原位测定土层抗剪强度的试验研究  

Study on shear strength of soil in situ determination

作　　者：易伟欣[1] 王恩营[1] 

机构地区：[1]河南理工大学资源环境学院,河南焦作454003

出　　处：《中国矿业大学学报》2015年第4期637-643,共7页Journal of China University of Mining & Technology

基　　金：国家自然科学基金项目(10972158)

摘　　要：为了求得稍微坚硬地基土或边坡土的内摩擦角φ、黏聚力c,对十字板剪切试验装置进行了板头的改进,设计了一种新的原位获取土的内摩擦角、黏聚力的试验方法.研究了新十字板剪切试验的试验原理,得出内摩擦角、黏聚力的计算公式与方法.把新十字板剪切试验分别与圆锥动力触探试验、三轴压缩试验进行对比,对试验数据进行了统计、回归拟合分析.结果表明:新十字板剪切试验装置可顺利贯入一定深度的常见边坡、稍微坚硬地基土层中求取土的内摩擦角、黏聚力值,试验方法可行;通过对原位试验测定数据进行直线回归拟合得出的c与tanφ相关系数为0.917 8;新十字板剪切试验初始扭矩与三轴压缩试验c之间的拟合相关指数较大(0.926 2);新十字板剪切试验近似式倾斜度与三轴压缩试验tanφ之间的拟合相关指数较小(0.326 5),与试样的含水状态有很大关系.In order to calculate the internal friction angleφand cohesive strength c on little hard foundation soil or slope soil,the plate head of the vane shear test equipment was improved,and a new test method of internal friction angle and cohesive strength in situ was designed.Furthermore,the principle of the new vane shear test was studied,and the calculating formula and method were obtained.The new vane shear test was compared with conic dynamic sounding test and triaxial compression test,and the test data was analyzed and regressed fitting.The results show that the new test equipment can drill smoothly into certain depth of little hard foundation soil or slope soil,internal friction angle,cohesive strength could be obtained on original point.It indicated that the new test method was feasible.The correlation coefficient of tanφand cohesive strength cthat was obtained by linear regression fitting was 0.917 8.The correlation exponent of initial torque of new vane shear test and cohesive strength c of triaxial compression test was big of 0.926 2.The correlation exponent of the approximate gradient of the new vane shear test and tanφof triaxial compression test was small of 0.3265,which had a great deal to do with the state of water contained in samples.

关 键 词：十字板剪切试验 试验原理 试验方法 内摩擦角 黏聚力 

分 类 号：TU411.7[建筑科学—岩土工程]