... for spherical shells subjected to displacement-controlled and short-duration dynamic pressure loading is given. This instability condition is evaluated for six plastic and viscoplastic constitutive relations. The role of strain rate sensitivity on the instability point is investigated. Conclusions of this work...

... with the viscoplasticity theory based on overstress. A systematic procedure for determining model parameters is presented and the model is employed to predict the response of the material under various test histories. deformation polymers stress relaxation stress-strain relations tensile strength viscoplasticity...

... reactor accidents fission reactor safety elastoplasticity viscoplasticity finite element analysis nuclear reactor maintenance nuclear engineering computing The rupture of a reactor pressure vessel under a core meltdown accident involves several phenomena such as viscoplastic straining...

.... Within the framework of this program, a model based on Lemaitre and Chaboche with predictive capability in the field of viscoplastic flow, material damage, and failure has been generalized and implemented in CASTEM 2000 finite element code. In order to validate the model in mechanical situations...

... reduction due to plastic coupling reasonably well, but as expected was unable to account for time-dependent stress relaxation. A viscoplasticity model capable of predicting the interaction between stress relaxation and plastic coupling also predicted the plastic coupling reasonably well. The accuracy...