Error estimation including pollution assessment for nonlinear finite element analysis

A residual type error estimator for nonlinear finite element analysis is in troduced. This error estimator solves local problems avoiding both the comp utation of the flux jumps and the associated flux splitting procedure. Poll ution errors are taken into account by a feedback strategy, that is, an err or estimate based on local computations is used as the input of the polluti on analysis. This estimator is used in the Frame of an adaptive procedure. Numerical examples show that the estimator is able to drive adaptive proced ures leading to likely good solutions. Moreover, one of the examples demons trates that adaptive procedures are essential for complex highly nonlinear mechanical problems because they may discover secondary collapse mechanisms . (C) 2000 Elsevier Science S.A. All rights reserved.