软弱破碎岩体中锚杆抗拔受力机理及试验研究  

Study on the Pullout Mechanism of Anchor Bolt in Weak and Fractured Rock Mass and Its Model Test

作　　者：徐前卫[1,2] 朱合华[2] 金方方[3] 马静[3] 明娟[3] 

机构地区：[1]同济大学道路与交通工程教育部重点实验室,上海200092 [2]同济大学岩土及地下工程教育部重点实验室,上海200092 [3]上海理工大学土木工程系,上海200093

出　　处：《地下空间与工程学报》2011年第5期830-835,共6页Chinese Journal of Underground Space and Engineering

基　　金：国家自然科学基金资助项目(41130751);教育部岩土及地下工程重点实验室(同济大学)开放实验基金资助项目

摘　　要：为深入了解锚杆的锚固机理及其在软弱破碎围岩中的加固效果,开展了一系列针对不同材质、不同锚固刻距的锚杆抗拔力试验。通过对试验结果的分析和研究,得出了如下结论:在软弱破碎围岩中,锚杆的失效主要是灌浆体与岩土体之间的剪切破坏所致;当外荷载较小时,锚杆、灌浆体和岩土体协同受力,但当荷载增大到一定程度后,锚固体与岩体之间就会进入剪切屈服状态,并在达到峰值强度后破坏;锚杆体的线性刚度值越大,对应的抗拔力也就越大;在模型试验中,合理选择锚杆的线性刚度和间距对于准确模拟锚杆的锚固效果至关重要。To understand the anchoring mechanism of rock bolt and its reinforcement effect in weak and fractured rock mass,a series of pullout model tests with different materials and groove spaces of bolt were carried out.Based on the laboratory experiments,the following conclusions can be drawn.In weak and fractured rock mass,the invalidation of anchor bolt is mainly due to the shear failure between grout filling and rock mass.If the pullout force is small,the bolt,grouting mass and rock mass will cooperatively bear external loads.However,when the load increases to a certain extent,the interface between anchor body and rock will enter the state of shear yielding and be destroyed after reaching peak strength.Meanwhile,the larger the linear stiffness of bolt body,the higher the corresponding pullout force is needed.Therefore,it is very important to select reasonable linear stiffness and groove space of bolt for simulating anchoring effect in weak and fractured rock mass.

关 键 词：软弱破碎岩体 锚杆 抗拔力试验 模型试验 

分 类 号：TU452[建筑科学—岩土工程]