Research on time-varying evolution law of overburden stress field and fracture field in shallow coal seam mining

The mining stress formed in the surrounding rock after coal seam mining is the root cause of the damage and fracture of the stope surrounding rock. In order to study the evolution characteristics of mining stress and the fracture process of overlying strata on the mining face, a numerical model was established to simulate the evolution law of stress field and fracture field in the mining process of the working face by taking the 40101 mining face of Gaoliang Coal Mine as an example. The results show that the relationship between rock collapse and failure can be judged by using Mohr-Coulomb criterion to analyze the variation law of the difference between maximum and minimum principal stresses. The correctness of the time-varying evolution of fracture field and stress field in working face mining can be verified by comparing the numerical simulation results with the field measured results.