An elastic/viscoplastic model for transient creep of rock salt (Q1271136)

Using the triaxial test results on Gorleben rock salt, we formulate a new elastic/viscoplastic model for transient creep. Both yield function and viscoplastic potential are determined from experimental data. Singularity and asymptotic properties of the yield surfaces and viscoplastic potential are considered, and a new procedure to determine the viscoplastic potential is proposed. Incorporated in a finite element program, the model shows a good agreement with experimental data. As an example, the stress distribution around a vertical cylindrical cavity is analyzed.