加载角度对弧形加载巴西劈裂试验影响的数值研究  

Numerical Study on the Influence of Loading Angle on Brazilian Splitting Test under Arc Loading

作　　者：孙志伟 包春燕 蔡悦翔[1] SUN Zhiwei;BAO Chunyan;CAI Yuexiang(School of Civil Engineering,Shaoxing University,Shaoxing 312000,China;Experimental Center of Rock Mechanics and Geohazards,Shaoxing University,Shaoxing 312000,China)

机构地区：[1]绍兴文理学院土木工程学院,绍兴312000 [2]绍兴文理学院岩石力学与地质灾害实验中心,绍兴312000

出　　处：《结构工程师》2022年第1期39-46,共8页Structural Engineers

基　　金：国家自然科学基金青年项目(41801043)。

摘　　要：巴西劈裂试验具有试件加工方便、试验易于实现等优点,是测试岩石抗拉强度的主要方法,但是相关规范没有对加载角度作出限定,导致试验的结果较为离散。为研究加载角度对巴西劈裂试验的影响,利用有限元软件ANSYS建立加载角度为0°的集中加载模型,计算得到的应力数值解与理论解误差较小,证明数值模拟的有效性;之后以集中加载模型为原型分别建立不同加载角度的弧形加载模型,分析加载角度对中轴线上应力分布和圆盘破坏模式的影响。结果表明:随着加载角度的增大,圆盘中心处的水平拉应力减小,压拉应力比增加速率加快,圆盘内的最大压拉应力比减小。推荐弧形加载巴西劈裂试验的加载角度范围为18.4°~27.8°,对应的抗拉强度修正系数范围为0.951~0.974。The Brazilian splitting test is a main method to test the tensile strength of rock with the advantages of convenient specimen processing and easy test implementation.However,the loading angle is not limited in relevant codes,which leads to the discrete test results.In order to study the influence of loading angle on Brazilian splitting test,the finite element software ANSYS was used to establish a concentrated loading model with loading angle of 0°and the error between the calculated stress numerical solution and the theoretical solution was small,which proved the validity of the numerical simulation.Then,the arc loading models with different loading angles were established based on the centralized loading model,and the stress on the central axis was analyzed distribution and disk failure mode.The results show that with the increase of loading angle,the horizontal tensile stress at the center of the disc decreases,the increasing rate of compressive tensile stress ratio accelerates,and the maximum compressive tensile stress ratio decreases.The recommended loading angle range of Brazilian splitting test under arc loading is 18.4°to 27.8°and the corresponding correction coefficient of tensile strength is 0.951~0.974.

关 键 词：抗拉强度 巴西圆盘劈裂试验 弧形加载 加载角度 数值模拟 

分 类 号：TU45[建筑科学—岩土工程]