不同形貌节理对应力波传播影响的数值模拟

用3DEC离散元软件对一维正弦纵波在无节理有限长及有一节理有限长岩杆中的传播进行标定,确定建模的单元网格尺寸、边界条件等参数。然后对一维正弦纵波在含量化的不同粗糙度节理面的岩杆中传播进行数值模拟,探究应力波穿过不同形貌特征的节理时的透反射规律。分析模拟结果发现:节理面粗糙度JRC值相同,相对节理初始法向刚度不同时,随着刚度系数的增加,透射过节理面的应力波越多,在α0.5时,透射系数值增加较快;在α0.5时,透射系数值增加较慢,逐渐趋近于1。同一刚度系数α值下,随着节理粗糙度JRC值的增加,透射系数增大,当α1.5时,透射系数趋于稳定。

Numerical Simulation on Influence of Different Topography Joints on Stress Wave Propagation

The discrete element software 3DEC is used to calibrate the propagation of one-dimensional sine longitudinal wave in a limited length rock bar without joints or with one joints,and the element mesh sizes,boundary conditions and other parameters are determined.The propagation of one-dimensional sine longitudinal wave in rock bar with different quantified roughness joints is simulated to study rules of transmission and reflection of stress wave across different topography joints.The results show that,when joint roughness constant is same and joint initial normal stiffness constant is various,transmission of stress wave across joints increase with the stiffness constant.When α<0.5,the transmission constant increases fast;when α>0.5,the transmission constant increases slow,finally approaches to 1.When stiffness constant is same,transmission of stress wave increases with the joint roughness constant,when α>1.5,the transmission constant approaches to a certain value.