Characteristics of Collapse Accumulation Body in Roadway and Numerical Simulation of Rescue Channel Excavation

Abstract

After the coal mine disaster, the collapsed accumulation body blocked the roadway and interrupted the rescue route, which seriously affected the development of rescue. Based on the post-disaster blockage rescue route of the collapsed accumulation body, the morphology and structural characteristics of the accumulation body were analyzed, and the process of excavating the rescue channel in the collapsed accumulation body in the mining roadway was simulated using CDEM software, and the moving mode of accumulation body fragments was discussed. The study found that: the formation of the accumulation body is the process of continuous “self-organization” adjustment of the rock fragments; the accumulation body along the direction of the roadway axis is divided into three areas: pre-sorting accumulation area, post-sorting accumulation area, and non-sorting accumulation area; the particle size of the accumulation body-particle content conforms to the normal distribution; the harder the rock fragments constituting the accumulation body is, the particle size of the fragments is more different; the number of contact points of the fragments of the tightly accumulation body is more than that of the loose accumulation body; the excavation of the rescue channel is accompanied by the random “self-organization” movement of the accumulated body; the settlement and deformation of the accumulated body is actually the continuous collapse of the old arch structure, and the process of continuous formation of a new arch structure; the initial force of the rescue channel excavation is small, then it increases sharply, and finally stabilizes; the fragment adjustment forms are mainly divided into horizontal movement adjustment, vertical movement adjustment, rotation movement adjustment, and multi-directional movement adjustment. The research conclusion has certain guiding significance for the rescue channel excavation under the condition that the collapsed accumulation body blocks the roadway after the coal mine disaster.