RESEARCH ON MECHANICAL CHARACTERISTIC OF THE SOIL ROCK MIXTURES BY LARGE-SCALE TRIAXIAL SHEAR TESTS

Taking the remolded sample of soil rock mixtures as research objective, Consolidated undrained(CU)triaxial shear tests were performed to study the effect of volumetric block proportions(VBP) and confining pressures on mechanical behaviors of soil rock mixtures by using large-scale triaxial shear apparatus, the trends of the initial shear stiffness and shear strength of soil rock mixtures under different volumetric block proportions(VBP) and different confining pressure conditions are analyzed. The results show that: the degeneration failure mode of soil rock mixtures is different from conventional rock and soil mass, stress jump exists in the curve of stress-strain relationship, and the degeneration failure mode of soil rock mixtures is different between each other under different volumetric block proportions(VBP) and different confining pressure conditions. The Shear strength of soil rock mixtures increases with the increase of confining pressure, however, it increases initially then decrease with the the increase of the volumetric block proportions(VBP),when the confining pressure doubled, the trends of shear strength of soil rock mixtures is different at different levels of confining pressure; the initial shear stiffness of soil rock mixtures increases with the increase of confining pressure, and it increases initially then decrease with the the increase of the volumetric block proportions(VBP),when the confining pressure doubled, the trends of initial shear stiffness in accordance with the trends of shear strength.