开挖扰动下巷道围岩细观力学行为分析

Mesomechanics Behavior Analysis of Surrounding Rock Under Roadway Excavation Disturbance

为研究巷道在开挖扰动下围岩的细观力学行为,采用颗粒流软件建立开挖模型,分析巷道在开挖扰动下围岩的应力和位移分布规律。研究结果表明:在巷道的左右底角处容易出现局部应力集中,在两帮和顶底处压应力比较小容易形成拉裂破坏。同时分析了颗粒黏结强度对巷道顶板下沉量的影响,随着颗粒黏结强度的不同,下沉量呈现出类似于幂函数分布规律,通过增加围岩的黏结强度能够提高围岩的自承能力,减小围岩变形,所以在工程应用中可以通过注浆等方法来提高围岩的黏结强度达到围岩稳定的效果。

To study the mesomechanics behavior of surrounding rock under excavation disturbance,the excavation model is established by using PFC software,and the distribution law of stress and displacement is analyzed.The results show that the local stress concentration easily arises near the two bottom corners of the chamber; for the small compressive stress near the two sides and top-bottom of the roadway,the tension failure is easily formed.And at the same time,the influence of the particles bonding strength on the sinkage of roadway roof is analyzed.The law of the sinkage is similar to the power function distribution; the surrounding rock bearing capacity can be improved by increasing the compressive strength of the surrounding rock,then the deformation of surrounding rock can be reduced.So,in engineering application,the grouting method is used to improve the surrounding rock compressive strength to achieve the surrounding rock stability effect.