Load transfer laws of tensile anchors in rock masses with weak interlayers based on a shear-slipping updating model  

作　　者：WANG Yan XIANG Xin LI Chang-dong ZHU Guo-qiang SONG Cheng-bin XIAN Jin-ye ZHANG Jia-jun 

机构地区：[1]Faculty of Engineering,China University of Geosciences,Wuhan 430074,China [2]China Three Gorges Corporation Limited,Beijing 100038,China [3]Three Gorges Research Center for Geo-hazards Ministry of Education,China University of Geosciences,Wuhan 430074,China

出　　处：《Journal of Mountain Science》2022年第3期812-825,共14页山地科学学报（英文）

基　　金：supported by the National Key R&D Program of China(Nos.2018YFC1505300,2017YFC1501304);National Natural Science Foundation of China(Grout Nos.42090054,41922055 and 41931295);the Fundamental Research Funds for the Central Universities,China University of Geosciences(Wuhan)(No.CUGGC09);Research Project of China Three Gorges Corporation(No.2019073);the Zhejiang Huadong Construction Engineering Co.,Ltd.(No.KY2019-HDJS-07)。

摘　　要：The load transfer characteristics of a tensile anchor in the rock mass with weak interlayers were investigated,considering the nonuniform stress of the horizontally layered rock mass along anchors.An improved shear-slipping model was proposed to describe the stress evolution characteristics of the bolt-rock interface.Based on the improved model,analytical solutions of the axial force,shear stress distribution and load-displacement relationship considering the residual stress stage were established.The effects of the stratigraphic sequence,pulling force and bolt diameter on the stress distribution of the anchorage interface were evaluated by using analytical solutions.The results were verified by applying the finite difference numerical simulation method.The sensitivity of each parameter to the axial force and shear stress of the rock bolt was determined based on calculation of the sensitivity coefficient.The study results show that the axial force and shear stress tend to decrease nonuniformly along the rock bolt towards the anchorage depth.Due to the existence of weak interlayers,the shear stress mutates at the weak and hard rock interface,and the axial force appears to“rebound”at the bottom of the anchored section.Lithology has more significant effects on the axial force and shear stress at the bottom of the anchor than at the top of the anchor.The pulling force is more sensitive to the anchor stress than stratigraphic sequence when the bolt diameter is determined.This study provides a theoretical framework for the fundamental problem of tensile bolts in horizontally or vertically laminated rock masses,providing a theoretical basis for anchor design.

关 键 词：Weak interlayer Tensile anchor Residual stress Shear-slipping updating model Sensitivity 

分 类 号：TU45[建筑科学—岩土工程]