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arXiv · 1509.08681

Finite plasticity in $P^T P$

Diego Grandi·Ulisse Stefanelli
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Abstract

We discuss a finite-plasticity model based on the symmetric tensor $P^T P$ instead of the classical plastic strain $P$. Such a model structure arises from assuming that the material behavior is invariant with respect to frame transformations of the intermediate configuration. The resulting variational model is lower-dimensional, symmetric, and based solely on the reference configuration. We discuss the existence of energetic solutions both at the material-point level and for the quasistatic boundary-value problem. These solutions are constructed as limits of time discretizations. Eventually, the linearization of the model for small deformations is ascertained via a rigorous evolutive-$\Gamma$-convergence argument.

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Diego Grandi, Ulisse Stefanelli. 2015-09-29. Finite plasticity in $P^T P$. https://arxiv.org/abs/1509.08681

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