锚杆锚固界面荷载传递参数P-S曲线反演法适用性研究  

Research on the applicability of the anchoring interface load transfer parameters reached by the load-displacement curve inversion

作　　者：刘晓明[1] 蒋宏伟[1] 杨瑞峰[1] 

机构地区：[1]湖南大学土木工程学院,湖南长沙410082

出　　处：《水文地质工程地质》2015年第5期62-67,共6页Hydrogeology & Engineering Geology

基　　金：国家自然科学基金资助项目(50808076)

摘　　要：在锚杆受力机理研究中,常采用锚杆拉拔试验所得荷载位移曲线(P-S曲线)进行反演,以确定锚杆界面荷载传递模型的合理性、求得模型的参数。对于自由段不为零的锚杆拉拔试验,锚杆杆体的材料变异性对测试结果有一定影响,且影响随自由段长度增大而变得显著,现有研究从未考虑过。本文根据荷载传递法,推导了荷载位移关系理论模型,然后考虑杆体材料弹性模量的变异性,分析了评价自由段长度对于锚固体顶部位移计算结果影响的方法。最后,基于既有实例,分别研究了土层锚杆和岩层锚杆P-S曲线反演结果受自由段长度影响的程度。研究结果表明,P-S曲线反演方法适用于自由段长度小于5 m的土层锚杆,不适用于岩层锚杆。成果可供基于P-S曲线反演方法对锚杆荷载传递特性进行的理论研究参考。In the study of mechanism of bolt, the inversion of a load-displacement curve from the field test is often used to verify the rationality of the anchor interface load transfer model and obtain the parameters of the model. For the bolt pull test with a free segment, the variability of the anchor rod body has some influence on the result of the test and this influence increases with the increasing free segment length, while there is no concern about this up to now. According to the load transfer method, the derivation of the model of the load- displacement relationship is given and the analysis of the effect of the free segment length on the calculation of the displacement at top of the anchoring body is also put forward by taking the variability of the anchor rod body into account in this article. Based on the existing instance, the study of the effect of the free segment on the results of the load-displacement curve inversion is also given. The results show that the load-displacement curve inversion is suitable for the anchor free length less than 5 m in soil layer, and it is not applicable to the anchor in rock layer. These results can provide a reference for the theoretical research bolt load transfer characteristics based on the method of the load-displacement curve inversion.

关 键 词：荷载位移曲线(P-S) 荷载传递法 变异系数 误差 

分 类 号：TD353.6[矿业工程—矿井建设]