Study on Numerical Simulation of Overburden Fracture Development Characteristics and Prediction of Water-Conducting Fracture Zone Height in Shallow Coal Seam Mining

Abstract

The northern Shanxi mining region, a pivotal coal-rich area in China, is characterized by substantial reserves of shallow coal seams and distinctive geological mining conditions that exacerbate overburden rock fissure development. This study delves into the mechanisms governing overburden damage and fissure evolution in shallow coal seams using the theoretical frameworks of key strata and mining subsidence, augmented by numerical simulation methodologies. It also examines the impact on ground fissure morphology and propagation. Additionally, this paper investigates the prediction of water-conducting fracture zone heights in shallow coal seams. This paper’s findings reveal a sequential dynamic process in overburden rocks during mining: microfissure initiation, key stratum rupture, fissure aggregation, and fissure coalescence. Leveraging a long short-term memory (LSTM) model, this paper develops a prediction model for water-conducting fracture zone heights in shallow coal seams, achieving high accuracy with a mean squared error (MSE) of 2.29, a mean absolute error (MAE) of 1.22, and an average relative error of 2.51%. These results contribute scientific insights for mitigating ground fissure disasters and facilitating ecological restoration in the context of intensive shallow coal seam mining in northern Shanxi. Furthermore, they hold substantial scientific merit in advancing the theories of mining subsidence and stratum control in mining engineering.