Numerical investigation of the dynamic response of a preconditioned roof in an underground mine: A case study of mining environment regeneration

To address issues of security, efficiency and cost in mining operations, the concept of mining environment regeneration (MER) is proposed. Mining environment regeneration is defined as improving the orebody occurrence conditions via geotechnical engineering techniques and providing safe mining conditions for workers and equipment. Therefore, artificial reconstruction bodies such as preconditioned roofs and pillars play a significant role in stope stability. Given the initial stress states and blasting dynamic disturbances, an artificial reconstruction body numerical model is established using the explicit dynamic software ANSYS/LS-DYNA. An implicit and explicit conversion technique is used to investigate the dynamic response process of a preconditioned roof (PR) under a combined static and dynamic loading condition. The peak particle velocity (PPV), peak pressure and strain energy density (SED) of key points are selected as the technical analysis indicators, and the dynamic responses in the PR are obtained. An industrial experiment is performed in an underground mine based on the numerical results. By combining on-site blasting vibration-monitored data and numerical simulation results, we provide reasonable guidance in practical mining production.