关键词: 拉压分散型锚索, 内锚固段受力机制, 设计方法, 工程应用

Abstract: A new tension-compression dispersive anchor cable was recently adopted in projects, which is based on the combination of tension, compression and load dispersive anchor cables. However, there is a limited study on the mechanism and design method of the anchor cable. Based on the Kelvin solution, we derived analytical solutions of the shear stress between surrounding rock (soil) and the anchoring segments of the tension-dispersive and compression-dispersive anchor cables, respectively. According to the superposition principle, a simplified calculation method was proposed to obtain the shear stress between anchoring segment and surrounding rock (soil). On the basis of theoretical results, the new anchor cable was applied in practical engineering, and the basic performance test of the anchor cable and the comparison with the prestress loss of the tension-dispersed anchor cable were performed, respectively. Theoretical results indicated that the values of shear stress at both ends of the unit anchoring segment were relatively higher, while the stress reached the lowest in the middle. The distribution characteristics of shear stress were consistent with testing results in the literature and numerical simulation results. According to testing results, i.e., the bearing capacity of the anchor cable, the peak values of shear stress in tension and compression sections were obtained using the simplified method, which agreed well with peak values of shear stress by means of the uniaxial compressive strength of rock in tension and compression anchor cables. The comparison results and the long-term monitoring data reveal that the effect of engineering application is good, and the load transfer of the anchor cable is stable and reliable.

Key words: tension-compression dispersive anchor cable, mechanism of anchoring segment, design method, application