Faculty Publications
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Item Numerical study on the behavior of RC beams by using GFRP bars as an alternate to steel bars(Elsevier Ltd, 2023) Kuttagola, I.; Prashanth, M.H.; Kumar, A.The numerical study of the behavior of reinforced concrete beams by using Glass fiber reinforced polymer (GFRP) bars as an alternate to steel bars has been explored in this research. The numerical modelling of the beams is done using Finite element analysis (FEA) software ABAQUS. In the present study the beam with Glass fiber reinforced polymer (GFRP) bars as both longitudinal & transverse reinforcement is compared with conventional reinforced concrete beam. The numerical simulation is performed for three-point bending for displacement control. The results of load, strain and deflection data has been obtained from the numerical modelling. Stress versus strain curves, load versus strain curves and load versus deflection curves are plotted using the output data. The displacement, strain developed in longitudinal bars and stirrups, load carrying capacity, energy absorbed are then calculated using the data and are compared. From the results, it is observed that the Glass fiber reinforced polymer (GFRP) reinforced concrete beams have load carrying capacity par with conventional reinforced concrete beam. Further, Glass fiber reinforced polymer (GFRP) reinforced concrete beams have higher yield strains and experienced more energy absorption over conventional reinforced concrete beam. © 2023 Elsevier Ltd. All rights reserved.Item Numerical Analysis on Fatigue Behavior of Plain Concrete and Alkali-activated Concrete(Institute of Physics, 2024) Sushanthkumar, K.V.; Channappa, T.M.; Prashanth, M.H.; Chaitra, A.R.Alkali-activated concrete (AAC) has recently gained a lot of potential to become one of the most recommended sustainable replacements for Ordinary Portland cement concrete (OPCC). In the present investigation, an attempt has been made to study the static and fatigue flexural behavior of AAC compared to that of OPCC by using numerical modeling FEA software, ABAQUS. The nonlinear behavior of the stress-strain curve of the concrete has been studied using the concrete damage plasticity (CDP) model. A 2D notched beam was modelled using plane stress condition and three-point bending tests were performed under monotonic loading to obtain the static behavior of concrete. The result obtained has been utilized to fix the loading range for cyclic loads in fatigue analysis and at different loading frequencies. The load-CMOD curves and load-deflection curves were obtained for both static and fatigue loading, and the number of cycles to failure during fatigue. From the results, it has been observed that the Ordinary Portland cement concrete specimens sustain more load than that of Alkali-activated concrete under monotonic loading. However, AAC has shown more resistance to fatigue than that of the OPCC and the frequency of loading significantly influences the fatigue performance. © Published under licence by IOP Publishing Ltd.Item Performance Evaluation of Stone Column Reinforced Shedi Soil(Springer Science and Business Media Deutschland GmbH, 2024) Vibhoosha, M.P.; Bhasi, A.; Nayak, S.Ground modification techniques are adequate in the present scenario, due to the scarcity of suitable construction sites. The problematic soil widespread in the Konkan region of west coast India is shedi soil. Construction over this soil is challenging because it loses strength when saturated. Among the various ground modification techniques, the use of stone columns is an ideal technique due to their higher strength and stiffness properties compared to the surrounding soft soil. The cost effectiveness and ease of installation make stone column method popular in India. In the present paper, the performance of stone column reinforced shedi soil is analysed, by developing a three-dimensional finite element model in ABAQUS. The long-term stability is imparted with the time-dependent behaviour and it is evaluated. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.Item Comparative study of damage behavior of synthetic and natural ber-reinforced brittle composite and natural ber-reinforced exible composite subjected to low-velocity impact(Sharif University of Technology, 2020) Mahesh, V.; Joladarashi, S.; Kulkarni, S.M.In the present study, a comparative study of the damage behavior of Glass-Epoxy (GE), Jute-Epoxy (JE) laminates with [0=90]s orientation, and Jute-Rubber-Jute (JRJ) sandwich is carried out by ABAQUS/CAE nite element software. The GE, JE laminate, and JRJ sandwich with a thickness rate of 2 mm are impacted by a hemispherical-shaped impactor at a velocity of 2.5 m/s. The mechanisms by which the brittle laminate gets damaged are analyzed in accordance with Hashin's 2D failure criterion, and exible composites are analyzed by the ductile damage mechanism. The absorbed energy and the incipient point of each laminate were compared. According to the results, there was no evidence of delamination in JRJ as opposed to GE and JE. The compliant nature of a rubber plays a role in absorbing more energy, which is slightly higher than the energy absorbed in GE. Moreover, it was observed that there was no incipient point in JRJ sandwich, meaning that there was no cracking of matrix since the rubber was elastic material. Thus, the JRJ material can be a better substitute for GE laminate in low-velocity applications. The procedure proposed for the analysis in the present study can serve as a benchmark method for modeling the impact behavior of composite structures in further investigations. © 2020 Sharif University of Technology. All rights reserved.Item Interfacial behavior of cement stabilized rammed earth: Experimental and numerical study(Elsevier Ltd, 2020) Pavan, G.S.; Ullas, S.N.; Nanjunda Rao, K.S.Cement stabilised rammed earth (CSRE) is a modern earth construction technology witnessing renewed interest by researchers worldwide due to its improved strength and durability vis-a-vis un-stabilised rammed earth (URE). Rammed earth walls are predominantly subjected to compressive loading and occasionally to lateral loads. Strength and deformation ability of interface in rammed earth plays a vital role in case of in-plane lateral loads. The present study focuses on assessing the performance of interface layers in cement stabilized rammed earth elements. Triplet test is conducted on CSRE specimens under dry and saturated condition. Three types of bonding techniques are considered for the interface in CSRE triplets, namely, (i) formation of dents (ii) coating cement slurry across interfacial area (iii) combination of dents and slurry. The influence of stresses normal to the interface of CSRE triplet is also explored in this study. Further, a finite element simulation of the CSRE triplet test is performed. A finite element model of the CSRE triplet is developed by using ABAQUS software. Eight node brick elements are adopted to model the CSRE material and interface. Linear elastic material model is adopted for the CSRE material whereas a PPR-potential based cohesive model is adopted for the interface. Shear stress-displacement curve obtained from the finite element model and experiment are compared with each other and were found to be in reasonable agreement. © 2020 Elsevier LtdItem Identification of critical material thickness for eliminating back reflected shockwaves in laser shock peening – A numerical study(Elsevier Ltd, 2021) Mylavarapu, P.; Bhat, C.; Perla, M.K.R.; Banerjee, K.; Gopinath, K.; Jayakumar, T.Laser Shock Peening (LSP) is one of the emerging surface treatment processes being considered for inducing beneficial compressive surface residual stresses in fatigue critical components. Owing to the ease in handling multiple parameters during optimization of process parameters, simulation based parameterization studies using finite element (FEM) based numerical models are widely gaining importance. Most of the LSP modeling performed so far considered infinite elements in both thickness and lateral directions. However, infinite elements in thickness direction would neglect the deleterious effect of shock wave back reflections for certain sample thicknesses. These back reflections have been reported to result in formation of subsurface cracks in the specimen. Therefore, in this study, using an alternative modeling strategy, effect of thickness on the back reflection of shock waves and its subsequent effect on residual stresses induced are discussed. A 2-D axi-symmetric model with infinite elements in lateral direction and finite elements in thickness direction is developed to simulate a single spot LSP process using ABAQUS/CAE FEM package. It is found that there exists a critical material thickness depending on spot diameter below which the effects of back reflection are predominant. © 2021 Elsevier LtdItem A Numerical Study on the Shear Strength of Pervious Concrete Column in Weak Ground(Southeast Asian Geotechnical Society, 2022) Rashma, R.S.V.; Jayalekshmi, B.R.; Shivashankar, R.In this study, the response of pervious concrete column-treated ground under shear loading is examined by employing a series of numerical analyses. The shear behaviour of pervious concrete column-treated ground is compared with stone column-treated ground and weak ground. Two types of analyses were carried out to assess shear strength of the composite ground. Conventional direct shear test model and large shear test models were evaluated using ABAQUS software. The pervious concrete column-treated ground is observed to have greater shear strength than the mere stone column-treated ground. The lateral deflection pattern of the pervious concrete column is also noticed to be very much lesser than conventional stone columns under static shear loading. The overall shear performance of the pervious concrete column-treated ground is found to be improved than the typical stone column-treated ground. © 2022, Southeast Asian Geotechnical Society. All rights reserved.Item Determining elastic properties of CSEB masonry using FEA-based homogenization technique(Elsevier Ltd, 2023) Shalini, S.; Honnalli, S.; Pavan, G.S.The world today is embracing a sustainable approach in all sectors. The construction industry is grappling with the problem of minimizing energy consumption and lowering carbon emissions involved in the manufacture of construction materials. Soil blocks are an alternative to fired clay bricks. Soil bricks are inexpensive, recyclable, environmentally friendly, and provide better thermal comfort. However, masonry walls built with soil blocks have several drawbacks. They are bulky, have poor durability properties and their strength capacity reduces significantly when saturated due to rain. The remedy for this problem is a Cement Stabilized Earth Block (CSEB). An engineered mixture of soil-sand-cement-moisture compacted at predefined levels offers superior strength and durability properties. The percentage of cement added is minimal in comparison to the soil-sand mixture content. In this study, a numerical model to predict the elastic properties of masonry comprised of CSEB and soil–cement mortar is developed. Both the constituents, CSEBs, and soil–cement mortar have different elastic properties. The presence of bed joints and perpends lends orthotropic behavior to masonry. The present study considers the Finite element analysis (FEA)-based homogenization technique to predict the elastic properties of CSEB masonry. A small periodic part of masonry called a repetitive unit cell (RUC) is considered, which is representative of the block-mortar arrangement in masonry. The three-dimensional masonry RUC is modelled using FE-based ABAQUS-CAE software. A user-defined Python script is developed to apply PBCs (Periodic boundary conditions) to RUC. The six far-field unit strains are applied to the RUC model in three normal and three shear directions. Finally, volume-averaged stress components are computed to determine the elastic properties. The modulus of elasticity and Poisson's ratio of CSEB masonry along three directions are determined. The proposed approach is governed by mechanics and not by empirical relationships and provides satisfactory results. © 2023Item Innovative floating hybrid baffles for improved performance of liquid storage tanks under seismic excitations(Taylor and Francis Ltd., 2025) Jogi, P.; Jayalekshmi, B.R.Liquid storage tanks (LSTs) are highly susceptible to sloshing under dynamic motion, which can compromise their structural stability. This study introduces novel floating wooden and hybrid baffles with a rubber-encased wooden core, offering enhanced energy dissipation and durability. Unlike fixed baffles, their floating design allows for adaptation to changes in liquid levels. Numerical simulations were conducted using ABAQUS to evaluate the performance of these baffles in reducing sloshing-induced responses. The LST, with and without baffles, was subjected to Imperial Valley and Northridge ground motions. Three baffle configurations with varying widths were analyzed for reducing liquid sloshing, hydrodynamic pressures, and enhancing energy dissipation at different liquid depths. The results indicate that the medium-width hybrid baffles reduce the sloshing heights by 51% while maintaining sufficient fluid flow. Hybrid baffles significantly reduced convective pressures by 57% and showed superior energy dissipation than wooden baffles. These findings confirm their effectiveness in controlling liquid sloshing. © 2025 Informa UK Limited, trading as Taylor & Francis Group.Item Sloshing mitigation in liquid storage tanks using vertical floating wooden baffles(Springer, 2025) Jogi, P.; Jyothish, S.S.; Jayalekshmi, B.R.Liquid storage tanks (LSTs) are essential infrastructure but susceptible to failure due to liquid sloshing during seismic events. This sloshing generates additional hydrodynamic forces, which can impose pressure on the tank walls. Conventional methods to mitigate sloshing often rely on rigid internal structures, which can be expensive and inflexible. To overcome these challenges, the present study investigates the effects of lightweight floating wooden baffles that adapt to the liquid level within the tanks, offering a more flexible and cost-effective solution. This research aims to assess the performance of vertical floating wooden baffles in mitigating sloshing within liquid storage tanks. Numerical analysis was conducted on 3D ground-supported rectangular tanks with seven different baffle configurations, including both solid and porous designs, using the arbitrary Lagrangian–Eulerian (ALE) approach in ABAQUS. The models were subjected to horizontal seismic ground motion records from the Imperial Valley and Northridge earthquakes. Critical parameters such as sloshing wave height, hydrodynamic pressures and kinetic energy in the LST were analysed. The findings reveal that porous wooden baffles positioned near the tank walls are particularly effective in reducing sloshing and the associated hydrodynamic forces, offering a cost-efficient solution to enhance the safety of LSTs during seismic events. © Indian Academy of Sciences 2025.