山区公路路基填料大型三轴试验研究

Large-Scale Triaxial Test for Highway Subgrade Filling in Moutainous Area

通过大型三轴试验,对粗粒料的力学特性进行了研究。结果表明:初始密度相同时应力-应变关系曲线与围压有关,低围压下表现为弱应变软化型,高围压下表现为应变硬化型;低围压下,粗粒料在剪切过程中先剪胀后剪缩,随着围压增大,体变表现为剪缩,但体缩率逐渐减小并趋于稳定;粗粒料在剪切过程中具有表观凝聚力,内摩擦角随围压增大而减小。

The machnical properties of coarse grained soil are studied via large-scale triaxial test. The results indicate that the pattern of stress-strain curve relates to the confining pressure when the the filling with same density. At low pressure, strain softening is observed and strain-hardening is observed at high pressure. The coarse grained soil shows shear dilatiation before shear contraction in the process of shear at low confining pressure. With the pressure increases, coarse grained soil shows shear contraction, while the rate of constraction decreases tends to be stability. The coarse grained soils has apparent cohe- sion in the process of shear, the internal friction angle decreases with the increase of pressure.