Analysis and Design of Protection Device for Anchor Cable Pull-Out in High-Stress Roadways

Abstract

In regions with high-stress roadway stress, anchor cables frequently experience damage, leading to risky pull-outs and ejections. This study aimed to determine the dynamics of such incidents, refine protective devices, and validate their efficacy in enhancing safety. Drawing from an ejection accident in the 1632 (3) roadway of Pan San Mine, a combination of laboratory experiments, theoretical analysis, simulations, and field applications was utilized. The kinetic energy and speed of cable ejections were determined from single-axis tension test data. Based on these insights, a spring-based protection device was conceptualized. Subsequent experiments and simulations evaluated the energy absorption and deformation characteristics of these devices with different diameters. The results included the following: A cable, during ejection, moved at 48 m/s. Spring protective devices of 4 mm can absorb more energy than the 5 mm, but the anti-ejection effect is poor respectively. Increasing the device diameter improved its performance, especially in controlling spring deformation rate and preventing cable lock-ups. This devised protection mechanism showed promising results when implemented in the 1511 (1) roadway of Zhangji Mine.

Calculation and Analysis of Load Transfer Characteristics of Tensile Anchors for Geotechnical Anchoring Systems

“…Geotechnical anchoring technology involves embedding anchors into the geotechnical body to transfer stress through the integration of the 'anchor-grouting-geotechnical body' system (refer to Figure 1). This process not only fortifies the strength of the geotechnical body itself, but also enhances its stability [1]. Since the 1950s, geotechnical anchoring technology, owing to its simplicity and cost-effectiveness, has found widespread application in various geotechnical engineering challenges such as foundation pits, tunnels, and slopes, yielding positive outcomes [2].…”