[en] Large scale thermal shock tests have been analysed by pre- and postcalculations with the finite element program ADINA extended by fracture mechanical options based on the J-integral. The results show that temperatures, displacements, strains and stresses can be approximated well. Due to the well-known geometry dependence of specimens' crack resistance in some cases a satisfactory assessment of the crack behaviour can only be obtained by extension of the one-parametric J-integral concept, e.g. with determination of the stress triaxiality in a region in front of the crack tip. Furthermore the influence of residual stresses due to repeated loading of a cracked vessel with plastification at the crack tip seems to be important in fracture assessment. (orig.)