Study on Engineering Characteristics of Coarse-Grained Soil based on Large-Scale Triaxial Test

摘要

Using large-scale shearing device, isotropiclly consolidated-drained triaxial test under different confining pressures are performed for overburden material of ShuangJiangKou earthdam which relative density is 0.9. The engineering characteristics of coarse-grained soil such as strength and deformation is studied. The results show the peak strength of coarse-grained soil under isotropically increase with the confining pressure and there is a relationship of linear between the peak strength of coarse-grained soil and initial modulus. The volume strain value of isotropically consolidated-drained triaxial shear test increase with increase of confining pressure, and the dilatancy decrease increase with increase of confining pressure. The secant modulus E_(sl) and the tangent modulus E_(tl) obtained by the tests both increase with increase with increase of confining pressure, and the values of E_(sl)/E_i and E_(tl)/E_i are all smaller than one. The failure poisson ratio v_(if) obtained by the tests both decrease with increase with increase of confining pressure, and there is a relationship of power function between vif and σ_3/P_a.