锚固方式对岩石节理宏细观剪切特性的影响及其机制研究  

Study of the effect of anchorage modes on the macro and micro shear characteristics of rock joints and its mechanism

作　　者：蒋宇静[1,2,3] 张孙豪 栾恒杰 左海峰[3] 刘光饶 李博 李鑫鹏 JIANG Yujing;ZHANG Sunhao;LUAN Hengjie;ZUO Haifeng;LIU Guangrao;LI Bo;LI Xinpeng(State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology,Shandong University of Science and Technology,Qingdao,Shandong 266590,China;Graduate School of Engineering,Nagasaki University,Nagasaki 852-8521,Japan;Academician(Expert)Workstation,Inner Mongolia Shanghaimiao Mining Co.,Ltd.,Ordos,Inner Mongolia 016299,China;College of Civil Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]山东科技大学矿山灾害预防控制省部共建国家重点实验室培育基地,山东青岛266590 [2]长崎大学工学研究科,日本长崎852-8521 [3]内蒙古上海庙矿业有限责任公司院士专家工作站,内蒙古鄂尔多斯016299 [4]同济大学土木工程学院,上海200092

出　　处：《岩石力学与工程学报》2024年第6期1301-1315,共15页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(52104093);鄂尔多斯市标志性创新团队项目(TD20232307)。

摘　　要：随着岩体工程规模的不断扩大和赋存环境的日趋复杂,岩石节理剪切滑移引起锚杆破断的现象日益突出。认清锚固节理的剪切特性及其抗剪机制对于岩体工程稳定性控制设计至关重要。通过开展锚固节理剪切试验与数值模拟,系统研究全锚和端锚2种方式对岩石节理宏细观剪切特性的影响及其机制。结果表明:全锚方式下锚固剂的存在会使锚杆迅速发挥其“销钉作用”,而端锚方式下在剪切位移超过钻孔与锚杆间的间隙后锚杆才开始发挥作用;在锚杆破断前,全锚方式相对于端锚方式的峰值剪切应力和破断剪切应力更大;相同剪切位移下相对于端锚,全锚条件下锚固节理的裂纹数量更多;全锚方式下裂纹集中在锚杆附近,尤其是锚杆与节理相交处,端锚方式下裂纹分布较为分散,在端头锚固处、锚杆与节理相交处以及垫片处均有分布;相同剪切位移条件下,全锚锚杆的剪切应力远大于端锚锚杆,但其轴向应力因受到锚固剂限制主要集中在节理面附近;端锚方式下锚杆轴向应力被充分调动,传递至垫片处后可有效增大节理的法向应力;端锚锚杆和全锚锚杆的变形范围均不断增大,但端锚锚杆的变形范围显著大于全锚锚杆。With the continuous expansion of the scale of rock mass engineering and the increasing complexity of the occurrence environment,the phenomenon of rock joint shear slip causing rock bolt breakage is becoming more and more prominent.It is very important to recognize the shear characteristics and shear mechanism of bolted joints for the stability control design of rock mass engineering.In this paper,the effects of full anchor and end anchor modes on the macro and micro shear properties of rock joints and their mechanisms are systematically studied through shear tests and numerical simulation of anchored joints.The results show that the presence of anchoring agent can make the bolt play its“pin role”quickly in the full-anchor mode,while the bolt does not play its role until the shear displacement exceeds the gap between the borehole and the bolt in the end-anchor mode.Before the anchor rod fractures,the peak shear stress and breaking shear stress in the full-anchor mode are greater compared to the end-anchor mode.Under the same shear displacement,the number of cracks in the anchored joint is more in the full-anchor condition compared to the end-anchor condition.Under full anchoring method,the cracks are concentrated near the anchor rod,especially at the intersection of the anchor rod and the joint,while under end anchoring method,the cracks are distributed in the end bolted,the intersection of the anchor rod and the joint and the gasket.Under the same shear displacement condition,the shear stress of full-anchored bolt is much greater than that of end-anchored bolt,but its axial stress is mainly concentrated near the joint surface due to the restriction of anchoring agent.The axial stress of end-anchored bolt is fully mobilized and can effectively increase the normal stress of the joint after being transferred to the gasket.After the peak shear displacement,the deformation range of end-anchored bolt and full-anchored bolt increases continuously,but the deformation range of end-anchored bolt is significantly larger

关 键 词：岩石力学 岩石节理 锚固方式 宏细观剪切特性 数值模拟 

分 类 号：TU45[建筑科学—岩土工程]