Mechanism and stability evaluation of goaf ground subsidence in the third mining area in Gong Changling District, China

This paper investigates the formation mechanism, relevant influential factors, and distribution laws of the collapse in the third mining area in Gong Changling District, Liaoyang City, China, by employing geological surveying, geophysical investigation, and theoretical analysis. The preliminary evaluation and prediction of ground settlement induced by the goaf collapse are presented. The results show that mining is the primary factor contributing to the ground subsidence and that groundwater infiltration accelerates this process. The three-zone model is proposed to analyse and evaluate the stability of the goaf. Based on this model, we conclude that the strata in the mined area and the surrounding non-mined area are unstable and could be subjected to ground subsidence and ground fissure once disturbed.