岩土力学2012，Vol.33Issue(4)：1067-1074,8.
节理岩体锚杆的综合变形分析
Synthetical deformation analysis of anchor bolt in jointed rock mass
摘要
Abstract
Based on the former experimental and theoretical researches on the reinforcement mechanisms of anchor bolt in jointed rock mass at home and abroad, and comprehensive considering of the tangential and axial deformability of anchor bolt, a deformation model of joint bolts under shear load is proposed. The deformation of joint bolts is divided into two parts: elastic deformation zone and crushing failure zone. A variable is introduced to express the length of crushing failure zone. Mechanism of interaction between bolts and rock mass is analyzed. Relationships between tangential load and tangential displacement, and axial load and axial displacement are deduced respectively. Through the analysis of yield failure model of bolt, a method to calculate the length of the crushing failure zone is proposed. Finally, a calculation example is presented to study the relationship between the length of crushing failure zone and the parameters, such as the bolt diameter, the rock mass strength, anchorage angle and so on. It is concluded that: (1) The shear resisting function of joint bolts is actually that the bolts arouse the compressive strength of rock mass to resist the shear load of the joint plane. In the hard rock with higher compressive strength, the crushing failure zone is limited near the joint plane and the influence area of bolt is small; while in soft rock with lower compressive strength, the length of crushing failure zone and shear deformation and the influence area of bolt is larger. (2) The yield failure mode of anchor bolt is related to rock properties and diameter of the bolt. Shear yield occurs in hard rock and bending yield occurs in soft rock. Bolt with little diameter usually go through shear yield and bolt with large diameter may go through bending yield. After yield failure, the plastic hinge appears. The length of the crushing failure zone on one side of the joint is 1-2 times of the bolt diameter, however, it no longer increases with the increasing of shear load. (3) The optimal anchor supporting angle of joint anchor bolt varies with rock properties. Hard rock has a smaller anchor supporting angle and the soft rock has a larger one.关键词
节理岩体/锚杆/剪切荷载/挤压破坏段Key words
jointed rock mass/ anchor bolt/ shear load/ crushing failure zone分类
建筑与水利引用本文复制引用
张伟,刘泉声..节理岩体锚杆的综合变形分析[J].岩土力学,2012,33(4):1067-1074,8.基金项目
中国科学院知识创新工程重要方向项目“煤矿深井巷道围岩稳定性分析与控制理论研究”(No.kzcx2-yw-152) （No.kzcx2-yw-152）
国家自然科学基金重点项目“西部高地应力结构性流变岩体的破坏机制及锚固可靠性研究”(No.90510019). （No.90510019）
