充填节理特性对岩石静态压缩力学行为影响的颗粒流模拟

Particle flow simulation of the effect of characteristics of filled joints on rock mechanical behavior under static compression

充填节理特性是影响节理岩体工程安全稳定性的重要因素。为研究充填节理特性对岩石静态压缩力学及变形特性的影响,基于充填节理岩石室内静态单轴压缩试验结果,采用颗粒流数值模拟的方法研究不同节理倾角、多条节理数以及不同节理厚度情况下充填节理岩石的力学参数变化规律、微裂纹发育状况和最终破坏形态特点。结果表明:峰值应力和弹性模量随着充填节理倾角的增大呈现出U型变化趋势、随着充填节理厚度的增加而不断降低,且弹性模量降低速度逐渐变缓。随着充填节理倾角的增大,起裂应力和微裂纹总数量出现先减小后增大的变化趋势,微裂纹总数量随着充填节理厚度的增加而不断增加。节理倾角改变会严重影响充填节理岩石微裂纹的发育状况和最终破坏形态;当节理倾角较大且含有多条充填节理时岩样会发生明显的滑移破坏,充填节理岩石整体稳定性较差、破坏程度严重。

The characteristics of filled joints are important factors affecting the stability of rock engineering.To study the influence of the characteristics of filled joints on the statically compressive mechanics and deforming features of rock,based on laboratory uniaxial tests of rock samples with filled joints,we performed particle flow simulations to study the evolutions of mechanical parameters,micro-crack development,and the final failure morphology characteristics considering the variety of angles,numbers,and thicknesses of filled joints.The results show that the peak strength and elastic modulus display a U-shaped variation with the increase of the angle of joints,monotonically decrease with the thickness of joints and the decreasing speed of elastic modulus gradually slows down.The crack initiation stress and the total number of micro-cracks decrease first and then increase with the joint angle,and the total number of micro-cracks increases with the increase of joint thickness.The change of joint angle seriously affects the development of micro-cracks and the final failure mode of rock,i.e.,when the joint angle is large,particularly with multiple joints,the overall stability of samples is poor,and samples are vulnerable to suffering sliding failure and cause serious damages.