不同应力路径下饱和粉土强度与变形特性试验研究

为了模拟地下工程施工过程中不同位置处受扰动土体实际的应力和变形状态,探讨不同应力路径条件下土体的强度和变形破坏特性,共进行了4组试验,分别为常规三轴压缩试验、等 P 压缩试验、等压固结减压压缩试验和偏压固结减压压缩试验。试验结果表明在不同的剪切路径下土体表现出不同的强度与变形特征,即在常规压缩条件下强度最高,减压压缩条件下的强度最低。而且,常规三轴压缩、等P压缩和减压压缩这3种剪切方式下土体均没有出现应变软化现象。试验结果所揭示的规律可为现场施工提供科学有益的指导。

Deformation and Strength Characters of Saturated Silty Soil under Different Stress Paths

In order to simulate the actual stress and deformation state of disturbed soil at different positions of under-ground engineering construction, we designed four test groups to explore the strength and deformation characteristics of soil under different stress paths. The four tests are conventional triaxial compression test, compression test with equal P, isotropic consolidation decompressed compression test, and anisotropic consolidation decompressed compression test. Experimental results show that the soil exhibits different strength and deformation characteristics under different shear paths. In conventional compression condition the strength is the highest, whereas in decompression condition the strength is the lowest. Moreover, strain softening did not appear under the three different shear paths.