Study on the Constitutive Model of Marble Based on the Conventional Triaxial Compression Test

摘要

The RMB-150B rock mechanics test system was employed to obtain the complete stress-strain test curves under confining pressures of 0-30MPa for marble samples from Ya'an ,Sichuan province. On the basis of former study and the convention triaxial pressure test results ,the complete procedures curves which described the relationships between yielding strength、 peak strength、 residual strength and confining pressure was obtained. Taking the strain softening of rock into account, the bilinear elastic-linear softening-residual perfect plasticity four-linear model was put forward in this paper on the basis of the test results and theory of plasticity. This model was adopted to describe the behaviors of marble in different phases under triaxial compression with the constitutive equation of strain softening phase as focus. The results indicated that the theoretic model fitted in well with the test results.