Abstract
The modelling of plastic beams experiencing softening is studied. The homogeneous cantilever beam loaded by a concentrated force at its extremity is considered. This simple structural problem with gradient bending moment allows an analytical treatment of the evolution problem. A gradient plasticity model is developed in order to overcome Wood’s paradox. Surprisingly, explicit gradient plasticity models do not eliminate this paradox, since the beam response is found to be not continuous with respect to the loading parameter. A new implicit gradient plasticity model is used in this paper. It is shown that the new regularized problem is well-posed. Closed-form solutions of the elastoplastic deflection are finally derived. These results are valid for the beam bending problem, but also for the simple analogy of the bar subjected to distributed axial force.
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Challamel, N. A regularization study of some softening beam problems with an implicit gradient plasticity model. J Eng Math 62, 373–387 (2008). https://doi.org/10.1007/s10665-008-9233-3
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DOI: https://doi.org/10.1007/s10665-008-9233-3