# Numerical Simulation Analysis Method for Rockburst Control in Deeply Buried Caverns
## 2 Mechanism and Control Measures of Rockburst
### Control and Prevention Measures for Rockburst  
According to the mechanism of rockburst occurrence, there are two kinds of measures to prevent and control rockburst. One is to improve the external environment of rock mass and reduce energy accumulation. The other option is to enhance the internal resistance of rock mass and improve its bearing capacity. The engineering measures to prevent rockburst include the following aspects. (1) Prevention and control measures. Instruments and equipment can be used to judge whether there is a tendency of rockburst and to guide the evacuation to ensure the safety of the engineering. By evaluating the grade of rockburst we can change the construction method and plan and take reasonable measures to control the rockburst or reduce loss. The main methods of on-site rockburst prediction are as follows. 1 The geological analysis method. The rock mass characteristics can be analyzed through geological information and the high-stress degree can be evaluated to estimate the risk of rockburst formation. 2 Acoustic emission method. The acoustic wave detector can be used to detect the stress growth rate and crack degree inside the rock mass and the risk of rockburst can be predicted by the detection results. 3 Drilling cuttings method. By drilling and coring the rock, the degree of rockburst can be judged by the ratio of the cutting body volume to the borehole volume. 4 Electromagnetic radiation method. The risk of rockburst can be predicted by monitoring the changes in strength of electromagnetic radiation pulse signals in the rock mass. Although there may be some variations in the practical implementation of these methods, the comprehensive utilization of these measures can contribute to the prediction of rockburst. But, the above methods do not actively control the occurrence of rockburst. (2) Active control measures. From the point of view of energy, rockburst is caused by the sudden release of elastic strain energy stored in the rock mass, resulting in rock failure. Therefore, the idea of active control measures is mainly to control the excavation and blasting to reduce the energy accumulation of the rock mass and also to release part of the energy in advance to improve the external environment. Active control measures mainly include the following methods. 1 Smooth blasting. By controlling blasting, one can use short footage and multiple cycles to reduce surrounding rock disturbance, improve the stress state of the surrounding rock, and limit the occurrence of rockburst. 2 Reasonable excavation. One can optimize the design of the tunnel section, adopt appropriate excavation methods, and reduce the stress concentration of surrounding rock to reduce the risk of rockburst. 3 Stress release. By drilling on the working face and injecting water into it to release part of the energy, the softening of the surrounding rock can be promoted, reducing the grade of rockburst. These active measures are based on the energy point of view of rockburst to adopt some actions to improve the external environment of the surrounding rock and actively reduce rockburst. (3) Passive control measures. From the point of view of strength, rockburst is the cracking or ejection of the rock mass caused by the sudden release of the enormous elastic strain energy. Therefore, passive control measures mainly focus on strengthening the surrounding rock to improve its bearing capacity and combining support and surrounding rocks to enhance the overall stability of the surrounding rock. There are a number of typical passive control measures. 1 Spray anchor support. Spraying concrete can rapidly seal the surrounding rock and effectively control the occurrence of light rockburst. Anchor rods used to reinforce the surrounding rock can effectively enhance the overall stiffness and bearing capacity as well as prevent the ejection of cracked and peeled rocks. 2 Advanced support.