粘性土应力路径试验

Stress path tests of cohesive soil

利用GDS多功能三轴仪,对南京河西地区原状粘性土进行了常规三轴压缩、减压三轴压缩和等p应力路径的固结不排水三轴试验,探讨不同应力路径下粘性土的变形和强度特性。实验表明:不同应力路径下土的应力应变关系都呈曲线形态相似的非线性应变硬化型,而土的峰值强度和土中孔隙水压力差异明显;相同应力路径试验得到的有效应力路径形态一致,常规三轴压缩试验中有效应力路径呈S形。

Deformation and strengthening behaviors of cohesive soil at the west area of Nanjing city were investigated by using GDS triaxial instrument, the triaxial tests were carried out under consolidated undrained condition with different stress paths, which include conventional triaxial compression, reduced triaxial compression and with constant p. The results show that the response of stress-strain is nonlinear hardening, the peak strength and the pore pressure are obviously different in different stress pathes. The shape of effective stress path is similar under the same stress path testing, the S＇ shape of effective stress path was observed in conventional triaxial compression test.