动荷载作用下深部巷道围岩动态应力分布规律及能量演化特征  

Dynamic stress distribution and energy evolution characteristics ofdeep roadway surrounding rock under dynamic loads

作　　者：孙海玉 黄伟洪 范东芳 SUN Hai-yu;HUANG Wei-hong;FAN Dong-fang(Zhuhai Construction Engineering Holding Group Co.,Ltd.,Zhuhai 519000,China;School of Civil Engineering,Sun Yat-Sen University,Guangzhou 510275,China;Foshan Rail Transit Design and Research Institute Co.,Ltd.,Foshan 528315,China)

机构地区：[1]珠海建工控股集团有限公司,广东珠海519000 [2]中山大学土木工程学院,广东广州510275 [3]佛山轨道交通设计研究院有限公司,广东佛山528315

出　　处：《煤炭科技》2024年第2期50-57,63,共9页Coal Science & Technology Magazine

摘　　要：巷道开挖后,围岩地应力集中分布和外界动荷载扰动是影响巷道安全稳定的2个重要因素。基于有限模型和LS-DYNA的隐—显式计算功能,分析了初始应力分别为10、30、50 MPa的岩体巷道在动荷载作用下的力学响应,获得了巷道围岩动态应力分布、能量变化及演化规律和动态变形损伤特征。研究结果表明,动荷载作用下,动态压应力集中主要分布在巷道顶部和底角附近,动态拉应力集中主要分布巷道两帮;压应力集中程度随初始应力的增大而减小,拉应力集中区域无明显变化;动载入射侧围岩质点位移和振动速度始终大于透射侧;随着初始应力的增大,围岩质点位移增大,振动速度减小;动荷载会引起围岩起初始应变能释放,岩石的应变能密度降低;巷道围岩的动态损伤总是从巷道顶部附近开始,且围岩损伤程度和范围都会随初始应力的增加而增大。After excavation of the roadway,the concentrated distribution of the in-situ stress in the surrounding rock and the disturbance of the external dynamic load are two important factors that affect the safety and stability of the roadway.Based on the finite element model and the implicit-explicit computing function of LS-DYNA,the mechanical response of the rock roadway with initial stress of 10,30 and 50 MPa under the action of dynamic load were analyzed.The dynamic stress distribution,energy change and evolution law,as well as dynamic deformation and damage characteristics of the surrounding rock of the roadway were obtained.Results show that the dynamic compressive stress concentration mainly distributes near the top and bottom corners of the roadway under the action of dynamic load,and while dynamic tensile stress concentration is mainly distributed on both sides of the roadway.The compressive stress concentration degree decreases with the increase of the initial stress,and there is no obvious change in the tensile stress concentration areas.Particle displacement and vibration velocity of the surrounding rock on the incident side of dynamic load are always higher than those on the transmission side.As the initial stress increases,the displacement of surrounding rock particles increases and the vibration velocity decreases.The dynamic load can cause initial strain energy of surrounding rock to be released,and the strain energy density of the rock decreases.The dynamic damage of surrounding rock always starts near the top of the roadway,and the damage level and areas increase with the increase of the initial stress.

关 键 词：初始应力 动态应力分布 能量演化 数值模拟 

分 类 号：TD32[矿业工程—矿井建设]