On the simultaneous estimation of model parameters used in constitutive laws for inelastic material behaviour

The paper deals with the simultaneous estimation of parameters used in cons titutive laws for modeling inelastic material behaviour. Experimental data is obtained from specimens with a uniform distribution of stresses. Uniaxia l evaluations of the constitutive laws are used. Due to the numerical stiff ness of the constitutive equations, it is shown that it is necessary to use an implicit time-integration scheme. The model parameters are estimated fr om experimental data using a least-squares criterion. Stochastic and determ inistic optimization methods are used. The algorithms are parallelized on t he basis of the master-slave paradigm. Since a complete parameter estimatio n requires error estimates and confidence regions, statistic methods are im plemented. (C) 1999 Elsevier Science Ltd. All rights reserved.