Analysis of the Stability of Rock Masses in Deep Vertical Shafts under Blasting Disturbance Loads

During the construction of deep vertical shafts using the drill−and−blast method, the blasting−induced load acting on the shaft wall has caused significant degradation in the service performance of the surrounding rock. To investigate this issue, the influence process of blasting impact loads on the stability of the surrounding rock in shaft engineering was analyzed through numerical simulation. A coupled damage model was established based on the maximum nominal strain criterion and the Mohr–Coulomb failure criterion, with the aim of investigate the effects of blasting on the surrounding rock mass. In the research process, numerical simulation techniques were employed to reproduce the dynamic response of the surrounding rock under blasting loads. The loading conditions associated with blasting were systematically applied, and the mechanical response and damage evolution of the surrounding rock were examined. The composite damage model integrating the maximum nominal strain criterion and the Mohr–Coulomb failure criterion was used to describe the progressive degradation behavior of the rock mass. Based on this model, the spatial distribution and temporal evolution of damage within the surrounding rock were quantitatively evaluated. The results show that the damage evolution of the shaft surrounding rock under blasting loads exhibits pronounced spatiotemporal dynamic characteristics, accompanied by a distinct mechanical coupling mechanism. In the temporal dimension, damage development presents a staged concentration phenomenon. During the later stage of blasting−induced dynamic response, plastic dissipation energy dominates the energy evolution process of the surrounding rock. At this stage, the rock mass undergoes significant damage and failure, and there exists a potential risk of rock burst. The findings of this study can provide a basis for the safe construction of deep vertical shafts.