锚杆岩体界面载荷传递规律及锚固长度设计  

Load transfer law and anchorage length design at interface between rock bolts and rock mass

作　　者：赵同彬[1,2] 李龙飞 邢明录 张玉宝[1,2] 王学斌[1] ZHAO Tongbin;LI Longfei;XING Minglu;ZHANG Yubao;WANG Xuebin(College of Energy and Mining Engineering,Shandong University of Science and Technology,Qingdao 266590,China;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 266590,China)

机构地区：[1]山东科技大学能源与矿业工程学院,山东青岛266590 [2]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

出　　处：《山东科技大学学报（自然科学版）》2024年第2期1-12,共12页Journal of Shandong University of Science and Technology(Natural Science)

基　　金：国家自然科学基金项目(52374097,52104137);山东省泰山学者工程项目(tstp20221126)。

摘　　要：为揭示巷道围岩锚固界面脱粘失效机理,量化锚杆支护设计参数,采用三线性粘结滑移模型进行理论分析,对轴向载荷作用下锚固脱粘失效全过程中,锚固段界面剪应力、锚杆轴力分布演化规律以及界面极限锚固力进行研究,根据锚固段长度不同,得到两种界面剪应力分布演化类型。研究结果表明:当锚固长度较短时,界面剪应力存在全长软化阶段;当锚固长度较长时,界面剪应力存在弹性-软化-滑移三段共存阶段。锚固粘结界面弹性段、软化段、摩擦段内的剪应力分别呈现双曲余弦函数衰减分布、余弦函数上升分布、均匀分布规律,锚杆轴力随界面剪应力分布演化呈现多种形态的衰减分布规律。根据锚固界面模型解析计算获得极限锚固力,当不考虑脱粘摩擦力时,极限锚固力随锚固长度的增加趋近于某一固定值;当考虑脱粘摩擦力时,增加锚固长度能够持续提高锚固界面安全系数。研究成果可为锚固机制分析、锚杆支护参数设计提供理论参考。To reveal the failure mechanism of anchorage interface debonding of surrounding rock in roadway and quantify the design parameters of rock bolt support,theoretical derivation was made by using the trilinear bond-slip model,and the distribution and evolution law of interfacial shear stress,axial force of bolt and ultimate anchorage force at the interface during the whole process of anchorage debonding failure under axial load were studied.According to the different lengths of anchorage section,two types of interfacial shear stress distribution and evolution were obtained.The results show that when the anchorage length is short,the interfacial shear stress has a full-length softening stage and when the anchorage length is long,the interfacial shear stress has an elastic-softening-sliding coexistence stage.The shear stress in the elastic,softening and friction sections of the anchorage bonding interface shows different distribution laws,that is,hyperbolic cosine function attenuation,cosine function rise and uniform distribution respectively.The axial force of the rock bolt shows various attenuation distribution laws with the distribution and evolution of the interfacial shear stress.According to the analytical calculation of the anchorage interface model,the ultimate anchorage force approaches a fixed value with the increase of anchorage length when the debonding friction force is not considered.When the debonding friction force is considered,increasing anchorage length can continuously improve the safety factor of anchorage interface.The research results can provide theoretical reference for the analysis of anchoring mechanism and the design of rock bolt support parameters.

关 键 词：锚固界面 粘结滑移模型 剪应力分布 极限锚固力 锚固长度 

分 类 号：TD315[矿业工程—矿井建设]