节理接触面积和厚度对应力波传播特性影响的颗粒流数值模拟

Numerical Simulation of Particle Flow of Stress Wave Propagation Characteristics Under the Impacts of Joint Contact Area and Thickness

节理最重要的两个参数是接触面积和厚度,应用PFC2D颗粒流软件开展了节理岩体动力特性的数值模拟,研究了节理接触面积和节理厚度对应力波传播特性的影响。通过比较模拟参数和实际参数证实PFC2D有能力模拟应力波的传播特性。然后考虑到纵波在无节理情况下也存在衰减,进行了模拟分析。最后将模型分成两组节理厚度,每组都有不同的节理接触宽度比例。最终通过对颗粒流模型的计算分析得出:无节理情况下纵波在各向同性岩体中存在线性衰减特性;节理的接触宽度比例的减少会使纵波的传播率减少;节理的厚度越大,纵波的传播率越小。

The two most important parameters of joint are contact area and thickness,therefore this paper adopted PFC2D particle flow software to develop the numerical simulation model to analyze the effects of joint contact area and joint thick-ness on propagation of stress wave.It has been proved that the PFC2D is competent in simulating the propagation law of stress wave according to compare between simulation parameters and actual parameters,after which by considering the at-tenuation of longitudinal wave in the absence of joint,simulation analysis is carried out.Finally the model is divided into two sets of joint thickness,and each group has different joint contact width ratio,through the calculation and analysis of the particle flow model it shows that linear attenuation characteristics of longitudinal waves existed in isotropic rock mass without joint and the decrease of the ratio of joints contact width will reduce the propagation rate of longitudinal wave,the greater the thickness of the joint,the smaller the propagation rate of the longitudinal wave is.