The shear resistance mechanism of prestressed anchor cables in slope reinforcement

At present, for the reinforcement effect of prestressed anchor cables, only the shear resistance produced by prestress is considered in slope reinforcement design, which greatly underestimates the shear resistance of anchor cables. To investigate the shear resistance effect of prestressed anchor cables, a large-scale shear test system of anchored joint with sample dimensions of 70 x 70 x 140 cm was developed in this study. The test results revealed the interaction mechanism of extrusion and disengaging between the anchor cable and local surrounding rock in the process of shear deformation, the reversed 'S'-shaped deformation characteristics of the anchor cable, and the combined tensile-shear failure mechanism. Based on the test results, the shear deformation and shear resistance characteristics of the anchored joint in different phases were thoroughly analysed, and a three-stage shear deformation model for anchor cables was proposed. In addition, the corresponding mechanical analysis model for shear resistance of anchor cables was developed. The comparative verification revealed that the error between the model calculated results and the test results was within 6%.