Faculty Publications
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Item A finite difference method assuming parabolic variation of contact pressure distribution is presented to obtain the influence lines for bending moments in beams on an elastic foundation. These influence lines can conveniently be used to find moments in beams on elastic foundations due to any type of loads. The computational procedure presented is simple. Accurate results are obtained with only 10 elements.(Elsevier Ltd, Influence lines for bending moments in beams on elastic foundations) Hosur, V.; Bhavikatti, S.S.1996Item Effect of boundary conditions and convection on thermally induced motion of beams subjected to internal heating(2007) Malik, P.; Kadoli, R.; Ganesan, N.Numerical exercises are presented on the thermally induced motion of internally heated beams under various heat transfer and structural boundary conditions. The dynamic displacement and dynamic thermal moment of the beam are analyzed taking into consideration that the temperature gradient is independent as well as dependent on the beam displacement. The effect of length to thickness ratio of the beam on the thermally induced vibration is also investigated. The type of boundary conditions has its influence on the magnitude of dynamic displacement and dynamic thermal moment. A sustained thermally induced motion is observed with progress of time when the temperature gradient being evaluated is dependent on the forced convection generated due to beam motion. A finite element method (FEM) is used to solve the structural equation of motion as well as the heat transfer equation. © Springer-Verlag 2007.Item Stress analysis of SUS 304 - Ceramics functionally graded beams using third order shear deformation theory(2008) Akhtar, K.; Kadoli, R.Kinematics for moderately thick rectangular beams satisfying zero shear strain on the top and bottom . surfaces is utilized to define the strain displacement relations involving the membrane, bending and higher order of displacements. Strain energy containing shear rotation term is deduced. The principle of stationary potential energy is used to obtain the static finite element equilibrium equations for the FGM (functionally graded material) beam with a uniformly distributed transverse load. FGM beams with continuous and smooth grading of metal and ceramics based on po wer law index are considered for the study. Equivalent single layer approach is followed for the evaluation of the constitutive matrix of the FGM beam. Numerical results are presented on the axialstresses and shear stresses in SUS304-Al3O3, SUS 304-ZrO2 and SUS 304-Si3N4FGM beams with clamped-clamped and simply supported boundary conditions. The effect of volume fraction of ceramic and metal on the nature of stress distribution through the thickness are investigated. The studies reveal that, the magnitude and distribution profile of static stresses in the beam depends on the power law index and also on the nature of load bearing surface, ie, whether the loading is on the ceramic rich face of the beam or metal rich face.Item Strength deformation behaviour of circular concrete filled steel tubes subjected to pure bending(2009) Chitawadagi, M.V.; Narasimhan, M.C.The strength deformation behaviour of circular steel tubes filled with different grades of concrete under flexure is presented. The effects of steel tube thickness, the cross sectional area of concrete, strength of in-filled concrete and the confinement of concrete on moment capacity and curvature of Concrete Filled steel Tubes (CFTs) are examined. Measured flexural strengths are compared with the values predicted by EC4-1994 and LRFD-AISC-1999 code provisions. A total of ninety nine specimens, all one metre long, were tested with concrete fills of 20, 30 and 40 N/mm2 characteristic strength and with D / t ratio 22.3 to 50.8. Based on the experimental results, an interaction model to predict moment and curvature of the CFT sample is developed. © 2009 Elsevier Ltd. All rights reserved.Item Thermo-elastic response of SUS316-Al2O3 functionally graded beams under various heat loads(Elsevier Ltd, 2017) Malik, P.; Kadoli, R.Geometric nonlinearity and temperature dependent material properties are accounted for in the theoretical analysis of time dependent thermo-elastic response of thin functionally graded material (FGM) SUS316-Al2O3 beam subjected to various heat loads. A two dimensional Lagrangian rectangular finite element is used to obtain the temperature distribution on the transverse plane of the beam. Nonlinear thermo-elastic deflection and thermal stresses are evaluated for various structural and thermal boundary conditions. Thermo-elastic oscillations are observed in case of beams subjected to step, concentrated line and shock heat load whereas thermo-elastic deflection is observed for beams subjected to moving heat load. As the thermal load increases, the nonlinear thermal deflection of FGM beam are higher compared to linear analysis. In general, temperature dependency of material properties influence the amplitude of thermal oscillations. High thermal stresses are induced in beams with pin-pin and clamp-pin boundary condition as compared to hinge-hinge beam. © 2017 Elsevier LtdItem Differential quadrature solution for vibration control of functionally graded beams with Terfenol-D layer(Elsevier Inc. usjcs@elsevier.com, 2020) Patil, M.A.; Kadoli, R.The governing differential equation of motion for vibration control of a functionally graded material (FGM) beam using magnetostrictive layers is solved using differential quadrature method(DQM). It is known that, when differential quadrature is implemented directly for the solution of governing differential equation for vibration control of beam, it is required to convert the generalised eigenvalue problem into standard eigenvalue problem. However in the present work, the original differential equation of vibration control of beam is be separated into two simpler second and fourth order differential equations using the separation of variables in conjunction with the characteristics equation of damped single degree of freedom system. Solution of corresponding two simpler differential equation also yields damped natural frequency and damped factor comparable to that of the former approach. It is to be noted that using either of the solutions using differential quadrature method ? point description of the physical domain at boundary is used to obtained the differential quadrature equations for the various boundary conditions of the beam. In order to assure the accuracy of formulation and solution using DQM, convergence behavior of natural frequencies is examined for five combinations of boundary conditions and comparison studies from the two solution approaches is presented. The effect of the location of the magnetostrictive layers, material properties and control parameters on the vibration suppression are investigated. © 2020 Elsevier Inc.Item Process-microstructural features for tailoring fatigue strength of wire arc additive manufactured functionally graded material of SS904L and Hastelloy C-276(Elsevier B.V., 2020) Kannan, A.; Subramaniyan, S.; Pravin Kumar, N.; Siva Shanmugam, N.; Vishnu, A.S.; Palguna, Y.Many engineered components on subjecting to critical environments require properties that slightly differs with location in the fabricated part. The inadequate understanding of wire arc additive manufacturing (WAAM) process-microstructural features correlation brings interests on the structural reliability of functionally graded materials (FGM), which limits the extensive use of this cutting edge technology. Gas metal arc welding (GMAW) based WAAM process was adopted to fabricate the FGM of super austenitic stainless steel SS904L and Hastelloy C-276 with excellent bonding. The micrographs revealed that the WAAM processed FGM was mainly composed of columnar and equiaxed dendrites and had noticeable inhomogeneous features along the built direction. Tensile test results of sample along the built direction revealed a yield strength of 311.08 MPa and tensile strength of 680.73 MPa. Cyclic loading results depicted that the WAAM processed FGM has a fatigue resistance of 156 Mpa after sustaining 2 × 106 cycles. As a result of the varying microstructural characteristics along the built direction, the failure was initiated and fractured at the SS904L weaker region. © 2020 Elsevier B.V.Item Influence of Winkler and viscoelastic foundation on free vibration of functionally graded beam integrated with Terfenol-D layer(Springer Science and Business Media Deutschland GmbH info@springer-sbm.com, 2020) Patil, M.A.; Kadoli, R.Free vibration of functionally graded beam integrated with Terfenol-D layer on Winkler-two parameter and viscoelastic foundation are studied by means of differential quadrature method within the framework of classical beam theory. The material properties of functionally graded beam integrated Terfenol-D layer are estimated by using the rule of mixture. The applied kinematic boundary conditions are implemented using ?-point and modified weighting coefficient approach. The solution of simply supported functionally graded material beam with Terfenol-D layer (FGMT) resting on the Winkler elastic foundation is obtained by using the technique of Navier. The numerical results obtained using differential quadrature method (DQM) and modified differential quadrature method (MDQM) are compared with exact results obtained from analytical formulation where excellent agreement is observed. The parametric study is carried out to encapsulate the influence of Winkler-two parameter and the viscoelastic foundation on the vibration characteristics of functionally graded beams integrated with Terfenol-D layer. © 2020, The Brazilian Society of Mechanical Sciences and Engineering.Item Effect of temperature and moisture on free vibration characteristics of skew laminated hybrid composite and sandwich plates(Elsevier Ltd, 2020) Kallannavar, V.; Kumaran, B.; Kattimani, S.C.This paper is concerned with the effect of variation in temperature and moisture concentration on free vibration response of skew laminated hybrid composite and sandwich plates. The coupled thermo-elastic and hygro-elastic finite element model is formulated using the first-order shear deformation theory (FSDT). Uniform temperature and moisture concentration rise is considered for the analysis. Soft-core viscoelastic materials are considered for the sandwich plates and are modeled using the complex modulus approach. Linear strain-displacement relations are used to develop a mechanical stiffness matrix, and the initial stress stiffness matrix is generated using non-linear strain-displacement relations to represent the non-mechanical stiffness matrix. Numerical examples for the generated finite element model are presented and discussed comprehensively to understand the effect of temperature, moisture concentration, skew angle, length to width ratio, length to thickness ratio, and boundary conditions on the vibration response of the laminated hybrid composite and sandwich plates. Further investigation is devoted to studying the influence of temperature and moisture concentration-dependent material properties, stacking sequence, core to face sheet thickness ratio, and fiber orientation on vibration behavioral response of sandwich and hybrid composite plates. © 2020 Elsevier Ltd