Abstract
The typical problem in the mechanics of deformable solids comprises a mathematical model in the form of systems of partial differential equations or inequalities. Subsequent investigations are then concerned with analysis of the model to determine its well-posedness, followed by the development and implementation of algorithms to obtain approximate solutions to problems that are generally intractable in closed form. These processes of modelling, analysis, and computation are discussed with a focus on the behaviour of elastic-plastic bodies; these are materials which exhibit path-dependence and irreversibility in their behaviour. The resulting variational problem is an inequality that is not of standard elliptic or parabolic type. Properties of this formulation are reviewed, as are the conditions under which fully discrete approximations converge. A solution algorithm, motivated by the predictor-corrector algorithms that are common in elastoplastic problems, is presented and its convergence properties summarized. An important extension of the conventional theory is that of straingradient plasticity, in which gradients of the plastic strain appear in the formulation, and which includes a length scale not present in the conventional theory. Some recent results for strain-gradient plasticity are presented, and the work concludes with a brief description of current investigations.
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References
Carstensen, C.: Numerical analysis of the primal problem of elastoplasticity with hardening. Numer. Math., 82, 577–597 (1999)
Carstensen, C., Ebobisse, F., McBride, A. T., et al.: Some properties of the dissipative model of straingradient plasticity. Phil. Mag., 97, 693–717 (2017)
Ciarlet, P. G., The Finite Element Method for Elliptic Problems, SIAM, Philadelphia, 2002
Djoko, J. K., Ebobisse, F., McBride, A. T., et al.: A Discontinuous Galerkin formulation for classical and gradient plasticity. Part 1: Formulation and analysis. Comp. Meths. Appl. Mech. Engng, 196, 3881–3897 (2007)
Djoko, J. K., Ebobisse, F., McBride, A. T., et al.: A Discontinuous Galerkin formulation for classical and gradient plasticity. Part 2: Algorithms and numerical analysis. Comp. Meths. Appl. Mech. Engng, 197, 1–21 (2007)
Fleck, N. A., Hutchinson, J. W.: Strain gradient plasticity. Adv. Appl. Mech., 33, 295–361 (1997)
Fleck, N. A., Hutchinson, J. W.: A reformulation of strain gradient plasticity. J. Mech. Phys. Solids, 49, 2245–2271 (2001)
Fleck, N. A., Hutchinson, J. W., Willis, J. R.: Strain–gradient plasticity under non–proportional loading. Proc. R. Soc, A, 470, 20140267 (2015)
Gottschalk, D., McBride, A., Reddy, B. D., et al.: Computational and theoretical aspects of a grainboundary model that accounts for grain misorientation and grain–boundary orientation. Comp. Mat. Sci., 111, 443–459 (2016)
Gudmundson, P.: A unified treatment of strain gradient plasticity. J. Mech. Phys. Solids, 52, 1379–1406 (2004)
Gurtin, M. E., Anand, L.: A theory of strain–gradient plasticity for isotropic, plastically irrotational materials. Part I: Small deformations. J. Mech. Phys. Solids, 53, 1624–1649 (2005)
Gurtin, M. E., Fried, E., Anand, L.: The Mechanics and Thermodynamics of Continua, Cambridge University Press, Cambridge, 2010
Han, W., Reddy, B. D.: Plasticity: Mathematical Theory and Numerical Analysis, Second edition, Springer, New York, 2013
Han, W., Reddy, B. D., Schroeder, G. C.: Qualitative and numerical analysis of quasistatic problems in elastoplasticity. SIAM J. Numer. Anal., 34, 143–177 (1997)
Knees, D.: On global spatial regularity and convergence rates for time dependent elasto–plasticity. Math. Models Meths. Appl. Sci., 20, 1823–1858 (2010)
Martin, J. B, Caddemi, S.: Sufficient conditions for the convergence of the Newton–Raphson iterative algorithm in Incremental elastic–plastic analysis. Euro. J. Mech. A/Solids, 13, 351–365 (1994)
Mielke, A.: Evolution in rate–independent systems, in: Handbook of Differential Equations: Evolutionary Differential Equations, Dafermos, C., Feiereisl, E. (Eds.), Vol.2, Elsevier, 461–559 (2005)
Reddy, B. D.: Existence of solutions to a quasistatic problem in elastoplasticity, in Bandle, C. et al. (Eds.), Progress in Partial Differential Equations: Calculus of Variations, Applications, Pitman Research Notes in Mathematics, 267, Longman, London, 233–259 (1992)
Reddy, B. D.: The role of dissipation and defect energy in variational formulations of problems in straingradient plasticity. Part 1: Polycrystalline plasticity. Continuum Mechanics and Thermodynamics, 23, 527–549 (2001)
Reddy, B. D., Ebobisse, F., McBride, A. T.: Well–posedness of a model of strain gradient plasticity for plastically irrotational materials. Int. J. Plasticity, 24, 55–73 (2008)
Reddy, B. D., Wieners, C., Wohlmuth, B.: Finite element analysis and algorithms for single–crystal straingradient plasticity. Int. J. Numer. Meth. Engng, 90, 784–804 (2012)
Richtmyer, R. D., Morton, K. W.: Difference Methods for Initial–Value Problems, 2nd Edition, Interscience Pub., New–York, 1967
Schröder, A., Wiedemann, S.: Error estimates in elastoplasticity using a mixed method. Appl. Numer. Math., 61, 1031–1045 (2011)
Simo, J. C., Taylor, R. L.: Consistent tangent operators for rate–independent elasto–plasticity. Comp. Meth. Appl. Mech. Engng, 48, 101–118 (1985)
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Supported by National Research Foundation through the South African Chair in Computational Mechanics (Grant No. 47584)
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Reddy, B.D. Modelling, Analysis and Computation in Plasticity. Acta. Math. Sin.-English Ser. 35, 64–82 (2019). https://doi.org/10.1007/s10114-018-7477-z
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DOI: https://doi.org/10.1007/s10114-018-7477-z
Keywords
- Elastoplasticity
- variational inequalities
- finite elements
- algorithms
- convergence
- predictor- corrector schemes
- strain-gradient plasticity