Laxmikant Gupta - Academia.edu (original) (raw)
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Papers by Laxmikant Gupta
Extension of the effort to demonstrate application of Computational Fluid Dynamics (CFD) techniqu... more Extension of the effort to demonstrate application of Computational Fluid Dynamics (CFD) technique to obtain Pressure Coefficients on a single roof gabled like closed structure using ANSYS-Flotran module, proves a necessity to understand influence of various associated parameters. In pre-study kind of it, graphically obtained results are compared with data obtained from full-scale study as well with computational results published in literature to validate modeling methods and components. Collectively, computational results are absolutely sensitive to various parameters like meshing size & patterns, application of boundary conditions, turbulence models, domain size used to model flow environment like height of domain, upstream length L1(distance between inlet plane to windward face),downstream length L2(distance between leeward face to outlet plane). Using validated procedures and input parameters conducted before, parametric study is carried out to present the influence of geometrical parameters like fluid domain sizes on pressure coefficient prediction. At the end, concluding remarks derived, provide the important guidelines for fixing up the fluid domain size for 2-D simulation in ANSYS FLOTRAN.
The use of steel beams with web openings (SBWOs) for structures such as industrial buildings and ... more The use of steel beams with web openings (SBWOs) for structures such as industrial buildings and high-rise buildings has turned out to be extensive in recent times. There are numerous motives for which openings are kept. In this respect, an experimental investigation was planned and conducted on seven models of SBWOs. The initiative was to identify the maximum load behaviour, and deflection of steel beams with openings in the web. The performance of such beams has been considered only for vertical loads. Hot rolled steel beams of ISMB 100 with openings in the web were tested to failure. The beams were simply supported at the ends and subjected to a concentrated load applied at the mid-span. The openings considered in the experimental study are circular and rectangular only. All the beams were analysed by the finite element method by using general finite element analysis software ANSYS and the results were compared with those obtained experimentally. The test results found to be very useful for optimization of spacing-to-diameter ratio and aspect ratio of openings. The finite element results for deformation and ultimate strength shows good agreement with the corresponding values observed in the experiments. At last, a parametric study was carried out using finite element method to examine that which type of openings gives best performance during loading.
International Journal of Advanced Structural Engineering, 2012
Vehicle collision on bridge piers is no more a rare possibility with crowded city roads, encroach... more Vehicle collision on bridge piers is no more a rare possibility with crowded city roads, encroached spaces, and lack of recommended margins around piers. An attempt is made through this study to investigate the plasticity induced in a pier due to a colliding vehicle. Responses of several piers with varying geometries are studied by finite element analysis. The piers are subjected to collision loads, static as well as dynamic in nature. The study aims at identifying the areas of damage and roughly estimating the damage sustained by the pier under consideration. A range of results in the form of graphs have been presented. Subroutines capable of handling material nonlinear effects in the static as well as dynamic zones were developed using MATLAB. The programs were validated using ANSYS. Separate results are presented for static and dynamic analysis. The forces considered for static analysis are based on specifications of several countries, while the force-time histories adopted for transient elastoplastic response of the pier are adopted from simulated crash test results. An attempt is made to get a better insight into quantifying damage with plasticity as an indicator.
International Journal of Advanced Structural Engineering, 2012
This paper presents the structural behavior of composite concrete slabs with CRIL DECKSPAN TM (Co... more This paper presents the structural behavior of composite concrete slabs with CRIL DECKSPAN TM (Colour Roof India Limited (CRIL), Mumbai, INDIA) type profiled steel decking by experimental and analytical studies. The slab is created by composite interaction between the concrete and steel deck with embossments to improve their shear bond characteristics. However, it fails under longitudinal shear bond due to the complicated phenomenon of shear behavior. Therefore, an experimental full-size tests has been carried out to investigate the shear bond strength under bending test in accordance to Eurocode 4 -Part 1.1. Eighteen specimens are split into six sets of three specimens each in which all sets are tested for different shear span lengths under static and cyclic loadings on simply supported slabs. The longitudinal shear bond strength between the concrete and steel deck is evaluated analytically using m-k and partial shear connection (PSC) methods and compared the values. The experimental results is verified and compared with the results of both m-k and PSC methods. Comparison of experimental and analytical results of the load-carrying capacity of composite slabs revealed that agreements between these values are sufficiently good. As a result, m-k method proved to be more conservative than PSC method.
Steel I-shaped beams with web openings of shapes like hexagonal, circular and rectangular at regu... more Steel I-shaped beams with web openings of shapes like hexagonal, circular and rectangular at regular intervals have been used since last 60-70 years. Therefore aim of this paper is to examine the behaviour of steel I-beams with rectangular web openings by performinganexperimental and parametric study. A parametric study based on finite element analysis consists of effect of fillet radius, aspect ratio of rectangular openings, stiffeners position around the openings and effect of positions of openings on load carrying capacities of steel beam with rectangular web openings was carried out by using a commercial finite element software ANSYS v.12. An overall study of such type of beam was carried out and results shows that rectangular openings having fillet radius either 2 times thickness of web or 25 mm (whichever is minimum), aspect ratio of 1.6 and reinforcement either in the form of horizontal or vertical stiffeners around the web openings found to be very effective. The fillet radius and stiffeners also affect the stress distribution around the corner regions of openings. Load carrying capacities of perforated beams are almost equal to plain-webbed beams, when openings are placed within middle two-third(neutral zone) of the span.
Extension of the effort to demonstrate application of Computational Fluid Dynamics (CFD) techniqu... more Extension of the effort to demonstrate application of Computational Fluid Dynamics (CFD) technique to obtain Pressure Coefficients on a single roof gabled like closed structure using ANSYS-Flotran module, proves a necessity to understand influence of various associated parameters. In pre-study kind of it, graphically obtained results are compared with data obtained from full-scale study as well with computational results published in literature to validate modeling methods and components. Collectively, computational results are absolutely sensitive to various parameters like meshing size & patterns, application of boundary conditions, turbulence models, domain size used to model flow environment like height of domain, upstream length L1(distance between inlet plane to windward face),downstream length L2(distance between leeward face to outlet plane). Using validated procedures and input parameters conducted before, parametric study is carried out to present the influence of geometrical parameters like fluid domain sizes on pressure coefficient prediction. At the end, concluding remarks derived, provide the important guidelines for fixing up the fluid domain size for 2-D simulation in ANSYS FLOTRAN.
The use of steel beams with web openings (SBWOs) for structures such as industrial buildings and ... more The use of steel beams with web openings (SBWOs) for structures such as industrial buildings and high-rise buildings has turned out to be extensive in recent times. There are numerous motives for which openings are kept. In this respect, an experimental investigation was planned and conducted on seven models of SBWOs. The initiative was to identify the maximum load behaviour, and deflection of steel beams with openings in the web. The performance of such beams has been considered only for vertical loads. Hot rolled steel beams of ISMB 100 with openings in the web were tested to failure. The beams were simply supported at the ends and subjected to a concentrated load applied at the mid-span. The openings considered in the experimental study are circular and rectangular only. All the beams were analysed by the finite element method by using general finite element analysis software ANSYS and the results were compared with those obtained experimentally. The test results found to be very useful for optimization of spacing-to-diameter ratio and aspect ratio of openings. The finite element results for deformation and ultimate strength shows good agreement with the corresponding values observed in the experiments. At last, a parametric study was carried out using finite element method to examine that which type of openings gives best performance during loading.
International Journal of Advanced Structural Engineering, 2012
Vehicle collision on bridge piers is no more a rare possibility with crowded city roads, encroach... more Vehicle collision on bridge piers is no more a rare possibility with crowded city roads, encroached spaces, and lack of recommended margins around piers. An attempt is made through this study to investigate the plasticity induced in a pier due to a colliding vehicle. Responses of several piers with varying geometries are studied by finite element analysis. The piers are subjected to collision loads, static as well as dynamic in nature. The study aims at identifying the areas of damage and roughly estimating the damage sustained by the pier under consideration. A range of results in the form of graphs have been presented. Subroutines capable of handling material nonlinear effects in the static as well as dynamic zones were developed using MATLAB. The programs were validated using ANSYS. Separate results are presented for static and dynamic analysis. The forces considered for static analysis are based on specifications of several countries, while the force-time histories adopted for transient elastoplastic response of the pier are adopted from simulated crash test results. An attempt is made to get a better insight into quantifying damage with plasticity as an indicator.
International Journal of Advanced Structural Engineering, 2012
This paper presents the structural behavior of composite concrete slabs with CRIL DECKSPAN TM (Co... more This paper presents the structural behavior of composite concrete slabs with CRIL DECKSPAN TM (Colour Roof India Limited (CRIL), Mumbai, INDIA) type profiled steel decking by experimental and analytical studies. The slab is created by composite interaction between the concrete and steel deck with embossments to improve their shear bond characteristics. However, it fails under longitudinal shear bond due to the complicated phenomenon of shear behavior. Therefore, an experimental full-size tests has been carried out to investigate the shear bond strength under bending test in accordance to Eurocode 4 -Part 1.1. Eighteen specimens are split into six sets of three specimens each in which all sets are tested for different shear span lengths under static and cyclic loadings on simply supported slabs. The longitudinal shear bond strength between the concrete and steel deck is evaluated analytically using m-k and partial shear connection (PSC) methods and compared the values. The experimental results is verified and compared with the results of both m-k and PSC methods. Comparison of experimental and analytical results of the load-carrying capacity of composite slabs revealed that agreements between these values are sufficiently good. As a result, m-k method proved to be more conservative than PSC method.
Steel I-shaped beams with web openings of shapes like hexagonal, circular and rectangular at regu... more Steel I-shaped beams with web openings of shapes like hexagonal, circular and rectangular at regular intervals have been used since last 60-70 years. Therefore aim of this paper is to examine the behaviour of steel I-beams with rectangular web openings by performinganexperimental and parametric study. A parametric study based on finite element analysis consists of effect of fillet radius, aspect ratio of rectangular openings, stiffeners position around the openings and effect of positions of openings on load carrying capacities of steel beam with rectangular web openings was carried out by using a commercial finite element software ANSYS v.12. An overall study of such type of beam was carried out and results shows that rectangular openings having fillet radius either 2 times thickness of web or 25 mm (whichever is minimum), aspect ratio of 1.6 and reinforcement either in the form of horizontal or vertical stiffeners around the web openings found to be very effective. The fillet radius and stiffeners also affect the stress distribution around the corner regions of openings. Load carrying capacities of perforated beams are almost equal to plain-webbed beams, when openings are placed within middle two-third(neutral zone) of the span.