Analysis of shear characteristics of prestressed anchor cable and shear resistance of anchor joint plane

Abstract

Reinforcing a high and steep rock slope is important in a water conservancy project. Accordingly, a prestressed anchor cable is the most commonly used slope reinforcement technology. In relevant standards, the prestressed anchor cable is considered as a tensile structure. In practical engineering, prestressed anchor cable is subjected not only to tensile load, but also to shear load. In this study, a large indoor direct shear test was designed to examine the shear characteristics of a jointed rock mass and the shear rupture rule of the prestressed anchor cable. The shear tests of different anchorage modes (i.e., full-length bond and full-length non-bond), different vertical normal stresses, and different prestress were designed. The results show a significant difference in the shear displacement curves between the full-length bonded anchor cable and the full-length unbonded anchor cable during shearing. The vertical normal stress and the prestress can effectively improve the shear strength of the joint in the front period; however, the higher the prestress, the smaller the shear displacement when the anchor cable is destroyed. The damage of the two types of prestressed anchor cables is basically the same and occurs first at the plastic hinge position.