Faculty Publications
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Item Finite Element Modelling and Experimental Validation of Strain Gauge Pasted Over the Surface of a Substrate Subjected to a Transverse Load(Springer, 2024) Raveesh, R.M.; Kaliveeran, V.; Kundapura, S.The strain measurement is important as it directly involves with the deformation of a structure in the field of engineering. Strain is a measure of change in shape that occurs when an external load is applied to an engineering assembly. The evaluation of the strain is used to determine the amount of extension or deformation a structure experiences under different loading conditions. Strain gauges are electrical resistance sensors bonded at critical locations on the surface of structural components to detect surface deformation. Strain gauges are frequently used to continuously check for deformations to avoid accidents that can occur in nuclear power plants, aerospace vehicles, mechanical components, and structures. Strain gauges applied directly to the specimen are partially affected by the bonding material and thickness when tested. Present work intends to study the effect of adhesive thickness on strain values. Adhesives are used to paste strain gauges over the surface of the specimen. Three-Dimensional analysis of the strain gauge model has been carried out with the aid of the Finite element software. Experiments were conducted to study the effect of adhesive thickness by varying the thickness of the adhesive from 0.1 to 1 mm by pasting strain gauge over the surface of the Aluminium specimen of length 230 mm, width of 30 mm, and thickness of 6 mm. The strain values obtained from the finite element analysis were compared with the strain values obtained from the experiments. Finite element analysis results were found to be in good correlation with the experimental results. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.Item Design and Analysis of Filler Slab(IOP Publishing Ltd, 2020) Mahananda, R.K.; Mendi, V.; Raveesh, R.M.Filler slab technology is an innovative and cost effective technology where the dead load of slab is reduced by replacing the concrete with filler material. The concept behind the use of filler-slab technology is to reduce a substantial portion of concrete in the tension zone, since all the concrete in the tension zone does not contribute to the tensile properties. This concrete is replaced with lightweight, inert and inexpensive filler without compromising with the quality and structural stability of the structure. Two-way slab is designed; the filler blocks are placed between the reinforcement spacing by providing a cover of 20mm. The filler materials are granite dust and foundry sand. This filler slab is analyzed using STAAD.Pro and ANSYS software. Filler slab is compared with the conventional slab of same size. This study describes the Structural behavior and cost effectiveness of filler slab when compared to the standard slab. © Published under licence by IOP Publishing Ltd.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 Experimental Investigation on Strength Characteristics of Concrete Incorporating Aluminium Dross as Cement Substitute(Elsevier B.V., 2025) Siddesh, K.N.; Sowjanya, G.V.; Raveesh, R.M.; Sahana, T.S.The enhancement of shear performance of reinforced cement concrete beams by using aluminum waste as a partial replacement of cement has gained significant importance in recent times. The study focusses on dual challenges of sustainable construction and effective waste management, by incorporating aluminum dross-a byproduct of the aluminum industry as a partial replacement for cement in reinforced concrete beams. Firstly, the cubes are casted with varying % of aluminum dross by the weight of cement. The cement has been replaced with aluminum dross in finely powdered form by its weight varying from 0%, 5%, 10%, 15%, 20%, 25% and 30%. A series of experiments were conducted to find the range of optimum replacement levels. In that range, reinforced cement concrete beams are casted, again series of experiments were conducted to obtain optimum replacement % and finite element modelling were made to evaluate the shear performance and to validate the result. The results reveal that a 10% replacement of cement with aluminum dross yields the optimum performance, showing improved mechanical strength compared to the control mix. Beyond this dosage, a decline in strength was observed. The results from experiments shows significant improvement in shear strength or shear capacity till optimum replacement levels beyond which shear performance declines. Incorporating aluminum dross not only improves mechanical properties but also reduces cement usage, focusing on sustainability goals. The study demonstrates that aluminum dross can be effectively utilized as a sustainable alternative in cementitious materials, contributing to both environmental protection and economic benefits. © 2025 The Authors.Item Experimental Investigation on Strength Characteristics of Concrete Incorporating Aluminium Dross as Cement Substitute(Elsevier B.V., 2025) Siddesh, K.N.; Sowjanya, G.V.; Raveesh, R.M.; Sahana, T.S.The enhancement of shear performance of reinforced cement concrete beams by using aluminum waste as a partial replacement of cement has gained significant importance in recent times. The study focusses on dual challenges of sustainable construction and effective waste management, by incorporating aluminum dross-a byproduct of the aluminum industry as a partial replacement for cement in reinforced concrete beams. Firstly, the cubes are casted with varying % of aluminum dross by the weight of cement. The cement has been replaced with aluminum dross in finely powdered form by its weight varying from 0%, 5%, 10%, 15%, 20%, 25% and 30%. A series of experiments were conducted to find the range of optimum replacement levels. In that range, reinforced cement concrete beams are casted, again series of experiments were conducted to obtain optimum replacement % and finite element modelling were made to evaluate the shear performance and to validate the result. The results reveal that a 10% replacement of cement with aluminum dross yields the optimum performance, showing improved mechanical strength compared to the control mix. Beyond this dosage, a decline in strength was observed. The results from experiments shows significant improvement in shear strength or shear capacity till optimum replacement levels beyond which shear performance declines. Incorporating aluminum dross not only improves mechanical properties but also reduces cement usage, focusing on sustainability goals. The study demonstrates that aluminum dross can be effectively utilized as a sustainable alternative in cementitious materials, contributing to both environmental protection and economic benefits. © 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 Bond strength characteristics of masonry using hemp fibre and chicken mesh reinforced mortar(Elsevier Ltd, 2023) Mahesh, J.V.; Ramya, S.; Marulasiddappa, B.M.; Raveesh, R.M.The bonding between the masonry unit and mortar plays very important role in strength of masonry. To improve the bond strength, we need to concentrate on the mortar properties. The present study focusses on the bond strength of masonry by adding reinforcement for the mortar. The hemp fibre and chicken mesh are used as a reinforcement for the mortar. For the test masonry triplets are used with mortar of proportion 1:4. The optimum dosage for hemp fibre is found to be 2% and chicken mesh is added along with mortar joints. The bond strength was tested in universal testing machine and the results have compared each other. From the study it was found that, the bond strength of hemp fibre reinforced triplets is found to be 27% higher than the chicken mesh reinforcement and 73% higher than the unreinforced mortar masonry. © 2023Item Experimental and Numerical Studies on the Stiffening of Tubular T-joint of Offshore Jacket Structures(Springer Science and Business Media Deutschland GmbH, 2024) Murugan, N.; Kaliveeran, V.; Raveesh, R.M.; Kundapura, S.Present study investigates the stiffening effect on the behavior of tubular T-joints in offshore platform jacket structures subjected to axial compression. Stiffening is crucial to enhance the structures' strength and lifetime. Tubular cross section structures are preferred due to their mechanical properties and cost-efficiency. The study introduces an innovative technique by adding stiffeners at the interface between braces and chords to effectively distribute loads from multiple directions. The T-joint specimen used has specific dimensions: Chord length 400 mm, brace length 200 mm, chord diameter 100 mm, brace diameter 50 mm, chord thickness 4 mm, and brace thickness 3 mm. Experimental tests and Numerical simulations were conducted to measure failure loads for both stiffened and unstiffened T-joints. Stiffened configurations (4, 6, and 8 strips) has a notable impact on the ultimate capacity of the T-joint, showcasing an increase in strength compared to the unstiffened joint. Stiffened joints showed a significant increase in ultimate strength compared to unstiffened joints, with improvements ranging from 67.18 to 73.33% for different stiffener configurations. Joint local stiffness also improved substantially, with percentage increases ranging from 67.03 to 140.80% for various stiffener configurations. Present research work demonstrates the positive impact of stiffeners on tubular T-joints, improving their strength and stiffness while showing strong agreement between numerical simulations and experimental results and the study also concludes that the addition of stiffeners effectively enhances the ultimate capacity and local stiffness of tubular T-joints. These findings emphasize the effectiveness of the proposed reinforcement strategies for optimizing tubular T-joints in offshore structures. © The Author(s), under exclusive licence to Shiraz University 2023.Item Development and Performance Evaluation of a Block-Stiffened Fretting Fixture for Accurate Load Transfer in Fretting Tests(Springer Science and Business Media Deutschland GmbH, 2025) Bangaru, P.; Kaliveeran, V.; Raveesh, R.M.; Kundapura, S.This study introduces a novel fretting fixture designed for fretting and full sliding tests, which minimizes recalibration and integrates multiple sensors for measuring contact tractions. The fixture features an additional “Z”-type supporting structure that enables horizontal chassis length adjustments and is compatible with various fatigue testing machines. Adjustable components, such as vertical stiffeners reinforced with rigid blocks, facilitate achieving the target Load Transfer Ratio (LTR) of 50%. The LTR can be adjusted by repositioning the rigid blocks using a bolt-nut assembly. The fretting tests are conducted with and without blocks attached to the vertical stiffeners. Finite Element Analysis (FEA) and experimental methods are employed to ealuate the LTR, yielding results of 59–60% and 58–59%, respectively. Supported by FEA and experimental validation, the fixture demonstrates effectiveness and reliability for fretting studies. The stiffened fretting fixture is evaluated under higher normal loads and increased frequencies, showing a notable increase in the Q/P ratio. This increase highlights intensified surface interaction and pronounced tribological effects. © The Society for Experimental Mechanics, Inc 2025.Item Wear and Friction Behavior of Stainless Steel and Aluminium Alloys: Role of Pin Diameter and Track Size in Dry Sliding Experiments(The Aeronautical and Astronautical Society of the Republic of China, 2025) Raveesh, R.M.; Kaliveeran, V.; Kundapura, S.Tribological characterization of materials is critical due to their extensive use in various industrial applications, where friction and wear significantly affect performance and longevity. Tribological studies helps to identify the material suitability for specific applications based on wear resistance, frictional performance, and durability under given conditions. Stainless steel (SS304, SS304L, SS316) and aluminium (Al6061, Al6082) alloys, were selected to understand their performance in dry sliding conditions. This study presents a comparative tribological analysis of stainless steels (SS304, SS304L, SS316) and aluminium alloys (Al6061, Al6082) under dry sliding conditions using a pin-on-disk tribometer. The novelty lies in evaluating the influence of pin diameter (6 mm and 8 mm) and track diameter (60–120 mm) on wear rate and coefficient of friction (CoF). Results show that Al6061 exhibited the highest wear rate (0.0676 mm3/N·m) and CoF up to 0.7, particularly under 20 N load and small track diameter (60 mm). In contrast, SS316 demonstrated the lowest wear rate (0.0023 mm3/N·m) and stable CoF (0.4), particularly under 10 N load and larger track diameter (120 mm), indicating superior wear resistance. The study reveals that smaller pin and track diameters intensify contact stress, accelerating wear in softer materials. © 2025 The Aeronautical and Astronautical Society of the Republic of China. All rights reserved.