不同条件下巴东三中滑坡滑带土大型三轴试验分析

Analysis of Large Scale Triaxial Experiment of Sliding Zone Soil in Sanzhong Badong under Different Conditions

利用大型三轴剪切仪,研究了不同围压和不同初始干密度下巴东三中滑坡滑带土物理力学性质。试验表明,该土样在剪切破坏的整个过程中出现剪缩和应变硬化现象。通过分析试验数据,得出该粗粒土的剪切破坏与围压σ_3有着密切的关系。体积变化率ε_v与围压σ_3和初始干密度ρ_d均有关系,前者与后两者之间有着二次多项式的关系,即:ε_v=m_1(σ_3/P_a)~2+m_2(σ_3/P_a)+m_3,其中m_1,m_2,m_3均为试验参数,且均与ρd呈二次多项式关系。

By using large scale triaxial shear apparatus, the physical and mechanical properties of sliding zone soils in Sanzhong, Badong have been studied with the conditions of different confining pressures and initial dry densities. The results show that all the samples exhibit shear shrinkage and strain hardening in the whole process. The analysis of the experimental data reveals the relation between shear failure and confining pressure of this coarse-grained soil. Body-strain of the sample is related to the confining pressure and initial dry density. There is a relation of quadratic polynomial between body-strain and confining pres- sure as well as initial dry density. Finally, the specific formulas are given.