A NEW A-POSTERIORI ERROR ESTIMATION FOR NONLINEAR TIME-DEPENDENT FINITE-ELEMENT ANALYSIS

In this paper, an error on the constitutive law (labeled the dissipati on error) is used to measure the quality of finite element computation s of plastic and viscoplastic structures whose behavior is described b y internal variables. This measure takes into account all the classica l sources of error involved in the computation: the space discretizati on (the mesh), the time discretization and the iterative technique use d to solve the nonlinear discrete problem. More specifically, to quant ify the quality of the space and time discretizations, two quantifies, called indicators, are introduced. The efficiency of both the error a nd the indicators is shown for several examples. (C) 1998 Elsevier Sci ence S.A.