Study on surrounding rock control performance of pile-anchored energy-absorbing hydraulic support in rockburst roadways of kilometer-deep mines

Abstract

Economical and effective prevention of rockbursts in kilometer-deep mines remains a critical challenge for the mining industry. We statistically analyzed rockburst occurrences and characteristics in China, reviewing structural configurations and working mechanisms of existing energy-absorbing hydraulic supports. To address application bottlenecks of current supports in deep roadways, we designed a novel pile-anchored energy-absorbing hydraulic support (PEAHS) for roadway reinforcement based on surrounding rock control and structural stability principles. The system utilizes foundation piles as coupling elements to achieve rock-pile-support interaction that collectively resists dynamic impacts. We further conducted preliminary assessment of pile specification effects on support performance, the support effect achieved by increasing the pile diameter and length was verified.Through numerical simulations of the 615 working face gateway at Longjiapbao Coal Mine (Jilin, China), we demonstrate that the PEAHS effectively controls:(1) Controlling floor heave through restriction of surrounding rock sliding; (2) Reducing surrounding rock plastic deformation via optimized plastic zone distribution; (3) Modulating surrounding rock energy dissipation patterns.Comparative analysis of four support scenarios-gantry-type hydraulic support, PEAHS, pile only, and unsupported roadway-confirms that PEAHS provides equivalent roof and rib stabilization to conventional gantry-type support while delivering superior floor restraint performance.