预应力锚索锚固段粘结破坏本构模型研究  

Study on the Constitutive Model for Bond Failure of Pre-Stressed Cable Bolt

作　　者：朱训国[1] 关洪峰[2] 

机构地区：[1]大连大学材料破坏力学数值试验研究中心,辽宁大连116622 [2]铁煤集团公司大兴矿,辽宁调兵山112700

出　　处：《大连大学学报》2007年第6期20-26,共7页Journal of Dalian University

基　　金：国家自然科学基金资助项目(50679015)

摘　　要：为了验证本文建立的锚索/注浆体耦合本构方程的正确性,对不同试验条件下的拉拔试验进行了数值模拟.分别对径向压力为常数,径向刚度为常数下的拉拔试验进行了数值模拟,并对其进行各相关参数、不同围岩应力变化等参数条件下的力学效果进行了详细的分析,得出了影响锚索锚固效果的相应的影响因素:注浆体的力学特性、锚索单元的围压及其刚度和由于岩体开挖引起的原岩应力场的改变.并且通过数值模拟可以看出,不同围压锚索体内的轴向载荷与其轴向位移、轴向位移与其径向位移之间的函数关系.轴向载荷随着轴向位移的增大而成增大的趋势,同时,水灰比低的锚固单元锚索的承载力比水灰比高的锚固单元要高;而且,在锚索轴向载荷的作用下,锚索的径向位移与其轴向位移基本呈线性关系.在岩体开挖后,岩体内的应力状态的改变对锚固体的应力分布有较大的影响作用,其应力状态的改变可以较大的影响锚索的轴向载荷的等作用载荷的分布.All results of pull experiments have been numerically simulated under different experimental conditions for validating the cable/grout coupling constitutive model to determine whether they are right or not. According to the different experimental conditions ,to determine the cable bolt failure under constant radial stiffness and constant radial confining pressure. And the cable bolt mechanical properties are analyzed under different correlative parameters and different confining pressure. Through the analysis, the factors influencing the cable bolt anchorage effect is known. There are the grout properties ,the confining pressure of outer surface for grout and the stress field variation for rock mass excavation. And the relations of the cable bolt axial force and axial displacement,and the axial displacement and radial displacement through the numerical curve profile under different w ： c and the confining pressures are analyzed. It is concluded the ultimate capacity of low w ： c anchorage element is higher than that of the high w ： c anchorage element. A work hardening property is presented. It is revealed that there is a linear relation between axial displacement and radial displacement of cable bolt. An anchorage effect is affected by the stress field change for rock excavation for different reason. So through the above-mentioned analyzing results, the affecting reasons of anchorage effect are：the grout quality, the radial confining pressure or radial stiffness of the borehole rock, and the stress field change for rock mass excavation.

关 键 词：锚索 数值模拟 影响因素 锚固效果 

分 类 号：TD355[矿业工程—矿井建设]