缩管式让压吸能锚索抗剪特性试验研究OA

With the gradual commencement of construction of key projects in central and western regions of China,the control of large deformation in the surrounding rock of deep buried tunnels has become an engineering technical challenge that needs to be solved in China.The steel pipe shrinkable energy-absorbing cable,characterized by its stable resistance,high controllability and excellent energy absorption capacity,holds promise for addressing the issue of the large deformation in deep engineering construction.Given the commonly observed shear damage characteristics of the support structures in the jointed rock mass,a full-scale double shear test on the cable was conducted to investigate yielding deformation characteristics of the steel pipe shrinkable energy-absorbing cables under rock mass shear action.The test results reveal a constant resistance stage in the load-bearing curve of the energy-absorbing cable.This stage effectively prevents cable fracture through the yielding deformation of the constant resistor,which accommodates rock shear deformation while reducing shear stiffness during the shearing process.Concurrently,the axial load experienced by the energy-absorbing cable remains constant after reaching the designed constant yielding resistance value,enabling it to provide constant resistance to yielding deformation that aligns with the deformation of surrounding rock while maintaining a constant support resistance.Compared with traditional cables,the maximum shear displacements of the 160 kN and 350 kN energy-absorbing cables increase by 89%and 76%respectively,with the absorbed energy rising by 29%and 108%respectively.In the process of rock shear deformation,the energy-absorbing cable can effectively accommodate large surrounding rock deformation while significantly enhancing its energy absorption capacity,thereby providing robust technical support for the prevention and control of surrounding rock deformation disasters in underground engineering construction.