摘要
为研究锚杆对深部含裂隙岩体的锚固止裂效应,进行了不同冲击气压下的动静组合加载试验.基于优化的锚杆界面力学模型,建立了新型有限差分法-离散元法(FDM-DEM)耦合数值分离式霍普金森杆系统及锚杆模型.对裂隙岩体和锚固裂隙岩体的力学特性、能量耗散及破坏特征进行了研究,并从细观能量耗散角度阐述了锚杆在动荷载下对裂隙岩体的锚固机理.结果表明:裂隙岩体和锚固裂隙岩体的动态抗压强度随冲击气压的增大而增加,锚杆对裂隙岩体的锚固效应可提高动态抗压强度,减小裂隙岩体的冲击后破坏程度,锚固裂隙岩体能量吸收率变化规律趋同于完整岩体;从细观角度分析,锚杆加固使得裂隙岩体的摩擦滑移耗散能和破坏后碎块携带动能降低,整体吸收能量减少.
To investigate the crack-arresting effect of rock bolts on fractured deep rock masses,dynamic-static combined loading tests were conducted under varying impact air pressures.Based on an optimized mechanical model of the bolt-rock interface,a new finite difference method-discrete element method(FDM-DEM)coupled numerical split Hopkinson pressure bar(SHPB)system and bolt model were developed.The mechanical properties,energy dissipation,and failure characteristics of both fractured rock masses and bolted fractured rock masses were studied.Furthermore,the anchoring mechanism of rock bolts under dynamic loads was evaluated from the perspective of mesoscale energy dissipation for fractured rock masses.The results indicate that the dynamic compressive strengths of fractured rock masses and bolted fractured rock masses increase with higher impact air pressures.The anchoring effect of rock bolts for fractured rock masses enhances the dynamic compressive strength and reduces the post-impact damage.The energy absorptivity of bolted fractured rock masses is similar to that of intact rock masses.From a mesoscale perspective,bolt reinforcement reduces the frictional slip dissipation energy and the kinetic energy carried by fragments post-failure in fractured rock masses,leading to an overall decrease in absorbed energy.
作者
韩凤岩
余东峰
陈瑜
黄林冲
徐志胜
Han Fengyan;Yu Dongfeng;Chen Yu;Huang Linchong;Xu Zhisheng(School of Civil Engineering,Central South University,Changsha 410075,China;State Key Laboratory for Tunnel Engineering,Guangzhou 510275,China;Guangdong Key Laboratory of Marine Civil Engineering,Sun Yat-sen University,Guangzhou 510275,China)
出处
《东南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2024年第6期1418-1424,共7页
Journal of Southeast University：Natural Science Edition
基金
国家自然科学基金资助项目(52174101)。
关键词
动静组合加载
裂隙岩石
力学特性
锚固机理
有限差分法-离散元法(FDM-DEM)耦合
dynamic and static combined loading
fractured rock
mechanical properties
anchoring mechanism
finite difference method-discrete element method(FDM-DEM)coupling
