Influence factor on dilatancy of coarse-grained soil based on large-scale triaxial test

Using large-scale shearing device, K-0 consolidated-drained triaxial test and isotropiclly consolidated-drained triaxial test under different confining pressures are performed for overburden material of ShuangJiangKou earth dam which relative density is 0.9. And meanwhile, isotropically consolidated-drained triaxial test under different confining pressures are also performed for overburden material of ShuangJiangKou earth dam which relative density is 0.8. The difference of strength and deformation between under under K-0-consolidation condition and isotropic consolidation condition and between under different relative density, and the influence of confining pressure, relative density and consolidation condition on the dilatancy of coarse-grained are analyzed. The results show that the strength of K-0 consolidated-drained triaxial shear test is slight greater than that obtained by isotropically consolidated-drained test. The strength of coarse-grained soil increases with increase of relative density. The volume strain value of isotropically consolidated-drained triaxial shear test is bigger than that of K(0)0 consolidated-drained test, and the volume strain value decreases with the decreases of relative density. The dilatancy of coarse-grained soil decreases with the increase of confining pressure, and increases with the increase of static lateral pressure coefficient.