关键词: 节理面, 锚索, 剪切试验, 预应力, 销钉作用, 轴力增量

Abstract: By a series of shearing model test, the effect of anchor cable on shear resistance behavior of smooth joints are studied under different normal stresses, prestresses and anchorage conditions. In the model test, shear resistance of dowel force, prestressing force and increment of axial force is separated and the shear contribution of three forces is discussed deeply to joint planes. Contribution to shear strength of joints is discussed due to dowel effect, prestress and increment of axial force in the shear progress, and failure mode of cable simulant is analyzed. Experiment results show that prestressed anchorage improve shear resistance and shear stiffness in initial phase of shear, and prompt joints to show characteristic of plastic-hardening. Experiment results also reveal that effect of prestress on joint shear strength is related with test condition, condition of joint planes and anchorage angle. Experimental and theoretical analyses show that prestress force and dowel effect play a major role in the initial phase of shear displacement and the increment of axial force play an important role after formation of plastic hinge. Cable failure usually occurred in the vicinity of the shear joint due to the combination of shear load and axial load.

Key words: joint planes, anchor cable, shear test, prestress, dowel effect, increment of axial force