Similar simulation test study on overburden migration in areas affected by fault clamping under mining conditions

In order to explore the influence of fault clamping affected area on overburden migration under mining conditions, based on the mining geological conditions of fully mechanized mining face 6305 in Xinjulong Coal Mine, the overburden structure,displacement characteristics and fault activation characteristics before,during and after mining from the face to the fault clamping affected area were analyzed by using indoor simulation method. The results show that the arch structure is formed after overlying rock failure in the 6305 fully mechanized mining face before F311 and XF2 faults. When mining to faults F311 and XF2,the “arch” overlying rock structure is strangely different and the “ arch” overlying rock structure is discontinuous. After mining fault F311,the arch foot of the “arch” overlying rock structure falls on the low rock layer of the footwall,and the stress at the arch foot increases,resulting in the overall cutting of the low rock layer. After mining fault F311,a new strange “ arch” overlying rock structure is formed between the working face and XF2 fault. When the working face 6305 started mining,the F311 fault first showed activation characteristics. When the working face was pushed to the F311 fault, the maximum subsidence displacement of the lower strata was 9. 0 m,while the upper strata had no subsidence displacement. In this case,the F311 fault was activated significantly at the lower strata while the upper strata did not activate. When the working face is pushed to the XF2 fault,the maximum subsidence displacement of the lower strata is 7. 8 m,while the upper strata has no subsidence displacement. In this case,the XF2 fault is obviously activated at the lower strata,while the upper strata is not activated.