The Influence of Different Sublevel Heights on the Stability of Faults under Sublevel-Filled Synergistic Mining

At present, when addressing the problem of fault stability in mines, most attention is paid to the study of the impact of a single mining method on faults. In order to study fault stability in mines more comprehensively, this paper researches the effect of coordinated mining using multiple mining methods. For example, the sublevel caving method without the sill pillar and the lower-layer filling method of coordinated mining can be used to analyze the dynamic response law of the fault, as well as the stability of the fault in different mining conditions. In this paper, the stress field, displacement field and sliding trend index of the fault plane and orebody near the fault are obtained via numerical simulation and theoretical analysis methods, and the main factors affecting fault stability under different mining conditions are analyzed. The results show that under the influence of cooperative mining, the shear stress fluctuation of the fault surface and the ore body near the fault increase gradually with the sublevel height of the sublevel caving method without the sill pillar and the lower-layer filling method, and the indexes of slip tendency become larger, which may be a precursor of fault activation. In particular, the fault surface of the sublevel caving method without the sill pillar reflects the drastic change in the shear stress with the larger displacement, and the instability brought to the fault by the sublevel caving method without the sill pillar is greater than that brought to the fault by the lower layer filling method under the premise of only changing the height of the sublevel.