A finite element multiscale capability for nonlinear quasistatic stress analysis

Failure modeling is inherently a multi length scale phenomenon that requires a failure model and a computational method that solves for stress/strain gradients at interesting locations. Focusing on the computational method, we recognize that the mesh resolution must be relatively fine in regions where failure is expected and relatively coarse elsewhere. Furthermore, in some modeling approaches the topology in the structural model is different than that required in the fine scale model where failure is to be predicted. This necessarily precludes approaches such as h-adaptivity. We are therefore led to consider multiscale approaches to solve these problems.This work describes an approach to solve multiple (a reference scale and fine scale) coupled boundary value problems for the purpose of nonlinear quasistatic stress analysis. Two examples are included: one example illustrates the multiscale solution strategy to perform quasistatic stress analysis and the other demonstrates the computational beginnings of the ability to model material failure.