Mechanism and control of strata pressure behavior anomaly in fully mechanized top-coal caving face of extra-thick coal seam

In order to solve the problem of strata pressure behavior anomaly and the difficulty of roof control in the fully mechanized top-coal caving mining face in Zhungeer coal field, the 6-upper coal seam in Suancigou coal mine was taken as the research object.Through theoretical analysis and field measurement, the mechanism of strata pressure behavior anomaly and roof control technology were studied.The results show that the roof structure model was set up with thin immediate roof which has a big roof hanging distance.Under the roof staggered type and parallel type fracture cases, the roof structure mechanics parameters were analyzed, and the relationship between roof pressure and roof parameters was obtained.Thinner immediate roof and higher roof toughness, more difficult to control the roof.The anomaly of strata pressure behavior occurs under the condition of parallel type fracture case.The control technologies in roof-control and goaf area and the new type of hydraulic support control technology were put forward and implemented.After the implementation of the technologies, the roof control effect was good, the safe mining was ensured, and the production effect was remarkable.This provides a reference for the roof control of similar conditions.