractors, namely the mobility of team members, redundant working steps, and non-utilization of the closed projects’ CMS data for the company’s continuous improvements. Therefore, a web-based project change control & management toolkit “WCCMT” has been designed and developed for LSTK contractors engaging in Engineering, Procurement, and Construction “EPC” projects. It has been adopted by an EPC contractor under which the toolkit was developed and tested. It aims to facilitate the workflow and data circulation which would shorten the CMS cycle time and improving the contractor’s system functionality. It also centralizes and analyzes the data of the registered projects for continuous improvement of the contractor’s performance.

Ahmed Ezeldin, Ahmed Omran
Comparison of the Cantilever Bending Behavior of Polygonal and Rectangular Hollow Structural Sections

Thin-walled rectangular hollow structural sections are less efficient when dealing with long un-braced deep beams that require high bending stiffness due to their susceptibility to local buckling. Consequently, the polygonal hollow section (PHS) which approximates an oval hollow section (OHS) and a rectangular hollow section (RHS) was proposed. Previous studies have shown the PHS has almost four times the rotational capacity of comparable RHS and the potential to minimize local buckling in thin-walled hollow sections. However, these studies only compared the PHS to RHS via four-point and three-point bending tests. As a result, a series of experimental cantilever bending tests using PHS and RHS beams were completed. The purpose of the cantilever tests was to compare the bending moments, stresses, strains and deflections of the PHS and RHS beams. The results showed that in the linear range, the PHS beams experience higher deflections than the RHS beams due to their lower moment of inertia, especially for the larger PHS and RHS beams. However, for the smaller beams that experienced higher strains in the regions of higher bending moments, the results showed that the PHS beams experienced less deformation than the RHS beams. It is likely that the bends of the PHS helped minimize ovalization of its cross-section, which minimised deformation. Furthermore, the results showed lateral torsional bending is not significant for hollow structural section beams as the lateral deflections recorded at the top and bottom of all the beams during the bending tests were minimal, <2 mm.

J. Kabanda, C. MacDougall
Interactive Expert System for Budgeting World Bank Consultancy Projects

Cost estimating is a key component of the budgeting of any project, conventional approaches may result in uncertainty and usually do not utilize the knowledge of past projects. Ideally, performing cost estimation under the best predictions of the relevant future conditions is the best approach of economic analysis to evaluate the optimum value for money. With the rise of Artificial Intelligence techniques, there are several Machine Learning (ML) methods that are being studied to capitalize on accuracy gains with regards to cost estimating techniques during the tendering phase. This research aims at developing an expert system that determines the rough order of magnitude for budgeting with an expected range of 30–35% leeway, to forecast the budget of consultancy services of World Bank projects through regression by classification using the Ensemble method. The expert system utilizes advanced ML methods to be able to generate accurate forecasts based on a rigorous database of past projects. The model was trained to identify the influential factors that affect the cost of the services in accordance with the published data related to the project and contract award. Among the studied variables are; sector, procurement method, environmental category, procurement type, region, and overall project budget. The dataset was used as inputs for over 80,000 consultancy contracts globally over the last 14 years. A web interface was then created where the cost estimates of consultancy services tendered by the World Bank are determined. The model developed showed a 72% acceptance rate in terms of model accuracy.

Y. Rafat, S. Ezeldin
Fire Performance of Ultra-High Performance Concrete

Ultra-High-Performance Concrete (UHPC) is a relatively new form of concrete, with improved compressive and tensile strengths compared to traditional reinforced concrete. As it is a younger material, knowledge gaps exist in certain aspects such as fire performance. The dense microstructure of UHPC contributes to its high strength, however it also requires a special mix design consideration to enable dissipation of vapour pressure to avoid explosive spalling during fires. This paper presents a review of the studies on the fire performance of UHPC and identifies the areas that require further investigation. Findings show that, when used alone, steel fibres do not improve the fire resistance of UHPC. Synthetic fibres, such as polypropylene (PP) fibres, have been found to be more effective in improving the fire performance and preventing explosive spalling. The review shows that little attention has been paid to studying the performance of UHPC during exposure to elevated temperature, especially on the structural level. In response to the identified research gaps, a comprehensive research project at Queen’s University has been initiated to assess the fire performance of double-wythe insulated (DWI) wall panels made with UHPC. Prior to performing a set of full-scale fire tests, smaller-scale compressive and tensile concrete specimens reinforced with various amounts and combinations of polyvinyl-alcohol (PVA) fibres and PP fibres will be tested at temperatures as high as 500 °C under steady-state and transient temperature heating regimes.

B. MacDougall, H. Hajiloo, S. Sarhat, J. Kabanda, M. F. Green
The Niagara Power Generating Stations: A Major Milestone in the Use of Hydro-Electrical Energy

The Niagara power generating stations represent formidable historic Canadian and American milestones in the generation of hydroelectric power. In particular, the turn-of-the-last century stations were among the first to generate alternating current (AC) power, which is more readily transmitted than direct current (DC) and has since become the worldwide standard. Unique design features prevent ice from entering the conduits and penstocks and so prevent damage to the turbines. The careful consideration of the aesthetics of these installations has preserved the immense popularity of Niagara Falls as an international tourist destination. Their designation as Canadian Society for Civil Engineering National Civil Engineering Historic Sites is richly deserved.

Ali A. Mahmood, M. Bartlett
Life Cycle Costing Based Capital Asset Planning Method for Bridge Infrastructure

Municipal infrastructure is a major component of the socio-economic environment of a region. Hence, sustainable infrastructure management is a challenge for any municipality. Canadian municipalities have realized the importance of developing strategies to manage the infrastructure assets that they own and operate proactively. Predicting and budgeting future maintenance of the aforementioned infrastructure is a key responsibility of a municipal infrastructure manager. Traditionally, preventive approaches have been used for infrastructure maintenance planning. Thus, the objective of this paper is to develop a predictive budget planning method for bridge infrastructure. Firstly, deterioration matrices and the impact of maintenance methods on the physical condition were determined from past condition assessments. Secondly, the Markov chain principle-based algorithm was applied to simulate the condition of the bridge over a 20-year period. Lastly, the above method was used to determine the maintenance strategy at the lowest life cycle cost. This information was used for capital planning by forecasting future budget requirements. The proposed method provides an efficient way of selecting appropriate maintenance alternatives based on the desired performance level and is able to generate budgets for years to come. This algorithm offers municipal managers an opportunity to analyze uncertainties, generate impact costs over time, and, ultimately, create capital budgets for infrastructure assets.

S. Ngabire, A. Botham, R. Ruparathna
Investigating the Impact of Construction Robots Autonomy Level on Workers’ Cognitive Load

Construction robots are being used for several repetitive, basic tasks in construction sites, and soon it is expected that they will be used in more complicated operations to assist human workers. However, given the dynamic and unstructured nature of construction sites, robots’ engagement in complex tasks requires high intelligence and autonomy levels. While working with highly-automated robots in shared workspaces can result in higher productivity and lower costs, it may not be embraced by many construction workers, resulting in poor performance, safety, and well-being. Therefore, it is critical to profoundly understand workers’ response to imminent autonomous robots before their vast implementation at construction sites. In this context, effective measurement of workers’ cognitive load provides insights into human responses to robotic co-workers. Therefore, this study investigates the impact of autonomy levels of construction robots on workers’ cognitive load using qualitative and quantitative methods. To that end, an experiment was conducted in which subjects performed a masonry task in two different scenarios in collaboration with a semi-autonomous and an autonomous robot. An immersive virtual environment was used as a controlled and safe testbed to examine workers’ cognitive load while working alongside a virtual construction robot. Subjects’ electroencephalography (EEG) signals and questionnaires (NASA-TLX) were collected to assess cognitive load during each scenario. The results indicated that subjects’ cognitive load increased with an increase in the robot autonomy level, suggesting incorporating human factors in designing collaborative robots. The findings can help to determine adequate autonomy levels for seamless human–robot collaboration at construction sites.

S. Shayesteh, H. Jebelli
Understanding Students’ Engagement in Learning Emerging Technologies of Construction Sector: Feasibility of Wearable Physiological Sensing System-Based Monitoring

Considering the imminent ubiquity of emerging technologies in the construction industry, the workforce needs to possess multidisciplinary skills to realize the full potential of incumbent technologies. Despite the importance of education to gain required expertise, there is dearth of in-depth understanding of the effectiveness of current pedagogies. Engagement is an essential aspect of any pedagogical experience, directly affecting knowledge retention. However, the traditional evaluation methods are unsuitable for objectively understanding engagement. Interpretation of physiological response can provide insight into the emotional state of learners. Recent advancements in wearable technologies and physiology offer objective approach to measure the engagement level. In this regard, this study aims to assess the feasibility of wearable physiological sensing technologies for understanding the engagement level of students learning emerging technologies in construction. The potential of electrodermal activity (EDA), photoplethysmography (PPG), and skin temperature (ST) was investigated in detecting the engagement level of students. Ten minutes of biosignals were acquired from 5 students in two different learning experiences (i.e., passive learning through slides and active learning through didactic videos). Different metrics (electrodermal level, the mean value of PPG, mean skin temperature, etc.) were calculated from the time domain and frequency domain to investigate the potential of the suggested biosignals. Results indicated a statistically significant difference in the physiological metrics extracted from biosignals of the student in different learning setups with varying levels of engagement. Findings demonstrated the feasibility of wearable sensors to evaluate the students’ engagement level in their learning of emerging technologies of construction.

A. Ojha, H. Jebelli, M. Sharifironizi
Feasibility Verification of Multimodal Wearable Sensing System for Holistic Health Monitoring of Construction Workers

The unstructured nature of the labor-intensive construction industry negatively affects the health of workers. These challenges require a robust health monitoring approach to accurately monitor workers’ overall health status. Recent advancements in wearable technologies and physiological sensing have provided ample opportunities towards an objective and continuous in-field measurement of workers’ physical and mental status. However, these solutions have mostly focused on a particular health condition. There is a lack of holistic health monitoring to understand the impacts of the construction environment on workers’ health conditions (i.e., physical fatigue, mental stress, and exposure to heat stress). In this regard, the present study investigates the feasibility of a multimodal wearable sensing system to comprehensively monitor construction workers’ overall health status during their ongoing work. To this end, five able-bodied workers were prompted to perform specific construction activities (e.g., roofing, loading/unloading) with light and medium physical intensity while exposed to varying levels of heat stress (i.e., caution level, and danger level). During each task, three biosignals, namely photoplethysmography (PPG), electrodermal activity (EDA), and skin temperature (ST), and were collected from the workers through wearable biosensors. To assess their overall health status, various metrics were extracted from PPG (heart rate, heart rate variability), EDA (electrodermal level), and ST (mean skin temperature). Results of correlation analysis elucidated strong correlation between the extracted physiological metrics with respect to workers’ physical fatigue, mental stress, and heat stress exposure. The findings demonstrated the feasibility of a multimodal sensing system for the holistic health monitoring of construction workers.

A. Ojha, S. Shakerian, M. Habibnezhad, H. Jebelli
Enhanced Robotic Teleoperation in Construction Using a GAN-Based Physiological Signal Augmentation Framework

Communication channels between humans and robots can alleviate safety hazards (collisions, interference) during human–robot collaboration (HRC) at construction sites. Recently, the authors demonstrated the feasibility of improving HRC by using electroencephalogram (EEG) signals to establish hands-free, nonverbal communication. Despite the potential of EEG to provide reliable means of communication, there is a concern regarding the quality of the collection of EEG signals, especially low spatial resolution. EEG signals collected from wearable devices suffer from this problem because the number of electrodes (5–32) is much lower than traditional clinical EEG systems (64–256). More importantly, the low spatial resolution may reduce the reliability of human–robot communication driven by EEG signals. To address this challenge, this study seeks to increase the spatial resolution of EEG signals by proposing a generative adversarial network (GAN)-based data augmentation framework. In it, artificial EEG signals will be produced from actual signals. To examine the feasibility of increasing the spatial resolution of EEG signals for an improved HRC, the EEG dataset of four subjects was collected using a wearable 32-channel device. The results show that the framework can enhance the spatial resolution of the collected dataset by 39.1% by generating realistic artificial signals. It also increased the accuracy of the EEG-based robotic teleoperation by 4.9%. It is expected that increasing the spatial resolution of EEG signals will improve the reliability of EEG-based human–robot communication.

Y. Liu, H. Jebelli
Image Content Analysis of Perceived Race and Gender on Websites of Top Accredited Engineering Schools in Canada

The study analyzed the perceived gender and race present in website images of selected post-secondary institutions with accredited engineering programs. Websites will likely have more influence on applicants' decisions than in the past due to the lack of in-person recruitment events. The study aims to quantify the diversity-related shortcomings of these websites to begin understanding their impacts and promote inclusion. Around half of the individuals featured on institutional and engineering homepages are perceived as women, while less than a quarter of individuals are perceived as BIPOC. This finding highlights the lack of emphasis on racial diversity in marketing materials and constitutes poor representation of the racial diversity present in the engineering student populations. The results aim to inform future qualitative studies on how youths of equity-seeking groups perceive engineering and other STEM disciplines.

Michelle C. Liu, Andrea Atkins
Understanding Material Consumption During Maintenance of Buildings

The longest and most costly part of a facility lifecycle is the operations and maintenance (O&M) phase. Therefore, it is important to implement sustainability principles during maintenance activities, such as reducing material usage. Proper maintenance of a facility impacts the lifecycle sustainability of a project by increasing the usable life of the facility and improving its energy efficiency. Like many building owners, the United States (US) Department of Defense (DoD) has sustainability goals and policies to reduce the environmental impact of their buildings. This study reviewed 28,790 work orders from 272 military office facilities across the US and around the world to reveal material consumption during maintenance and the impact of preventative maintenance (PM) on reducing corrective maintenance (CM) requirements. The study found that heating, ventilation, and air conditioning (HVAC) maintenance consumes the most material per work order, with material accounting for 43% of the average work order cost. Both HVAC and painting had the greatest average material cost per corrective maintenance work order, at $277 and $254 respectively, suggesting a higher consumption of material than other crafts studied. This study contributes to an understanding of the proportion of a typical work order cost that is material cost and to quantifying the relationship between PM and CM. This research applies to office buildings maintenance decisions, particularly material selection. For owners to improve the sustainability of buildings, they must reduce material and energy consumption during facility O&M which starts with design decisions and continues through maintenance prioritization.

D. Weeks, F. Leite
Historical Development of Rammed Earth Construction and Its Use in Canada

Rammed earth (RE) construction is a sustainable building method, using naturally available materials, for laying foundations, and walls typically of low-rise buildings. RE construction requires: compaction of a mixture of damp soil with a suitable proportion of clay, lime, cement, and other binding material. The advantages and disadvantages of RE construction depend on the geographic location, the quality of material, and the difficulty acquiring land-use and funding approvals, but RE structures once constructed have the advantages of being structurally rigid, durable, fire resistant, soundproof, and moisture resistant. In addition, RE construction can be cost effective as compared to structures that are made with other building materials, provided an adequate supply of suitable earth exists onsite or nearby. Owing to its advantages, RE construction has been widely used since ancient times for domestic, agricultural, and monumental public buildings and structures. In this paper, the physical characteristics of RE construction are reviewed, and the history of its use globally and in Canada are discussed.

R. Gupta, B. C. Burrell, M. Garg, A. Gupta, M. Krayenhoff, J. Krayenhoff
Tensile Properties of PET FRP with Bio-Resin Polymer

This study analyses the mechanical behaviour of polyethylene terephthalate fiber-reinforced polymer (PET FRP) made with a bio-resin polymer matrix. The utilized bio-resin is furfuryl alcohol mixed with phthaloyl dichloride catalyst; this selection of resin type, catalyst type, catalyst dose, and curing time was made based on previous investigations. A sheet of PET FRP composite was fabricated following the wet lay-up method. The composite sheet was cut into six coupons (three in the longitudinal direction and three in the transverse direction). The coupons were then tested in uniaxial tension, and the stress–strain relationship was extracted. The stress–strain relationship of the bio-resin PET FRP was found to be nonlinear and consisted of three main stages of linear curves. The elastic modulus at each stage was derived along with the coupon's average yielding stress and ultimate strength. By deriving and presenting the mechanical performance of this newly developed FRP, this study aims to determine whether the composite could be a potentially sustainable alternative to conventionally used FRPs. The two sets of tested coupons had equal strain capacity–which is four times the strain capacity of glass fiber-reinforced (GFRP) composite. Conversely, longitudinally cut coupons had double the strength capacity of transversely cut coupons.

R. Kassab, P. Sadeghian
Three-Point Bending of Sandwich Beams with FRP Facing and PP Honeycomb Core

In this study, two sets of sandwich beams were tested in three-point bending. The sandwich panels were fabricated in a wet layup process. The facing component was made of either polyethylene terephthalate (PET) fiber-reinforced polymer (FRP), or glass fiber reinforced polymer (GFRP). The facing thickness was 3 mm for both PET FRP and GFRP. Polypropylene (PP) in honeycomb structure form, with a density of 80 kg/m3, was used as the core component among all tested beams. The sandwich beam dimensions were consistent at 1,200 mm length, 78 mm width, and 82 mm height. While testing each sandwich beam, the applied load, overall beam deflection, and facing strain were captured at mid-span. The resulting data were processed to produce load–deflection, moment–curvature, and load-strain diagrams. At peak load, bond failure between the walls of the cylindrical tubes within the honeycomb structure occurred; therefore, the failure mode for all tested sandwich beams was attributed to shear failure. The load–deflection relation was nonlinear in both sets, which was derived from the thermoplastic component (PET FRP facing and/or PP core). A nonlinear analytical model was developed and compared to the experimental testing data. The method used for experimental testing and analytical modelling was outlined in this study. The experimental matrix, testing results, and analytical model indicated that the nonlinearity of the sandwich beam's load–deflection relation stems from the facing and core components. In contrast, the nonlinearity of moment–curvature and load-strain relation stems solely from the facing component.

R. Kassab, P. Sadeghian
Identifying the Level of Development of Integrated Urban Infrastructure Management Practices in Chile

Urban infrastructure systems play a key role in society by providing access to basic services, such as clean water and transportation. The management of urban infrastructure systems ensures that these are maintained to minimize failures and provide users with reliable services. As urban infrastructure systems are interdependent, maintenance and rehabilitation activities performed in one system may impact other infrastructure systems. Consequently, an integrative approach is needed to account for the influence of interdependencies on the management of multiple infrastructure systems. This study aims to identify the level of development of integrated infrastructure management practices among Chilean agencies managing water, wastewater, stormwater, and transportation infrastructure. To do so, the authors carried out 10 semi-structured interviews between October 2020 and January 2021 with different stakeholders involved in managing such systems that were qualitatively analyzed. Additionally, to contextualize our results, a comparison is presented with management practices reported to be applied in Canada. Our results show that Chilean agencies are mostly focused on managing infrastructure systems individually and that limited processes exist regarding the integration of multiple infrastructure systems. Moreover, the Chilean context lacks strategic vision, it lacks data to facilitate agencies’ decision-making process, and organizations are highly fragmented. When comparing Chilean agencies’ level of development with Canadian practices, it is emphasized that Chilean agencies are well behind in applying integrated urban infrastructure management practices. Understanding the current practices (or lack thereof) regarding infrastructure management may assist agencies in identifying alternatives to develop plans and implement integrated infrastructure management approaches in the future.

Sebastian Vasquez, Felipe Araya
Methane Gas Refined Fault Theory for Cause of Tectonic Earthquakes

The elastic rebound theory of active geological faults for the cause of tectonic earthquakes has been developed and used for more than 100 years. But it has encountered the inability of earthquake prediction. The author has developed a refined earthquake theory of originality by infilling a certain amount of highly compressed methane gas mass into the deep geological fault zone. The infilling of gas mass makes the fault active and elastic and eventually causes earthquakes along the fault.

Z. Q. Yue
Developing a Comprehensive Relational Database for Optimizing Land Utilization in Sustainable Farming

Over the past few decades, researchers have been studying different approaches to promote self-sustaining communities, especially in developing countries, to combat the formidable challenges of rapid urbanization, climate change, as well as food and energy depletion. While the analysis of previous literature has shown a significant shift towards the design and application of smart data and automated tools in farming and landscaping, there is still a need for comprehensive databases that help users identify efficient and economic approaches pertaining to utilizing a land plot for either open field farming or the use of greenhouses. This study offers an overview of how a comprehensive relational database can be developed and implemented into an automated interface that optimizes the decisions for such operations, through the acquisition and organization of big data in farming and greenhouse construction. The relational database established in this study links different crops with soil types, water and climatic requirements. Furthermore, information regarding the type of greenhouses and their construction requirements is also integrated into the database. This relational database will facilitate the optimal utilization of land through identifying solutions that maximize potential returns while minimizing the life cycle cost and water consumption. Not only will this assist planners and farmers to approach their agricultural operations in the most sustainable manner, but also help them overcome the typical intuitive process of selecting how a land is utilized, which does not necessarily provide optimal return.

O. Hosny, A. El Eslamboly, E. Dorra, K. Tarabieh, I. Abotaleb, M. Amer, M. Farouk, H. Gad, M. Hassan, S. Mansour, A. Abdelgelil, M. Sameh
An Integrated Multi-criteria Decision Making Model for Evaluating Sustainability Rating Systems

Heritage buildings require special attention because of their unique architectural style. Due to the lack of rating systems designed for heritage buildings, this paper presents an assessment tool that considers specific characteristics of heritage buildings. The utilized rating systems worldwide are identified, studied and compared to test their advantages and limitations. As such, a group of attributes is identified to evaluate the current sustainability ratings including site and ecology, material waste reduction, indoor environmental quality, etc. Analytical Hierarchy Process is utilized for interpreting the weights of the attributes. The comparative analysis is carried out using an integrated paradigm that comprises four multi-criteria decision making techniques namely, grey relational analysis, complex proportional assessment, technique for order of preference by similarity to ideal solution and multi-objective optimization on the basis of ratio analysis. Average ranking algorithm is then adopted for the sake of establishing a holistic evaluation of the sustainability rating tools. Results demonstrated that German Sustainable Building Council accomplished the highest ranking while green globe and greenship Indonesia provided the lowest ranking. It was also inferred that these systems failed to deal with heritage buildings. Therefore, it is recommended to develop a system designed specifically for heritage buildings by adjusting related rating systems. It is expected also that the developed model will enable the user to map the main deficiencies in the current sustainability rating systems, which paves way for more comprehensive and efficient rating sustainability heritage rating systems.

A. Al-Sakkaf, E. Mohammed Abdelkader, N. Elshaboury, S. El-Zahab, A. Bagchi, T. Zayed
An Investigation into the Numerical Modelling of Timber at Elevated Temperatures

In Canada, the use of mass timber as a structural material has become more commonplace. A useful tool in the design of structures is structural analysis/finite element modelling programs. These tools are structured around assumptions based on extensive research on the behaviour of structural materials. However, at this time timber is not well understood as a structural material at elevated temperatures. A literature review and research gaps analysis was conducted herein to examine the current underlying theory and capabilities of modelling timber's response to fire. This review illustrates that literature is uncertain and has contradicted itself when discussing the effects of elevated temperatures on both the thermal and mechanical properties of timber. Further, some of the least understood properties in this knowledge gap are density, thermal conductivity, and the tensile properties of timber. Without having a thorough understanding of the material, no numerical model designed can be deemed accurate for general use at this stage without further experimental study. This paper will begin with an overview of past published research on the topics of timber properties at elevated temperatures and the implementation of numerical modelling for fire safety engineering. The purpose of this paper is to discuss the research gaps of timber properties as well as the impact these gaps have on the development of numerical models. The paper concludes with proposed methods to determine the effect of elevated temperatures on the properties of timber and their influence on developing a numerical model.

E. Philion, J. Gales
Mortar Bar Test for Reactive Aggregate Detection: A Review

Cement industry consumes annually around 5% of total industrial energy and results in about 8% of the total global carbon dioxide emissions. Therefore, there is a burgeoning interest in finding alternative binders with lower environmental impacts. Among several promising alternatives, alkali-activated materials (AAMs) are attractive for many researchers. However, there are many concerns about the suitability and accuracy of conventional testing methods for evaluating AAM performance. One of the common concrete degradation mechanism in Quebec is the alkali-silica reaction. Many tests are available for evaluating aggregate reactivity. However, the accelerated mortar bar test is being used extensively due to its short testing duration. Therefore, this paper provides a review of the history of the mortar bar test, highlighting concerns about its feasibility for testing AAM.

A. Martinez, B. Fournier, A. Soliman, S. Diab
Civil Engineering History Overshadowed by Politics

Windsor, Ontario, boasts the busiest border crossing between Canada and the United States of America with over 40,000 people and $323 million worth of goods crossing the border daily. The vast majority of this traffic is facilitated by the Ambassador Bridge. Completed in 1929, the Ambassador Bridge for a short time had the longest span of any bridge in the world. While it is common for large infrastructure to become iconic symbols of cities and tourist destinations (e.g., Golden Gate Bridge in San Francisco, Brooklyn Bridge in New York), most residents of the Windsor area would shy away from selecting the bridge as a defining icon. In this paper, the history of the Ambassador Bridge is discussed ending with the current construction of the Gordie Howe International Bridge. The relationship between the owners and local community will be discussed. It is proposed that the political issues with the bridge have diminished the significance and engineering history of the bridge.

N. Bouzari, S. Ngabire, N. Van Engelen
Sustainable Basalt Reinforced Concrete Post

Basalt reinforced concrete to create a sustainable concrete post suitable for use in agricultural and livestock environments is one which has some merit. Basalt is an eco-friendly material originating from volcanic (igneous) rock. Basalt rebar is non-toxic and non-corrosive and will not wick moisture or conduct electricity. Concrete is an extremely brittle material that resists stresses while under compression, when reinforced with basalt (in the form of rebar), concrete is able to better withstand these tensile and shear stresses. Poles currently used in the Agri sector are either made of wood, pressure treated wood or steel reinforced concrete. Wood is subject to decay, and in the case of pressure treated wood exposure to chemical preservatives and leeching in to surrounding soil may cause contamination. If livestock eat the wood, they can be adversely affected. Available teel reinforced concrete posts have been observed to have experienced a significant amount of deformation that results in major cracks forming thereby exposing the steel reinforcement. These steel reinforced concrete posts are vulnerable to corrosion due other environmental factors such as rain, and freeze thaw cycles. Hence, using non-corrosive, green rebar (basalt) provides a superior alternative to the steel rebar currently being used. In this study, twelve (12) concrete posts with dimensions of:8 cm × 8 cm,10 cm × 10 cm and 14 cm × 14 cm; along with two (2) rebar configurations (one (1) rebar in the center of the post and four (4) rebars placed symmetrically at each corner) were tested to determine the optimal design, cost and desired strength for the proposed concrete pole.

J. Zohrehheydariha, A. Bastani, B. Paini, S. Das, D. Lawn
Parameters Affecting Selection of the Mitigation Strategies of Heat Island Effect

Urban Heat Island (UHI) effect can be a major concern due to its detrimental impacts on the society, the environment, and the economy. Several studies have presented different urban heat island mitigation strategies (UHIMSs) and their level of effectiveness. Some of the strategies discussed included greenery, cool material usage in construction, green roofs, and evaporative techniques; however, these approaches vary with respect to their levels of sustainability and resilience. A thorough review of the literature shows that there is a lack of a comprehensive system that considers the various parameters that play a significant role in qualifying the selected strategies as suitable candidates to mitigate the effects of the heat island. As such, this research aims at identifying, classifying, and organizing these parameters in a comprehensive framework with respect to two main criteria, which are sustainability and resilience. This paper presents the initial steps of developing this framework through the structuring of a comprehensive hierarchy for the heat island mitigation systems. Each level of the hierarchy provides further insights about the relative importance of the identified attributes/features of the mitigation strategies with respect to the sustainability and resilience aspects. Collectively, the hierarchy will provide the main skeleton for developing a comprehensive decision support system (DSS) for selecting the most suitable UHI mitigation strategy.

B. Bathaei, M. Abdel-Raheem
Assessment and Rehabilitation of a 50-Year Old Concrete Bridge Deck in Nackawic NB

With infrastructure across Canada continuing to age, Engineers are now more than ever seeing the need to perform comprehensive evaluations of existing structures. Such evaluations are crucial to accurately assess the condition of aging infrastructure and to design and implement the appropriate rehabilitation measures. The subject of this case study is a 50-year-old cable-stay bridge located in Nackawic NB; the structure is owned and operated by the New Brunswick Department of Transportation and Infrastructure (NBDTI) and has recently been selected to undergo a detailed structural evaluation. The bridge structure is two-lanes in width and spans approximately 85 m; the structure consists of an asphalt surfaced continuous concrete deck supported by steel girders and a single-tower cable-stay system. The focus of this article is on assessment and rehabilitation of the concrete bridge deck. A nondestructive testing program was developed and deployed, which involved: (1) a deterioration/delamination survey by use of ground penetrating radar (GPR), and (2) a half-cell potential survey to identify areas of probable corrosion. Nondestructive field inspections were complemented by laboratory testing of extracted core samples for determination of chloride ion content and compressive strength. Good correlation is observed between the two independent nondestructive field inspection techniques (GPR and half-cell potential), and problematic areas identified during nondestructive field inspections also yielded core samples having high chloride contents during laboratory testing. Based on the results of this detailed deck evaluation, recommendations for deck rehabilitation are developed and are scheduled for implementation during the summer of 2021.

C. Bryden, M. Bernard
Facility Design Standardization Work Process and Optimization in Capital Projects

While the construction industry always strives for better project performance, it has failed to achieve improved project performance in capital projects. To reap maximum benefits, the capital projects sector needs to better understand facility standardization, and its’ optimum implementation. By capturing the best practices for successful planning and execution of facility standardization, the achievement of a higher degree of facility standardization, and consequently, improved project performance is possible in capital projects. The purpose of this paper is to identify best practices, i.e., the key deliverables for standardization work process tasks, and the optimization strategy for facility standardization. To that extent, the researchers present the phase deliverables for the lifecycle of a standardized project, and outline the phases recommended for the execution of key tasks in a standardized project. Additionally, the paper investigates pertinent critical success factors (CSFs) for each work process key task, and identifies the optimization process of facility standardization. The paper also proposes a facility standardization optimization chart that serves as a visual representation of the work process. The researchers enlisted the support of the Construction Industry Institute (CII) research team (RT-UMM-01) to aid in identifying the deliverables for the work process key tasks, which were previously identified by RT-UMM-01. The researchers adopted a mixed-method methodology: a comprehensive literature review; an in-house survey amongst subject matter experts in the research team; and detailed discussions in virtual and in-person meetings. This study helps practitioners by providing standardization work process deliverables, and identifies CSFs for standardization projects’ lifecycles.

J. Choi, B. K. Shrestha, Y. H. Kwak, J. S. Shane
Performance and Ergonomic Characteristics of Expert Masons

Masons are aided by ergonomic inventions like tools, processes, and equipment, yet they are still subjected to performing physically demanding and hazardous tasks at the worksite. With advances in materials, design, and automation, the masonry work system may be modified to minimize the bodily harm associated with the industry. Analysis of the extensive motion data collected on masonry work enables us to understand the ergonomic risks of masonry tasks. Previous studies found that expert masons adopted ergonomically safer and more productive work methods than less experienced masons, as from analyzing the experts’ body kinematics and biomechanical force levels during masonry activities, we can provide training for a safer and more productive generation of masons. To achieve these goals, we investigated the expert masons’ work methods during four masonry activities to determine the associated risk. Specifically, eight expert masons with over 20 years of experience, laid out 16.6 kg concrete masonry units (CMUs) to construct (1) a standard wall, (2) a reinforced wall, (3) a wall in constraint space (under ceiling), and (4) a lead (first) course. Motion capture suits captured their motions, and a biomechanical analysis determined the load experienced by major body joints in each activity. The study found that the most critical body joints were in the lower back and upper limbs, as strain to these joints may lead to days away from work or, in severe cases, retirement. Furthermore, the results provided insights into expert masons’ distinctive work techniques through ergonomic evaluation for various masonry tasks.

J. Ryu, C. Haas, E. Abdel-Rahman
Fuzzy Art: Pattern Recognition of Wifi Detected Occupancy in Commercial Buildings

Research that predicts occupancy patterns in commercial buildings has gained in significance ever since the influence of occupants on building energy consumption became evident. Studies have employed a variety of sensory systems to collect the occupancy data and understand human behaviors throughout buildings. However, establishing a dedicated sensor network to collect occupancy data can become expensive for building owners. In this context, obtaining occupancy data from an existing WiFi network could eliminate the cost concerns. Data within the WiFi routers provide sufficient information for accurate estimates of occupancy. To estimate occupancy levels, this work proposes to learn and recognize WiFi connection using an Adaptive Resonance Theory (ART) artificial neural network. A detailed understanding of occupancy patterns using the WiFi data is helpful for developing heating and cooling schedules that optimize HVAC energy consumption. For this study, occupancy data was collected over a 17-week semester at the University of New Mexico using existing WiFi routers located in a large lecture hall used by multiple classes. This data was used to learn patterns of repetition using the neural network. The results show that if the 24-h occupancy profiles can be subdivided into smaller time segments defined by external schedules such as lecture start and end times or other constraints, significant patterns can be detected. A detailed understanding of these patterns can greatly facilitate occupancy load forecasting for effective building management (e.g. HVAC operation).

Krishna Chaitanya Jagadeesh Simma, Thomas P. Caudell, Susan M. Bogus, Andrea Mammoli
Field Performance Evaluation of Asphalt Mixes at Approach Intersections: A Municipal Perspective

Asphalt concrete is among the materials which are most widely used for roads and airport pavements. These pavements over time suffer failure due to passing traffic loads and exposure to different environmental conditions. Typically, when designing a road at the project level, a homogenous pavement design is considered for the entire road segment meaning similar pavement materials and thicknesses are applied throughout a road segment. However, locations such as approach intersections undergo different loading scenarios which make these areas more vulnerable to pavement premature failures such as pavement permanent deformation/rutting and shoving during its service life. The difference in loading scenario is due to high shear stresses associated with vehicle’s stopping and accelerating and also slow traffic movement. As a result, sections such as approach intersections required more frequent treatments for addressing the pavement distresses which makes it both costly and time consuming. Annually, millions of dollars have been spent to compensate rutting failures in the pavement. Therefore, it is critical to agencies to select proper asphalt mixes such as high-performance asphalt mixes for the approach intersections to ensure adequate durability, quality, and safety. The proper mixes also save time and money and minimize environmental impact throughout the road’s lifecycle.With more people coming to York Region’s community every year, the number of vehicles and percentage of trucks transporting goods and services has increased significantly. Therefore, with an increase in temperature pattern in recent years in addition to this traffic increase, York Region is experiencing premature pavement failure, commonly rutting and some shoving, at some of its high-volume intersections. To study the in-service performance and root cause of the rutting and other distress at York Region’s approach intersection, six (6) approach intersections are selected for this study. The study consists of conducting rut depth measurement and geotechnical investigation such as ground generation radar (GPR) testing and collecting cores and borehole samples on the selected sites. This paper presents the field investigation results along with ranking methods to compare the susceptibility of the asphalt surface layer mix to rutting for the tested locations. This paper also explores ideas on how to extrapolate this project level information to the network level for the asset management purposes.

M. Kafi Farashah, S. Varamini, S. Tighe
Measuring Key Parameters Governing Anion Transport Through Mx-80 Bentonite

The Nuclear Waste Management Organization (NWMO) is responsible for the design and implementation of Canada’s deep geological repository (DGR), which will be constructed ~ 500 m below ground surface to safely contain and isolate used nuclear fuel. Used fuel containers (UFC), designed by NWMO as part of multi-barrier system for DGR, comprises of an inner steel core with an outer copper layer that serves as a corrosion barrier. Surrounding the UFC, a highly compacted MX-80 bentonite (HCB) is used to suppress the transport of corrosive agents to the UFC and to limit the movement of radionuclides out of the DGR, in the highly unlikely event of a UFC failure. Under anaerobic conditions, sulfate-reducing bacteria at the interface of the host rock and bentonite may produce bisulfide (HS−) that can transport to the UFC surface and corrode the copper barrier. Therefore, it is crucial to understand HS− transport mechanisms through bentonite to assess the long-term DGR performance. Due to bentonite’s low permeability, HS− transport will be diffusion-driven; therefore, the apparent diffusion coefficient and retardation are critical parameters for the DGR performance assessment. This study aims to quantify HS− diffusion through bentonite using diffusion experiments under a range of anticipated DGR conditions (e.g., temperature, ionic concentration). This paper outlines the underpinning theory, experimental methodology developed to conduct experiments, and preliminary results. Altogether, this work bolsters confidence in the experimental design and methodology that will be used to determine necessary key parameters to model reactive transport of HS− through the DGR’s bentonite barrier.

F. Chowdhury, T. L. Rashwan, S. A. Papry, M. Behazin, P. G. Keech, P. Mondal, J. Sharma, M. Krol
Piers Type and Height Effect on Bridges Fragilities

Bridges play an essential role in rescue operations in the case of strong earthquakes. Thus, it’s vital to prevent these structures from damages during these events. The study of bridges fragility under earthquakes is a big challenge of scientists. Besides the seismic parameters, both structural system and geometric properties significantly affect the bridge fragility. In this aspect, the present work aims at studying the effect of the piers type and height on the seismic behaviour of reinforced concrete bridges. For this purpose, non-linear dynamic analyses were carried out on two multi-span continuous girder bridges models subjected to seismic excitations varying from weak to strong. The type and the height of piers were varied; the first bridge model is supported by multiple columns bent and the second by wall piers. In order to highlight the effect of the aforementioned parameters on bridges models fragilities, fragility curves were drawn for the various models where a comparative study was elaborated on the basis of top piers displacements.

K. Zellat, M. C. Djemai, M. Bensaibi
Boardwalks the Bridges to Nature

To the average recreational user of trails, boardwalks provide the means to access the surrounding landscape and maximise the natural experience. To the owner of the asset, these are pieces of infrastructure that need to be maintained for user safety, provide transit for light vehicles & pedestrians whilst adopting a comfortable amount of risk to provide the natural experience for users. The design engineer not only has to address these requests from the owner, but they also must provide; Elegant & non-intrusive geometry for a natural user experience; safe and compatible timber treatments for the user and environment and be constructible low maintenance durable structures.

Rowan Shields
Optimizing Green Roof Design Parameters and Their Effects on Thermal Performance Under Current and Future Climates in the City of Toronto

Buildings contribute 30% of total energy consumption worldwide and account for 28% of CO2 emissions. Green roofs (GRs) have shown potential in reducing cooling and heating loads of buildings, and thus, the related carbon emissions. The objective of this research was to analyze the thermal performance of extensive GRs and find suitable GR designs that reduce both cooling and heating building loads under both current and future climates in the City of Toronto. The effect of two design parameters, GR growing media depth and the insulation thickness of the roof, on building energy consumption were investigated. EnergyPlus was used to model GR energy balance for a secondary school building, the total energy consumption and the heating and cooling loads. Due to Toronto being a heating-dominated city, the use of insulated GR with a growing media depth of 200 mm was effective in reducing building total energy consumption. However, results showed that for insulation thicknesses of more than 120 mm under current climate and 80 mm under future climate, the total energy consumption of GRs increased compared to a reference (conventional) roof without GR. Therefore, use of highly insulated extensive GRs to? reduce building total energy consumption is not a suitable replacement for insulated conventional roof for secondary schools in the City of Toronto under current and future climates. Nonetheless, use of uninsulated extensive GRs are suitable choice in reducing the total energy consumption for retrofit schools with poorly insulated conventional roofs.

B. Yousefi Pihani, M. M. Krol, U. T. Khan
Life Cycle GHG Emissions Analysis of Building-Level Carbon-Capturing Technologies

The building sector contributes 12% of the greenhouse gas (GHG) emissions in Canada. Building heating is the main contributor to building-level GHG emissions, primarily due to natural gas combustion. Although carbon-capturing is an emerging technology used to curb the GHG emissions in the fossil fuel-based power generation sector, the possibility of implementing this technology in natural gas building heating systems has not been comprehensively explored. This paper aims to evaluate the life cycle GHG emission reduction potential of integrating carbon capturing systems in residential and commercial building heating systems. The GHG emission reduction potential of commercially available building level carbon-capturing system (which uses Potassium Hydroxide (KOH) to capture CO2 and generate Potassium Carbonate as a by-product) and a carbon-capturing technology used in fossil fuel power generation plants (which uses Mono Ethanol Amine (MEA) based chemical absorption to separate CO2) were compared. Life cycle GHG assessment was conducted using TRACI 2.0 impact assessment method. The percentage reduction of life cycle GHG emissions was lower than the operational GHG emission reduction in MEA based systems due to the embodied emissions associated with the carbon-capturing process life cycle. The KOH-based system also consists of a substantial amount of embodied GHG emissions. However, the life cycle GHG emissions reduction of the KOH-based system was higher than the GHG emissions reduced during the operation when avoided emissions of the by-products were accounted. The findings of this paper will assist building owners, community developers, and policymakers in assessing the feasibility of implementing building-level carbon-capturing in the future.

Don Rukmal Liyanage, Kasun Hewage, Hirushie Karunathilake, Rehan Sadiq
Urban Resilience Design Strategies

As engineers, how can we better design for resilience? This research sets out to compile a comprehensive set of urban resilience design strategies, where “resilience” is defined as the “capability of dealing with future shocks and stresses and continuing to function.” Resilience concepts collected from two literature reviews are integrated to produce a set of 60 resilience design strategies, organized into a three-part design aid based on whether they improve core, specified, or general resilience. The design aid can be used to assess the existing resilience of an urban area, find ways to improve its resilience, or to analyse a past catastrophe. To trial its use, the design aid was applied to a proposed neighbourhood in London, Ontario, which led to a refinement in the aid and generated many ideas on how to improve the neighbourhood’s resilience. The aid offers a straightforward and holistic tool for designing for resilience.

M. Uda, C. Kennedy
Exploring Computing Time for Automatic Occlusion Detection: A Scan-Based Algorithm Versus a Geometry-Based Algorithm

Research shows Virtual Reality (VR) can facilitate design review and coordination tasks in the construction industry. However, visualizing occluded objects in a VR environment is still challenging. Both geometry-based algorithms and scan-based algorithms showed potential in automatically detect occluded objects in 3D models. This paper created both algorithms and explored the key factors for the overall computing time. Results show that both algorithms can perform the occlusion detection task for a Building Information Model with 5387 objects in three hours. The number of occluded objects showed a significant impact on the computing time of the geometry-based algorithm, while the computing time of the scan-based algorithm was more influenced by the number of objects and the granularity of virtual scans of the model. This paper contributes to the body of knowledge by developing the two algorithms and measuring the performance of every activity in their workflows. The results can support the future development and optimization of automatic occlusion detection algorithms for VR applications in the construction industry.

B. Han, F. Leite
Review of Infrastructure Resiliency Policy for Natural Disasters

The growing financial impact of natural disasters has motivated governments to rethink resiliency policy pertaining to built-infrastructure. The creation of an effective resiliency policy is a product of the interplay between informed elites (i.e., engineers, utility operators), governments, and citizen engagement. To help orientate informed elites on the prevalent trends and constraints in this policy domain, a literature review was conducted on built-infrastructure resiliency policy addressing natural disasters. Collection methodology consisted of a targeted keyword search on JSTOR, which resulted in forty relevant articles. Those articles were categorized into the following five resiliency policy approaches: mitigation, adaptation, economic, reconstruction, and policy frameworks. Additionally, a review of country-specific disaster response frameworks was also conducted. The review highlights recent trends in policy decisions. Decision-making on infrastructure resilience policy is moving from a national level to a local level. The consequences of that jurisdictional movement have caused policy decisions to favor mitigation and education tactics which prove to be more politically and fiscally feasible than adaptation tactics. The review also revealed a gap in the literature concerning the diversity of natural disasters being studied. A clear focus has been placed on earthquakes and flooding while wildfires and drought have been neglected.

A. Colletta, J. Lim, J. Choi
Towards a Visitable Housing Policy in Fredericton

“VisitAble housing” employs three main design features in newly built homes: a zero-step entryway; 32″ (813 mm) wide doorways and hallways; and an accessible bathroom. The goal of this project was to explore the potential for a VisitAble housing policy in Fredericton; a promising concept, but has had limited uptake in Canada. Statistics Canada data show that New Brunswick (NB) has among the highest disability rates in Canada (23%), but has the lowest rate of individuals living in a home with an accessible entrance (17%). Google Maps Street View and GeoNB were used to determine the number of zero step and ramped entrances to single-family and garden homes (as a proxy for VisitAbility) among a sample of 6 of 25 residential Dissemination Areas (DA) in Fredericton. There were 34 of 1447 homes (2.3%) that had an accessible entrance. A survey was distributed to nine Fredericton-area home builders (n = 4 responses) asking about the prevalence, demand, and the feasibility of VisitAble housing in the Fredericton house building industry. While a very small sample, the consistency of builder responses suggest they are building homes with accessible features at a rate commensurate with their interpretation of the demand and have concerns similar to those expressed in previous CMHC research. Low rates of accessible home entrances in NB suggest other provinces are more effective in the development of strategies that result in an outcome of more accessible homes. Opportunities exist to explore more prescriptive policy solutions to support VisitAble home development in NB.

M. Gray, T. Hanson
Design and Installation of UHPC H-Piles at the Lily River Detour Bridge, Highway 11, Near Kapuskasing, Ontario, Canada

Through a Change Proposal, Facca Incorporated was approved by the Ontario Ministry of Transportation (MTO) to replace the as-tendered steel H-piles by the UHPC piles for supporting the west abutment of the Lily River Detour Bridge. Using the H-shaped UHPC pile developed and tested at Iowa State University in 2008 as the basis, 300 mm deep Dura UHPC piles were designed, fabricated, and successfully installed for the Lily River Detour Bridge. This paper will provide details of the innovative design of the piles, pile fabrication process and the field testing of full-length piles. The presentation will also cover details about driving these first ever UHPC piles in Canada and the challenging soils conditions encountered in this process.

P. Loh, E. Booya, D. Gardonio
Rrenewable Natural Gas as a Greener Energy Source: A Life Cycle Cost–Benefit Analysis

Natural gas (NG) supplies approximately one-third of Canada’s electricity and heating demand. Even though it is a cleaner form of energy compared to other fossil fuels, it still contributes to greenhouse gas emissions. Therefore, rigorous actions are required to further reduce the NG-related emissions. Renewable natural gas (RNG) is a greener option compared to conventional NG. It possesses an untapped potential in energy generation applications. However, a comprehensive analysis is required to determine the incremental benefits and costs of replacing conventional NG with RNG in the main carbon-intensive applications of the energy sector. Moreover, while greener interventions provide operational environmental benefits, they may carry added life cycle impacts during fuel production, transmission, and end-of-life stages. Therefore, life cycle thinking is essential in assessing the exact costs and benefits. This study conducted scenario-based life cycle environmental and economic assessments to determine the costs and benefits of replacing the conventional NG system with RNG and other alternative residential building heating systems. The assessment was further extended to assess the suitability of replacing NG with RNG-based and other building heating systems in Canadian provinces that rely heavily on NG to discuss the effect of regional parameters on decisions related to building energy infrastructure. The findings of this study are geared towards enabling decision-makers and investors to gain a more holistic view of investment decisions related to green energy initiatives in building energy infrastructure.

R. Kotagodahetti, K. Hewage, H. Karunathilake, R. Sadiq
Effects of Shape and Reinforcement Details of UHPC Shear Key on the Performance of Adjacent Prestressed Concrete Box Beam Bridges

Adjacent precast prestressed concrete box beam bridges have often been preferred for medium to short span bridges in North America due to ease and speed of construction, and relatively low cost. However, longitudinal cracks in the shear keys have been identified as a recurring issue during their service life. In recent years, ultra-high-performance concrete (UHPC) has been used as filling material in the shear keys of adjacent box beam bridges due to its superior mechanical and bond properties. UHPC has outstanding bond with reinforcement, which allows shorter reinforcement embedment length. In the United States, fourteen adjacent box beam bridges with UHPC shear key connections have been completed between 2014 and 2018. In Canada, fifty-five adjacent box beam bridges with UHPC shear keys have been completed between 2007 and 2018. However, the UHPC shear key geometry and reinforcement details used in the United States (U-SK) are quite different from the once used in Canada (C-SK). No analytical, experimental or field studies have been conducted to compare the long-term performance of the two shear key types. This research investigates the two shear key types under traffic load and temperature effects. All the box beam bridges in the US used the same UHPC shear key details, while in Canada, there is no consensus which detail to use in bridges built in different provinces. Therefore, the C-SK shear key details that were found in available literature were used in this study. A finite element (FE) model was developed, then calibrated and validated based on the field test results from the first adjacent box beam girder bridge in the United States utilizing UHPC shear key connections. After validation, the model was used to investigate the effects of the shear key shape and reinforcement details on the bridge performance. The results indicate that U-SK generally experienced better performance in terms of stresses and interface bond degradation compared to the C-SK.

Ali A. Semendary, Eric Steinberg, Dagmar Svecova
Classroom Space Layout for Responding to Occupants’ Health Concerns and Flexible Space Utilization

During COVID-19, the importance of reconfiguring indoor space layout has received attention. In particular, space layout in school buildings should keep a safe distance among people to protect occupants’ health while satisfying requirements for space utilization purposes to ensure learning experience. However, space constraints and conditions such as room size, boundary, and door locations, etc. make it difficult to adapt space layout required for diverse learning experiences. In this respect, this research aims to apply a space planning framework using Building Information Modeling (BIM) that can streamline the process of reconfiguring space layout. The research outcomes contribute to decision-making of space layouts for providing suitable indoor environments under emergency situations beyond the current pandemic. Although the space planning method has helped with optimizing different space types within a building, it has not expanded its usability within a single space due to lack of understanding inter-relationships of multiple constituent elements within a space. In this respect, this research addresses the constraints of elements within a space to respond to an emerging issue of flexible space reconfiguration for protecting occupants’ health and learning experience. This research broadens applications of the space planning method to responsive and resilient space management by integrating it with BIM in the architectural, engineering, and construction (AEC) industry.

Soowon Chang, Malav Haresh Doshi
New Methodology for Efficient Management of Chloramine Concentrations in Stormwater Systems

Polluted urban stormwater effluents pose risks to receiving watercourses. Many municipalities have concerns about point-source releases of chloramine-treated drinking water that reach the drainage system through outdoor and industrial water uses. Since chloramine decay coefficients vary temporally and spatially, no available stormwater model can simulate them accurately. Therefore, a novel stormwater quality model (VDCS) is introduced to simulate chloramine decay. The model considers the variability of chloramine decay using three decay settings, as defined by the user: constant, land-use specific, and temporally and spatially-varying decay coefficients. The model was validated using the results of field sampling and MIKE URBAN simulations. Variable chloramine decay coefficients generated 67% and 100% higher concentrations than the constant decay coefficient. A new approach to develop water quality maps was introduced that shows the levels of chloramine at the system outlet as a result of point-source releases occurring anywhere in the stormwater system. The VDCS model along with MIKE URBAN and Arc-GIS were used to develop chloramine concentration maps for a case study stormwater basin in Edmonton. A practical fire hydrant discharge of 1.0 m3/s was used as a reference case under different dry and wet weather conditions. The Bayesian Kriging Method was used to generate the water quality maps using outputs of the stormwater hydraulic and quality models. For dry weather flows, results showed that chloramine concentrations were above limits over the entire basin, and only a design storm of a 10-year return period produced chloramine concentrations below regulation discharge limits. Overall, concentration maps provide a stand-alone tool that can help system operators to manage stormwater pollution without performing time- and labour-intensive simulations.

Mohamed Gaafar, Evan G. R. Davies
Proceedings of the Canadian Society of Civil Engineering Annual Conference 2021
herausgegeben von
Scott Walbridge
Mazdak Nik-Bakht
Kelvin Tsun Wai Ng
Manas Shome
M. Shahria Alam
Ashraf el Damatty
Gordon Lovegrove
Springer Nature Singapore
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