摘要
为分析隧道支护结构作用机制及其在层状和软弱岩体隧道中的支护特性,通过室内物理模拟试验和现场测试,研究普通螺纹锚杆和钢花管锚固下的岩石在单轴压缩试验下的力学、变形特性及其现场支护特性。试验结果表明:(1)锚杆主要通过改善围岩的受力状态和提高围岩强度2个方面来实现其锚固作用,并且锚杆对锚固体围岩强度参数的提高主要表现为预紧力的压缩带作用、锚固剂对围岩损伤的修复作用和锚杆杆体对锚固体整体强度和密度的增强作用3个方面。(2)通过对试验后的加锚试件进行CT扫描发现,锚杆对裂纹的止裂作用是锚固区对裂纹的弱化、剪段、止裂的结果,其止裂效果与锚固区范围大小有关,锚固区范围越大,止裂效果越好。(3)由于药卷锚杆和钢花管的锚固特性不同,药卷锚杆能够很好地锚固岩性一般的层状页岩隧道,而具有注浆功能的钢花管更适用于岩性较差的软弱破碎岩体。
In order to analyze the action mechanism of tunnel support structure and its supporting characteristics in layered and weak rock tunnel,indoor physical simulation test and steel-concrete composite beam of the three point bending tests were conducted successively,and the mechanical and deformation characteristics of common screw bolt and steel pipe anchorage of rock under uniaxial compression tests and the steel arch bending performance were researched. The test results show that,the bolt mainly achieves the anchoring effect by improving the stress state of surrounding rock and improving the strength of surrounding rock,and also the improvement of strength to anchorage surrounding rock is mainly the effect of compression zone of pre stress,the repairing effect of anchorage agent on surrounding rock and the strengthening effect of anchor rod on the whole strength and density of anchor. Through the CT scanning of the anchor specimens after the test,it is found that the crack arresting effect of the anchor on the crack is the result of the weakening,shear and stop of the crack in the anchorage zone,and the crack arrest effect is related to the size of anchorage zone. The larger the anchorage zone is,the better the crack arrest effect is. According to the different characteristics of bolt and anchor roll steel pipes,explosive bolts can anchorage layered shale tunnel lithology good,while the function of grouting steel pipe is more suitable for the poor lithology of the soft fractured rock mass.
作者
腾俊洋
唐建新
陈宇龙
张宇宁
TENG Junyang;TANG Jianxin;CHEN Yulong;ZHANG Yuning(State Key Laboratory of Coal Mine Disaster Dynamics and Control,Chongqing University,Chongqing 400044,China;College of Resources and Environmental Sciences,Chongqing University,Chongqing 400044,China;State Key Laboratory of Hydroscience and Engineering,Tsinghua University,Beijing 100084,China;School of Civil and Architectural Engineering, Yangtze Normal University,Chongqing 408100,China)
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2018年第A02期4221-4233,共13页
Chinese Journal of Rock Mechanics and Engineering
基金
重庆大学煤矿灾害动力学与控制国家重点实验室自主课题重点项目(2011DA105287–ZD201504)~~
关键词
隧道工程
支护结构
加锚试验
支护机制
现场测试
tunnel engineering
support structure
anchor test
support mechanism
field test
