engleski

Numerical modelling of deformation responses of cracked tubes

Three-dimensional linear and non-linear finite element analyses have been carried out to determine the stress intensity factors, the J-integral and the plastic limit loads for external axial semi-elliptical surface cracks in VVER steam generator tubes under internal pressure. The results for the stress intensity factors and J-integral are presented in terms of the well-known GE/EPRI influence functions to allow comparisons with some results available in the literature. The plastic limit pressure solutions have been developed on the basis of finite element limit load analyses employing elastic-perfectly plastic material behaviour. Using these solutions, a new analytical approximation of the plastic limit pressure has been derived for a wide range of cracks. The proposed stress intensity factors, J-integral and analytical approximation of limit pressure provide very useful tools for assessing of the integrity of pressurized tubes

finite element method; tubes; surface cracks; fracture analysis; plastic limit analysis; stress intensity factor; J-integral; plastic limit pressure

Rad u časopisu navedenom u Pravilniku iz NN 2/87.