Faculty Publications
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Item Investigation on the Influence of Soft Tissues in Knee Joint on Load Transfer Mechanism during the Gait Cycle(American Institute of Physics, 2024) Raju, V.; Koorata, P.K.Soft tissues keep the human knee joint stable and serve an essential function in limiting motion during daily activities.The goal of this work is to investigate the influence of knee components during a person subjected to walking. A 3D finite element model of a knee joint used for the analysis. The knee kinetics (forces and rotation) during the stance phase of a gait in all degrees of freedom are incorporated into the model. The contact pressure, effective Lagrange strain, maximum shear stress, effective stress and total displacement generated on all the soft tissues are compared. The meniscus shows a more excellent value in all areas concerning other tissues, and for stress values, it is 4 to 5 times greater. The result also indicates that the contact pressure of the tibial cartilage is higher than the femur cartilage throughout the cycle. However, the effective Lagrange strain of femur cartilage is higher than tibial cartilage during the initial phase of the cycle and later declined. These values might help develop comprehensive computational tools to help us better understand the knee injury and disease causes. © 2024 American Institute of Physics Inc.. All rights reserved.Item Behaviour of Masonry Walls under Combined Compression and Shear Loading: 3D Failure Analysis(Elsevier B.V., 2025) Chaitra Shree, V.; Sahana, T.S.; Raveesh, R.M.; Sowjanya, G.V.This study investigates the nonlinear behaviour and failure mechanisms of masonry infill walls subjected to combined axial compression and lateral shear loading. Using the Drucker-Prager plasticity model within ANSYS Workbench, a 3D finite element model of a reinforced concrete (RC) frame with masonry infill was developed. The simulation focused on crack initiation, propagation, and ultimate load-bearing capacity. Results revealed initial stiffness due to confinement, followed by diagonal shear cracking as the dominant failure mode. The finite element analysis showed good agreement with analytical estimations, with a deviation of only ±6% in peak shear capacity. Contour plots of equivalent plastic strain and stress trajectories highlighted the development of tension-induced cracks and residual strength, emphasizing the role of RC confinement. The study validates the Drucker-Prager model for simulating pressure-sensitive masonry behaviour and offers insights into stress redistribution and damage evolution under complex loading. These findings contribute to performance-based design, retrofitting strategies, and structural assessments of masonry-infilled frames under seismic or lateral forces. Future work may incorporate cyclic or probabilistic modelling for enhanced accuracy in real-world applications. © 2025 The Authors.Item Behaviour of Masonry Walls Under Combined Compression and Shear Loading: 3D Failure Analysis(Elsevier B.V., 2025) Chaitra Shree, V.; Sahana, T.S.; Raveesh, R.M.; Sowjanya, G.V.This study investigates the nonlinear behaviour and failure mechanisms of masonry infill walls subjected to combined axial compression and lateral shear loading. Using the Drucker-Prager plasticity model within ANSYS Workbench, a 3D finite element model of a reinforced concrete (RC) frame with masonry infill was developed. The simulation focused on crack initiation, propagation, and ultimate load-bearing capacity. Results revealed initial stiffness due to confinement, followed by diagonal shear cracking as the dominant failure mode. The finite element analysis showed good agreement with analytical estimations, with a deviation of only ±6% in peak shear capacity. Contour plots of equivalent plastic strain and stress trajectories highlighted the development of tension-induced cracks and residual strength, emphasizing the role of RC confinement. The study validates the Drucker-Prager model for simulating pressure-sensitive masonry behaviour and offers insights into stress redistribution and damage evolution under complex loading. These findings contribute to performance-based design, retrofitting strategies, and structural assessments of masonry-infilled frames under seismic or lateral forces. Future work may incorporate cyclic or probabilistic modelling for enhanced accuracy in real-world applications. © 2025 The Authors.Item The effect of subsurface barrier on the motion of the sea water - fresh water interface in coastal equifers is analysed for sudden drawdown conditions. A Galerkin finite element model is used for this purpose to carry out the parametric studies on the effect of location, width and hydraulic conductivity of the barrier. The results indicated marked variations in the interface profile as compared to no barrier condition. The width and hydraulic conductivity play a decisive role in delaying the interface response for any drawdown situations. Among the various barrier locations considered, the barrier at Lo was found to be most effective in checking the intrusion.(Effect of subsurface barrier on salt water intrusion) Mahesha, A.; Babu, M.2001Item Computational investigations on the hemodynamic performance of a new swirl generator in bifurcated arteries(Taylor and Francis Ltd. michael.wagreich@univie.ac.at, 2019) Prashantha, B.; Anish, S.Hemodynamic behaviour of blood in the bifurcated arteries are closely related to the development of cardiovascular disease. The secondary flows generated at the bifurcation zone promotes the deposition of atherogenic particles on the outer walls. The present study aims at suppressing the development of atherosclerosis plaque by inducing helical flow structure in the arterial passage. To realize this objective a novel swirl generator (stent like structure with an internal groove) has been developed to induce helicity in the bifurcated passage. The functional requirement of the swirl generator is to minimize the relative residence time (RRT) of the fluid layer near the endothelial wall without generating any additional pressure drop. Different configurations of the swirl generator have been tested computationally using large eddy simulation (LES) model. It is observed that the induced helical flow redistributes the kinetic energy from the centre to the periphery. A single rib swirl flow generator proximal to the stent treated passage can generate sufficient helicity to bring down the RRT by 36% without generating any additional pressure drop. The swirl flow adds azimuthal instability which increase vortex formations in the passage. The induced helical flow in the domain provokes more linked vortices, which may act as self-cleaning mechanism to the arterial wall. © 2018, © 2019 Informa UK Limited, trading as Taylor & Francis Group.Item Influence of material heterogeneity on the mechanical response of articulated cartilages in a knee joint(SAGE Publications Ltd, 2022) Raju, V.; Koorata, P.K.Structurally, the articular cartilages are heterogeneous owing to nonuniform distribution and orientation of its constituents. The oversimplification of this soft tissue as a homogeneous material is generally considered in the simulation domain to estimate contact pressure along with other physical responses. Hence, there is a need for investigating knee cartilages for their actual response to external stimuli. In this article, impact of material and geometrical heterogeneity of the cartilage is resolved using well known material models. The findings are compared with conventional homogeneous models. The results indicate vital differences in contact pressure distribution and tissue deformation. Further, this study paves way for standardizing material models to extract maximum information possible for investigating knee mechanics with variable geometry and case specific parameters. © IMechE 2022.Item Computational assessment on the impact of collagen fiber orientation in cartilages on healthy and arthritic knee kinetics/kinematics(Elsevier Ltd, 2023) Raju, V.; Koorata, P.K.Background: The inhomogeneous distribution of collagen fiber in cartilage can substantially influence the knee kinematics. This becomes vital for understanding the mechanical response of soft tissues, and cartilage deterioration including osteoarthritis (OA). Though the conventional computational models consider geometrical heterogeneity along with fiber reinforcements in the cartilage model as material heterogeneity, the influence of fiber orientation on knee kinetics and kinematics is not fully explored. This work examines how the collagen fiber orientation in the cartilage affects the healthy (intact knee) and arthritic knee response over multiple gait activities like running and walking. Methods: A 3D finite element knee joint model is used to compute the articular cartilage response during the gait cycle. A fiber-reinforced porous hyper elastic (FRPHE) material is used to model the soft tissue. A split-line pattern is used to implement the fiber orientation in femoral and tibial cartilage. Four distinct intact cartilage models and three OA models are simulated to assess the impact of the orientation of collagen fibers in a depth wise direction. The cartilage models with fibers oriented in parallel, perpendicular, and inclined to the articular surface are investigated for multiple knee kinematics and kinetics. Findings: The comparison of models with fiber orientation parallel to articulating surface for walking and running gait has the highest elastic stress and fluid pressure compared with inclined and perpendicular fiber-oriented models. Also, the maximum contact pressure is observed to be higher in the case of intact models during the walking cycle than for OA models. In contrast, the maximum contact pressure is higher during running in OA models than in intact models. Additionally, parallel-oriented models produce higher maximum stresses and fluid pressure for walking and running gait than proximal-distal-oriented models. Interestingly, during the walking cycle, the maximum contact pressure with intact models is approximately three times higher than on OA models. In contrast, the OA models exhibit higher contact pressure during the running cycle. Interpretation: Overall, the study indicates that collagen orientation is crucial for tissue responsiveness. This investigation provides insights into the development of tailored implants. © 2023 IPEMItem Finite Element Study on Coconut Inflorescence Stem Fiber Composite Panels Subjected to Static Loading(Multidisciplinary Digital Publishing Institute (MDPI), 2024) Muralidhar, M.; Yadav, A.; Prasannakumar, S.; Mahadevaiah, R.R.; Hiremath, P.Natural fiber-reinforced composites (NFCs) are alternatives to synthetic fiber-reinforced composites, since they are abundant in nature, inexpensive, lightweight, and have a high strength-to-weight ratio. Natural fibers encompass a diverse composition, including lignin, hemicellulose, wax, and cellulose. Natural fibers are environmentally friendly, biodegradable, renewable, reusable, and sustainable. In bio-composites, natural fibers such as jute, banana, hemp, coir, kenaf, areca nut, and coconut inflorescence stem fibers, are blended with resin. Natural fiber-reinforced bio-composites have various applications in the construction industry, automobile industry, aerospace industry, sports equipment and gadgets, textile industry, and hotel industry. Fibers from natural sources are also used as reinforcements in composites, such as roofing sheets, bricks, door panels, furniture panels, and panels for interior decoration. The mechanical properties of natural fiber-reinforced composites are profoundly influenced by the bonding between the fibers and the matrix. This study involves the testing of compact tension (CT) specimens under mode I fracture conditions and employs three-dimensional finite element analysis (FEA) using ANSYS software to enhance our understanding of the material’s fracture behavior. Finite element analysis was performed on coconut inflorescence stem fiber-reinforced composite (CIFRC) panels with preformed cracks. Numerical simulation was carried out using ANSYS software. Properties such as crack growth initiation, stress-intensity factor, and stresses along the length of a CIFRC panel were examined using finite element analysis (FEA). ASTM D-5045 standards were followed for the specimen size and the ASTM E399 standard was followed for the finite element pre-cracking. The simulation results were found to be in good agreement with the analytical results. © 2024 by the authors. Licensee MDPI, Basel, Switzerland.Item A Numerical Study on Coconut Inflorescence Stem-Fiber-Reinforced Panels Subjected to Tensile Load, Compressive Load, and Flexural Load(Multidisciplinary Digital Publishing Institute (MDPI), 2024) Muralidhar, M.; Mahadevaiah, R.R.; Parshuram, K.R.B.; Hiremath, P.Natural-fiber-reinforced composites are attracting an increasing amount of interest, and they are becoming more popular as a replacement for synthetic-fiber-reinforced composites. Natural-fiber-reinforced composites are important as a potential building material due to their lightweight nature, strength, and favorable qualities, which include eco-friendliness, non-toxicity, and biodegrad-ability. Natural fibers such as hemp fibers, jute fibers, banana fibers, coconut fibers, sisal fibers, bamboo fibers, areca nut fibers, and kenaf fibers have been used for making composite panels be-cause of their strength-to-weight ratio. Coconut inflorescence stem fibers are considered for our study. Coconut inflorescence stem-reinforced composite panels are often subjected to tensile load, compression load, and flexural load. Tensile strength, compressive strength, and flexural strength play a vital role when these panels are subjected to service loads. In this context, finite element analysis (FEA) is carried out on coconut inflorescence stem-reinforced panels subjected to tensile load, compressive load, and flexural load. A linear analysis is performed for the mechanical properties by using ANSYS workbench 2021 R1. A coconut inflorescence stem-reinforced composite specimen with the dimensions 280 mm × 25 mm × 3 mm (length × width × thickness) for tensile loading, 145 mm × 25 mm × 4 mm for the compressive load, and 150 mm × 25 mm × 4 mm for the flexural load is considered for the present study, as per the ASTM-D3039, ASTM-D3410, and ASTM-D790 standards, respectively. Finite element analysis results showed good correlation with the analytical results. © 2024 by the authors.Item Analysing the flexural response of reinforced concrete cantilever beams under the influence of corrosion: an experimental and numerical study(Cogent OA, 2025) Pandit, P.; Venkataramana, K.The main goal of this study is to evaluate how reinforcement corrosion affects the bending strength of cantilever beams made of reinforced concrete. In the experimental phase, the beams underwent corrosion up to 10% using an accelerated corrosion methodology. Applied corrosion monitoring equipment was employed to gauge the corrosion rate accurately. Following that, corroded beams were tested in the laboratory to examine their flexural behavior. Notably, Portland Pozzolana cement beams exhibited greater corrosion resistance compared to ordinary Portland cement beams, attributed to lower chloride migration in PPC beams, resulting in a 15% increase in corrosion resistance. Additionally, finite element analysis was conducted to develop a numerical analytical approach to effectively evaluate the behaviour of reinforced concrete beams. The research findings revealed that the FE model predicted failure loads to be approximately 11% more than experimental values, while deflections were estimated to be 8% lesser than the experimental value, the FEM model more stiffer than experimental values. © 2024 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.