隧道施工中环境土层工程性质研究

RESEARCH ON ENGINEERING PROPERTIES OF SOIL LAYER IN TUNNEL CONSTRUCTION

利用非饱和土的三轴仪 ,测定不同吸力状态下的土的强度特性 ,并确立了两者之间的定量关系 ,同时进行了含水量对非饱和土的强度影响试验 ,研究了北京地区的非饱和土的强度特性。试验结果表明 :不同的吸力状态下 ,土的强度明显提高 ;含水量的改变对内聚力有明显影响 ,而对内摩擦角无明显影响 。

The strength characteristics of the unsaturated soil in Beijing area were determined by using unsaturated triaxial apparatus at different matric suctions and a quantitatire relation between strength and matric suction was established. At the same time, we carried out a test of influence water content on the strength of the unsaturated soil. The result shows that the strength is raised at the different matric suctions and the change of water content obviously influences the cohesive force, but not remarkably influences the internal friction angle. We measured the turning point of water content to the strength changes of these specimens too.