Abstract:

The effects of different initial stress states on the constitutive relations of clay are studied. With clay selected as test sample, two series of triaxial consolidation draining compression tests are performed under different consolidation conditions, isotropic consolidation and K0 consolidation. Based on the tests under the two different initial consolidation conditions, the elastoplastic constitutive models which contain two yield surfaces of two relatively independent hardening parameters and are derived by using numerical modeling method. The three-dimensional surfaces of the stress-strain relations in the whole stress field are drawn through visualization. Moreover, the comparisons of the stress-strain relation curves with the simulated results obtained by the numerical model, Cam-clay model, Duncan-Chang hyperbolic model and from test data are made. It is shown that the numerical modeling method is reasonable, which can reflect the effects of stress paths and stress history.

Key words: numerical modeling method, stress path, stress history, constitutive relation, clay