JRC-JCS模型与直剪试验对比研究

 结构面抗剪强度是影响工程岩体稳定的重要因素，它决定工程岩体破坏的可能性。基于结构面粗糙度系数定向统计测量技术的JRC-JCS模型可以考虑地质和环境因素的影响，具有费用低、速度快、简便易行等特点，是获取工程岩体无填充或少填充硬岩结构面抗剪强度参数的实用方法，已为50多个岩体工程提供了结构面抗剪强度参数。为分析JRC-JCS模型评价结构面抗剪强度参数的可靠性，选取天然岩石结构面试样，进行干燥状态和饱和状态结构面抗剪强度直剪试验和JRC-JCS模型评价的对比研究。结果表明，在结构面粗糙度系数的定向统计测量、尺寸效应分析，以及剪切过程衰减折减的基础上，运用结构面粗糙度系数定向统计测量技术的JRC-JCS模型评价的结构面抗剪强度参数与直剪试验结果具有较好的一致性，JRC-JCS模型对结构面峰值摩擦角有较好的预测能力。

COMPARISON STUDY OF JRC-JCS MODEL AND DIRECT SHEAR TEST

Shear strength of structural plane has an important influence on stability of engineering rock mass. It determines the probability of engineering rock mass failure. JRC-JCS model based on directional statistical measurement technology of roughness coefficient of structural plane can consider the effect of geology and environment. For structural planes with few filling or without filling，JRC-JCS model with advantages of low cost，fast estimation and easy manipulation can provide a practical method to obtain the shear strength parameters of structural plane in hard rocks. The model has been applied to fifty rock projects in order to get the shear strength parameters of structural planes. To analyze the reliability of estimating the shear strength parameters of structural planes with JRC-JCS model，the shear strengths of natural rocks with structural plane under dry and saturated conditions are measured by direct shear test and empirical estimation with JRC-JCS model. Then，the test results of shear strength are compared. The results show that the shear strength parameters estimated by JRC-JCS model and direct shear test agree well with each other on the basis of the directional statistical measurement，the analysis of JRC scale effect and the consideration of reduced JRC during the course of shear；and JRC-JCS model can estimate the peak friction angle of structural plane well.