岩土三轴试验中的粘聚力与内摩擦角  

The cohesive strength and the friction angle in rock-soil triaxial rests

作　　者：杨同[1] 徐川[2] 王宝学[1] 张磊[1] 廖国华[1] 

机构地区：[1]北京科技大学"金属矿山高效开采及安全"教育部重点实验室,北京100083 [2]北京大学微电子研究院,北京100871

出　　处：《中国矿业》2007年第12期104-107,共4页China Mining Magazine

摘　　要：根据莫尔-库仑破坏准则,岩土三轴试验的轴向破坏应力与围压之间呈线性关系。根据包络线定理,通过求解三轴试验应力圆包络线,得到粘聚力c、内摩擦角φ的计算公式。该公式具有物理意义明确,表述简单,且c、φ值可分别独立计算等特点,开辟了抗剪强度参数计算的新途径。据分析,粘聚力c与σc(零围压时的轴向破坏应力)成正比,随K(轴向破坏应力随围压变化的斜率)增大而下降;内摩擦角φ只随K增大单调升高。应用该公式列出了多组岩土工程中有一定代表性的岩土三轴试验数据。According to Mohr-Coulomb failure criterion, the axial stress at failure in rock-soil triaxial tests is in linear relationship with the lateral stress. In this article, a group of formulae to calculate the cohesive strength c and the friction angle φ from rock-soil triaxial tests is obtained by solving the stress circle＇ s envelope. The formulae have clear physical meanings and convenient applications. In addition, c and φ values can be respectively calculated by using such formulae so that another way to calculate shear strength parameters is proposed. According to the analysis, the cohesive strength c is proportional to σc （the axial stress at failure when lateral stress is zero）, and decreases when K （the slope of the axial stress at failure versus lateral stress） increases; the friction angle φ increases with K. Using the formulae, rock-soil triaxial test data, which are representative in rock-soil engineering domain, are listed in this article.

关 键 词：岩土三轴试验 抗剪强度 粘聚力 内摩擦角 包络线 

分 类 号：TU411[建筑科学—岩土工程] TU459[建筑科学—土工工程]