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Prof. Kant developed interest in computational methods of structural analysis and theories of plates and shells during his Master’s study at IIT Kanpur during 1967-‘69. His MTech dissertation which tackled clamped-clamed and clamped-simply supported boundary conditions over curved edges and free conditions over the longitudinal edges of a single and multi-barrel cylindrical shell quite effectively. This encouraged him to write his first technical paper and publish which also earned him an award.

Professor Kant was quite ahead of his time when he chose the difficult topic of elastic shells and initiated research on two dimensional (2D) higher order theories for predicting realistic behavior of thick three dimensional (3D) physical shells discarding most of the assumptions in the classical Love shell theory [Ref. Kant, T. (1976), Thick Shells of Revolution-Some Studies. Ph.D. Thesis, Indian Institute of Technology Bombay; Kant, T. and Ramesh, C.K. (1976), Analysis of thick orthotropic shells, in Proc. IASS World Congress on Space Enclosures, Montreal, Canada, 4-9 July, pp. 401-409]. During the course of this study, for practical analysis, he developed and perfected a numerical integration (NI) technique involving the so-called segmentation which could capture the boundary layer effects inherent in the shell equations [Ref. Kant, T. and Ramesh, C.K. (1981), Numerical integration of linear boundary value problems in solid mechanics by segmentation method, International Journal for Numerical Methods in Engineering 17, 1233-1256]. Later, he improved on his earlier work and extended it to include composite materials [Ref. Kant, T. (1981), A higherorder general shell theory, Rep. C/R/391/81, University of Wales, Swansea; Kant, T. (1981), A higher-order general laminated shell theory, Rep. C/R/395/81, University of Wales, Swansea]. These developments were not only significant but are now regarded as pioneering works in the then nascent area of higher order theories of elastic beams, arches, plates and shells.

One of his thesis examiners, Dr. MVV Murthy [of National Aerospace Laboratories (NAL) Bengaluru] got so much influenced that later as a NASA Fellow at the Langley Research Centre wrote a technical note on composite plates that became a forerunner for future research in the area. Later, Prof. Kant got interested in the mechanics of multilayered fibre reinforced polymer composites (FRPCs) and finite element (FE) modelling. A laminate is a multilayered composite made up of several individual layers (laminae), in each of which the fibres are oriented in a predetermined direction to provide efficiently the required strength and stiffness parameters. Development of two dimensional (2D) accurate plate/ shell analytical models, of these physically three dimensional (3D) laminates, has been an area of active research since early 1960s. Prof. Kant has made significant pioneering contributions to the mechanics of FRPCs which has led to better understanding of their behaviour. Realizing the importance of application of these new materials in high technology areas, he initiated a systematic research effort, way back in the year 1980, towards development of both continuum and discrete FE higher order deformation models for improved response characteristics of the laminates in the form of beams, plates and shells. He was the first to derive the consistent mathematical model, based on a displacement based variational principle, for a Co higher order plate theory [Kant, T. (1982), Numerical analysis of thick plates, Computer Methods in Applied Mechanics and Engineering 31, 1-18]. These efforts were initially directed towards construction of simple Co FEs for applications to real life problems. His demonstration of Co FE formulation of higher order displacement theories is considered as a pioneering work by his peers and is now being extensively used [Kant, T., Owen, D.R.J. and Zienkiewicz, O.C. (1982), A refined higher-order Co plate bending element, Computers and Structures 15, 177-183]. He and his co-workers have clearly demonstrated the application of these analytical and computational models to a variety of problems in structural engineering. He also busted the myth prevalent around the so-called a parallel C1 formulation for plates in which the free surface conditions are additionally enforced by numerically showing that their Co formulation produced most accurate results for displacements and stresses [Kant, T. and Swaminathan, K. (2002), Analytical solutions for the static analysis of laminated composite and sandwich plates based on a higher order refined theory, Composite Structures 56, 329-344]. The accuracy of their Co model over C1 model has also been independently confirmed [Ref. Rohwer, K. (1992), Application of higher order theories to the bending analysis of layered composite plates, International Journal of Solids and Structures 29, 105-119; Rohwer, K. and Rolfes, R. (2004), Stress analysis of laminated structures from fiber-reinforced composite materials, Proc. International Congress on Computational Mechanics and Simulation 2004 (ICCMS2004), Vol. 1, IIT Kanpur, 21-42]

Most plate/shell theory solutions in neighbourhood of the boundary are very sensitive to boundary conditions; the solutions vary sharply in the edge zones. This is called boundary layer effect which is present in the solutions of the exact 3D formulations and thus it is a reality. Unfortunately, FE method was not suitable for capturing such steep stress gradients while the experience with the NI technique for such evaluations was extremely encouraging. Recently, Prof. Kant and his associates have shown, for the first time, the effectiveness of a new partial/semi discretization methodology through marriage of FE and NI approaches specifically for evaluation of interlaminar stresses in layered composites and in general indeed an unique semi discretization method, for equilibrium problems [Kant, T., Pendhari, S.S. and Desai, Y.M. (2007), A general partial discretization methodology for interlaminar stress computation in composite laminates, Computer Modeling in Engineering & Science 17(2), 135-161].

The papers written by Prof. Kant and his associates give not only the mathematical models but describe the powerful finite element computational models as well as the analytical methods for the thermo-mechanicalpiezoelectric behaviour of fibre reinforced composite/ functionally graded laminates used in the form of beams, arches, plates and shells for the three types of analyses, i.e., equilibrium, eigenvalue and transient, encountered in practice and in a significant way, highlight the research contributions made to the scientific literature by Professor Tarun Kant and his associates.