Study on the response characteristics of roadway borehole pressure relief surrounding rock under strike-slip high-stress distribution

Abstract

To effectively address instability and control failure caused by high roadway stress, this study focuses on the engineering context of the Jinfeng Gold Deposit in southwestern Guizhou. It simulates and analyzes the response of surrounding rock in high-stress roadways affected by strike-slip stress distribution (σH＞σv＞σh) under varying drilling and pressure relief parameters, and conducts on-site experiments and monitoring. The study reveals that under strike-slip stress conditions when stress relief in the roadway’s surrounding rock equals the initial vertical stress, the stress distribution maintains a ‘bimodal’ pattern. Establish an evaluation method for the stress range in the three-zone during pressure relief and the optimization of drill hole diameter-spacing design. The optimized drilling relief plan effectively shifts stress concentration, and the peak stress near the roadway decreases to the original rock stress level, with a 3.5 MPa reduction at the far end and a horizontal shift of 4.79 m with the unloading level (εL) reaches 0.8375. Practical implementation confirms the effectiveness of the pressure relief design in unloading and transferring stress from the high-stress roadway’s stress concentration area, achieving a 43.14 % deformation optimization on both sides of the roadway. These findings provide valuable references for controlling stress relief in high-stress roadways surrounding rock.