Recent Developments in Structural Engineering, Volume 3

Inhaltsverzeichnis

1. Numerical Analysis of Honeycomb Core Sandwich Panel Under Blast Loading

   Nikhil Ghate, Manmohan Dass Goel

   Abstract

   In recent years, the metallic sandwich panels especially with honeycomb core showed immense potential in blast load mitigation application due to their lightweight characteristics along with excellent energy absorption under impulsive loading. In this study, comprehensive investigation on dynamic behaviour of sandwich panel consisting of multilayers of honeycomb core has been conducted by means of numerical simulation. Here, the sandwich panel of honeycomb core having hexagonal topology is simulated numerically using LS-DYNA^®. This study investigated the influence of multi-layered core on the blast performance of sandwich panel. Base on this study, it can be concluded that the multilayers of core with intermediate sheets enhance sandwich panel performance and enable the application of larger loads for the same configuration under blast loading.

2. CFRP—A Boon to Retrofitting Industry

   Neelima Varma, Swati Ajay Kulkarni, Gopal Rai

   Abstract

   Carbon fiber-reinforced polymer (CFRP) wrapping is one of the major methods for repair and rehabilitation of concrete structures. CFRP laminates are new carbon-based composite materials that are applied externally to deteriorated concrete bridges. Due to its lightweight, high tensile strength and also long-term durability, CFRP has proved to be a major material for retrofitting. This high strength materials improve the various structural properties such as flexure strength, shear strength, deflection, vibrations and stiffness of various bridge components.

3. Assessment of Different Curing Methods on Marble Dust Concrete

   Nikhil agrawal, Anshuman Srivastava, Manpreet Singh, Rajendra Khapre

   Abstract

   This research deals with significance of marble dust containing concrete by using different curing methods on it. Marble dust is used as a partial replacement of cement ranging from 0 to 15% by cement weights were considered in concrete. The most important aim of this study to reveal effectiv method of curing which gives better mechanical and durability properties like compressive strength and durability property of marble dust incorporated concrete. These experimental studies analyze the three different curing methods and assessment of the compressive strength, and also the variation of marble dust replacement percentage with cement is also taken into experimentation.

4. Building Materials for Repair and Strengthening of Monuments: A Review

   P. K. V. R. Padalu, R. Vashisht

   Abstract

   Monuments were built for thousands of years as the most enduring and well-known representations of past civilizations. It is crucial to preserve them, because they are national symbols with unique cultural and historical significance. The deterioration of the structures happens as a result of weathering, fire, natural disasters like earthquakes, construction flaws, and numerous other factors. In general, the issue with repairing and reinforcing regular buildings is very different from the issue with restoring monument buildings. The goal of keeping a monumental structure in use may be viewed as secondary in importance and any event as a result of the effort made to fulfil the main task. In the case of monumental buildings, emphasis is placed on the preservation of their aesthetic and historical aspects. Therefore, the restoration strives to protect and highlight the monument’s or building’s aesthetic and historical aspects. The choice of appropriate material for the restoration depends on the appearance of the original structure. New materials must be compatible with those already used in the building. The goal of the present study is to provide an overview of the materials used to restore the structural integrity of historic structures and monuments that have been damaged by seismic activity. All of these buildings need extra attention because of their unique historical or architectural value, or because they are significant because they are still standing examples of a former way of life.

5. Computational Modeling of RC S-Curved Bridge Using Finite Element Approach

   Swaroop S. Patil, Vikram S. Singh, Keshav K. Sangle

   Abstract

   A bridge is a structure that helps in connecting two inaccessible places due to obstacles such as a river, deep valleys, and other large water bodies, but some obstructions such as site restrictions, alignment of the bridge, increased traffic, urbanization, and a change in speed limit which may change bridge alignment to curve path. Many factors which influence bridge design are bridge usage or functionality, anchorage, terrain and topography, economy, and aesthetic appearance of where the bridge will be built. The primary goal of bridge analysis is to determine the shear force, bending moments, torsional moments, and deformation caused by various loads given by IRC specifications. This can be achieved by analyzing the bridge model using finite element method-based software which will help correlate the structural behavior with the actual structure. To understand how the S-curved bridge behaves under IRC-specified loading, a detailed investigation needs to be done. This can be achieved by reviewing the literature, case studies, and analysis of existing curved bridge girders using a numerical model. This paper will be focusing on a comparative study of RC S-curved bridge girders having a certain cross-section and span using the finite element method-based numerical model.

6. Effect of Multiple Earthquakes on Force Based and Capacity Based Designed Structures

   Pavan Kumar Thippa, R. K. Tripathi, Govardhan Bhat

   Abstract

   Earthquakes are natural phenomena resulting in damage of structures and loss of life. In this study structure is designed using two design philosophies Forced Based Design (FBD) and Capacity Based Design (CBD). In many parts of the world the repeated earthquakes are noticed, which resulted in collapse of damaged structures due to first earthquake. The study on damaged structure is significant for developing nations which gives an understanding of existing structure designed with code based spectrum. Seismic codes across the world design the structures for a single earthquake, multiple earthquakes are not considered. Incremental Dynamic Analysis (IDA) is performed to assess the structure behavior under single and multiple earthquakes up to collapse for two designed structures. The structure response is studied in terms of plastic hinge formation, storey drift and roof displacement. In comparison to single earthquakes multiple earthquake are significant. It is also observed that capacity based designed structure performed well under single and multiple earthquakes.

7. Effect of Metakaolin on Self-healing Concrete with and Without Fly Ash Aggregates

   Rama Mohan Rao Pannem, Bhaskar Bashaveni

   Abstract

   The present work is mainly focused on the effect of metakaolin on the self-healing and mechanical properties of conventional and lightweight concrete. The combined effect of autogenous and autonomous healing on mechanical and healing mechanisms was determined by the partial replacement of Coarse aggregate by Fly Ash Aggregates. Bacillus Subtillus bacteria was used in this experimental work along with its nutrients. In conventional concrete, 30% of coarse aggregates were replaced by fly ash aggregates and used as lightweight concrete. In these two types of concrete mixes, metakaolin is used as the partial replacement of the cement by 10, 15, and 20% by binder content. Cylindrical specimens were used to test the split tensile strength and healing mechanism and cube specimens were used for compressive strength at the age of 28 days curing. From the test results, it is clear that the 15% replacement of cement by metakaolin showed better performance and satisfactory strength recovery. FESEM and EDS tests were performed on precipitation collected from conventional and lightweight concrete mixes. FESEM and EDS results are clear that the precipitation is in calcite form.

8. Measuring Localized Strains and Capturing Fatigue Crack Initiation Event Using Digital Image Correlation Technique

   Shreebanta Kumar Jena, Punit Arora, Suneel K. Gupta, J. Chattopadhyay

   Abstract

   The present study focuses on application of Digital Image Correlation technique (DIC) to low cycle fatigue testing for localized strain measurement and capturing crack initiation event at relatively lower value of strain amplitude. Low cycle fatigue tests have been conducted on unnotched as well as notched tube specimen under different cyclic loading conditions. The validation exercise of the DIC systems has been carried out by conducting tests on unnotched tube specimens subjected to completely reversible loading under extensometer-controlled condition. This is followed by conducting strain-controlled test on notched tube specimen with a single sided through thickness transverse hole in the gauge region of the tube and subjected to remote cyclic axial and torsional loading conditions. During the test, measurement of the localized strain field information as well as capturing the crack initiation event at/ahead of notch have also been carried out on the outer surface of the tube specimen. Further, the applicability of the DIC measurement technique for curved geometry under such low strain amplitude and complex loading scenario has been evaluated by comparing the DIC measurements with their corresponding strain gauge measurements. DIC measurements are in good agreement with the strain gauge results.

9. Investigation of Residual Strength of RC Column Subjected to Blast Loading

   Md.Muslim Ansari, Ajay Chourasia

   Abstract

   This paper presents the behavior of reinforced concrete column subjected to varied intensity of blast load. A simplified 3D numerical model has been presented to show the load carrying capacity or residual strength of RC column under imposed load and encounter a blast load. With varied intensity of imposed load, the behaviour of RC column and residual strength variation has been investigated, wherein, different imposed load to column resembles the storey level. After the validation of numerical model with experimental results, damage pattern and residual strength of RC column has been discussed in detail with varied standoff distance (500–2000 mm) and weight of TNT explosive from 5 to 25 kg.

10. Response Prediction of Buried Steel Pipeline Under Different Blast Scenarios with Advanced 3D Coupled Eulerian–Lagrangian Finite-Element (CEL-FE) Approach

    S. M. Anas, Rafat Tahzeeb, Mehtab Alam, Mohd Shariq

    Abstract

    Pipelines carrying lifeline commodities are required to protect them from damage/theft and therefore buried. With the rising frequency of industrial accidents and intentional sabotage in high-risk areas, protecting these critical infrastructures is vital to ensuring national security and resource availability. Such underground components during their service life may be subjected to high-intensity impulsive loads induced by industrial explosions and subversive blasts which could be on or below the surface and vehicle blasts above the buried pipeline. For the perpetual supply of lifeline commodities, the safety of the buried pipeline is of great concern against their vulnerability to blast loading. In this article, high-fidelity numerical analyses are done to simulate explosion on a buried steel pipeline using an advanced 3D CEL-FE method. For this purpose, a numerical model consisting of five different parts namely; air, soil, TNT, steel pipe, and Eulerian domain, is created in the Abaqus programming tool and its investigation has been carried out under different explosion scenarios concerning different locations of the explosive charge. The pipe material used is high-strength carbon steel, specifically grade X65. This type of steel has a static yield strength of 500 MPa and a dynamic strength of 625 MPa. It has an outer diameter of 1000 mm, a thickness of 10 mm, and an overall length of 12,000 mm. These dimensions align with standard pipeline designs used for high-capacity transmission, making the study results relevant to real-world applications. The pipeline is assumed seamless and empty and is buried in the soil medium (brown clayey) at a depth of 2000 mm below ground level. The Eulerian domain considered is a cube having a size of 12,000 mm, half part of which is located with air and half with the soil using a volume fraction tool. Simplified Johnson–Cook plasticity (JCP), Jones-Wilkins-Lee(JWL)-Equation-of-State(EOS), ideal gas EOS, and Mohr–Coulomb plasticity (MCP) constitutive models, respectively, have been selected for defining the behavior of steel, TNT, air, and soil medium. These material models, widely recognized for their predictive accuracy, capture the complex behavior under extreme loading conditions. Responses are compared and discussed. Johnson–Cook damage analysis shows that subsurface explosion is detrimental to the buried pipeline while partial subsurface, surface, and free-air explosions cause the damage much less than the subsurface explosion and with descending order of the degree of damage to the pipeline. The results highlight the urgent need for the development of advanced blast-resistant pipeline designs, integrating state-of-the-art numerical modeling techniques to assess and mitigate real-world explosive risks with higher precision. These findings are pivotal for advancing pipeline resilience standards, influencing policy frameworks, and driving the creation of robust, adaptive protection strategies that effectively safeguard critical infrastructure from diverse explosive threats in both military and civilian contexts.

11. Time History Analysis of Balanced Cantilever Bridge “A Case Study”

    Sneha B. Bahirgonde, Avinash S. Joshi

    Abstract

    Time history analysis is a method used in structural engineering to simulate the behavior of a structure under dynamic loads over time. It is particularly useful for balanced cantilever bridges with distances greater than 150 m between expansion joints. The results can provide valuable insights into the structure’s behavior under dynamic loads, helping engineers optimize design and ensure it can withstand future loads. This study aims to develop a model for a balanced cantilever bridge in MIDAS Civil and explore its non-linear behavior using time history analysis for seismic forces. The results show that displacements in the longitudinal direction are higher than in the transverse direction in both NLTHA and ERSM. The maximum displacement at the pier top end for the El-Centro 1940 earthquake was about 90% more than those obtained by ERSM analysis. The nonlinear time history analysis also shows a 60% higher torsional response than the Elastic response spectrum method.

12. Study of Seismic and Wind Effect on Multi-storied Building with and Without Resisting Systems

    Deenay Ambade, Nidhi Gosavi, Vaishali Mendhe

    Abstract

    The construction of the multistoried buildings became unavoidable due to the population explosion and land scarcity. These multistoried buildings are subjected to lateral loads such as wind load and earthquake load. Thus, the safety and stability of the building become important. Wind and earthquakes are horizontal loads on structures, creating vibrations in the walls, floors, columns, and the connectors that connect them. The difference in movement between the top and bottom of the building exerts stresses, it can also induce torsion, which can cause the structure to fail; therefore, it is essential to study these horizontal forces during the design process. In this study, the seismic and wind analysis for the G + 14 storey building is carried out for the different resisting systems such as bracings and shear walls by using staad.pro software. For seismic and wind evaluation, IS 1893 (Part 1): 2016 and IS 875 (Part 3): 2015 are used. This study provides information about the variation in the base shear, storey drift, and storey displacement with the change in the resisting system in the different seismic zones and terrain categories. This study reveals that the shear wall at the centre of the building is more efficient than the other resisting systems in different seismic zones and terrain categories.

13. Correction to: A Study on the Hysteretic Behaviour of Combined Metallic Yielding Dampers Under Cyclic Load Using Finite Element Software

    Bajrabahu D. N. Deo, Sanjeev Kumar, Romanbabu M. Oinam