(1. School of Energy Science and Engineering,Henan Polytechnic University,Jiaozuo,Henan 454000,China;2. School of Architecture and Civil Engineering,Anyang Institute of Technology,Anyang,Henan 455000,China;3. Collaborative Innovation Center of Coal Work Safety and Clean High Efficiency Utilization,Henan Polytechnic University,
Jiaozuo,Henan 454000,China)
Abstract:End-anchored prestressed anchor cables,as an effective and economical reinforcement method,are widely used in rock support applications. Shear failure for the free section of end-anchored anchor cables is a common failure type of anchor cables in engineering practice. Its failure mechanism differs from that of full length anchoring cables,which requires further in-depth research. By using the research methods of laboratory test,theoretical analysis and numerical simulation,the characteristics of shear failure in the free section of anchor cables were clarified,and the mechanical mechanism and micro-evolution laws of shear failure in prestressed anchor cables were revealed. The study showed that the shear action on joint surfaces caused coupled growth of axial and shear forces inside the anchor cable,and the steel strands at the fracture exhibited both tensile and shear failure modes. The axial force and shear force in the anchor cable at the inflection point were positively correlated. Based on the combined tensile-shear failure criterion,the mechanism of shear failure in anchor cables was well explained. During the shear process,there were both tensile stress concentration area and tensile-shear composite stress concentration area. Shear damage on the surface of the outer steel strands of the anchor cable resulted in earlier failure,and the evolution law of internal forces in the anchor cable confirms that shear failure in the anchor cable was a combination of tension and shear failure. The research results provide a reference for the development of anchor cable support technology.
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