深部大断面硐室动静载作用下锚固承载结构稳定机理研究  

Damage mechanism and support of surrounding rock anchorage structure of deep large section chamber under static-dynamic coupling loading

作　　者：宁建国 邱鹏奇 杨书浩 沈圳 李壮 王俊 NING Jianguo;QIU Pengqi;YANG Shuhao;SHEN Zhen;LI Zhuang;WANG Jun(College of Mining and Safety Engineering,Shandong University of Science and Technology,Qingdao,Shandong 266590,China)

机构地区：[1]山东科技大学矿业与安全工程学院,山东青岛266590

出　　处：《采矿与安全工程学报》2020年第1期50-61,共12页Journal of Mining & Safety Engineering

基　　金：国家重点研发计划项目(2018YFC0604703);国家自然科学基金项目(51574154);山东省重点研发计划项目(2018GSF116003);山东省自然科学基金青年基金项目(ZR2019QEE002);山东科技大学研究生科技创新项目(SDKDYC190116)。

摘　　要：针对动载扰动条件下深部大断面硐室围岩锚固支护结构稳定性差、支护设计不合理等问题,以新巨龙煤矿井下煤矸分离大断面硐室为例,采用现场调研、理论分析和室内试验等手段,研究在深部冲击应力与高围岩应力叠加构成的复杂应力环境下大断面硐室围岩锚固支护结构损伤演化特征,构建动静载荷作用下深部大断面硐室围岩锚固承载结构损伤演化模型,获得深部大断面硐室围岩锚固支护结构破坏机理并对深部大断面硐室的围岩锚固支护设计提出合理建议。结果表明:1)深部冲击应力与高围岩应力叠加是大断面硐室围岩变形破坏的主要原因,在受到强动载冲击时,深部大断面硐室顶板、两帮锚杆(索)受损严重,很容易造成顶板大面积垮塌及帮部煤体突出;2)通过室内SHPB动态冲击试验获得了动静载组合作用下,加锚试件的强度和峰后回弹斜率均随着动态应变率的增大而升高,加锚试件对动载冲击能量的耗散能占比与动态应变率呈现出正相关的特性,锚固界面(锚固剂/锚杆、锚固剂/岩体)的黏结程度在锚固体对应力波能量耗散过程中起到了关键作用;3)深部大断面硐室锚固承载结构的失稳破坏是由于动载作用下硐室围岩、锚固剂和锚杆三者之间不协同变形造成的剪切滑移及锚固体受动载压缩变形导致的。提高硐室围岩、锚固剂和锚杆的抗滑移特性,增加锚固密度提高抗压缩变形能力可有效降低动载应力波对深部大断面硐室围岩支护结构的影响。研究成果对井下永久硐室及巷道的加固工程具有一定的理论指导和借鉴意义。In view of the poor stability of anchorage support structure and the unreasonable design of support in the deep large-section chamber surrounding rock under dynamic load disturbance, with Xinjulong Coal Mine as an example, the damage evolution characteristics of anchorage support structure of large section chamber surrounding rock under complex stress environment composed of deep impact stress and high surrounding rock stress have been studied through site investigation, theoretical analysis and laboratory tests. The damage evolution model of rock with bolt support of deep large section chamber under static-dynamic coupling loading has been established. The failure mechanism of rock with bolt support of deep large section chamber surrounding rock has been obtained and thus the reasonable suggestions for the design of surrounding rock anchorage support for deep large section chamber have been put forward. The results have shown that:1) The superposition of deep impact stress and high surrounding rock stress are the main causes of deformation and failure of surrounding rock of large section chamber. When the deep large section chamber is impacted by strong dynamic load, the bolt would be seriously damaged, which easily causes large area roof collapse and coal body outburst at the side. 2) The characteristics of anchored specimens have been obtained through indoor SHPB dynamic impact tests that under static-dynamic coupling loading, the strength and post-peak rebound slope rate of anchored specimens will increase with dynamic strain rate. The energy dissipation rate of anchored specimens is positively correlated with dynamic strain rate. The viscosity of the anchoring interface(both between anchoring agent and bolt, and between anchoring agent and rock mass) plays a key role during the energy dissipation of stress wave. 3) The instability failure of the anchorage structure of deep large section chamber is caused by shear slip and the compressive deformation of anchorage body due to the uncoordinated deformation betw

关 键 词：大断面硐室 锚固承载结构 冲击破坏 相似材料模拟 动静组合加载 

分 类 号：TD322[矿业工程—矿井建设]