Control of rock burst during deep tunnel blasting excavation based on energy release process optimizing

Abstract

Blasting is widely used in hard rock tunnel excavation but often deteriorates the mechanical properties of the rock mass, forming a disturbance zone associated with energy evolution in the surrounding rock. In high-stress environments, this disturbance zone poses risks of engineering disasters like rock bursts. Previous studies confirm that optimizing the energy release process is an effective strategy for rock burst control. This research focuses on enhancing energy path optimization by analyzing parameters affecting the formation of the disturbance zone. Specifically, we conducted a sensitivity analysis of key blasting parameters, including caving hole spacing, caving blasting load, smooth blasting burden, hole spacing, and smooth blasting load. By exploring the impact of caving and smooth blasting under varied design conditions, we developed a method to control rock bursts through staged energy release, gradually disturbing the surrounding rock. Results indicate that aligning the disturbance zones induced by caving and smooth blasting can regulate the energy release process effectively, a staged and controlled energy release process is proposed to modulate the distribution and timing of strain energy dissipation, thereby reducing the risk of dynamic failure. This approach presents a novel method for managing rock burst tendencies in high-stress rock tunnel excavations.