关键词: 沿空留巷, 埋深, 相似模拟, 覆岩裂隙

Abstract: The stress of the concrete wall and coal pillar along the roadway is closely related to the structure formed by the collapse of the rock layer above. In order to obtain the caving structure and fracture evolution law of overlying rock on the goal-retaining working face of Daliuta coal mine, the study on the overlying rock structure and fracture evolution law of 52606 working face of Daliuta coal mine was carried out by using the method of similar material simulation experiment and theoretical analysis, and the influence of the change of buried depth from the cutting hole side to the stopping line side on the ore pressure development of 52606 working face was revealed. The influence mechanism of buried depth on mine pressure and surrounding rock along goaf is put forward. The results show that after the mining of the 52606 face, the burial depth gradually increases from the cutting hole to the stop-mining face, and the corresponding period of pressing step increases. The period of pressing step is 10m when the depth near the cutting hole is shallow, and the period of pressing step increases to about 20m with the increase of burying depth. At the same time, the corresponding caving Angle is obviously different. The caving Angle on the side of the stop-mining line with larger buried depth is 34°, and the caving Angle on the side of the cut hole with smaller buried depth is 43°. In the process of advancing the working face from a small buried depth to a large buried depth area, the range of abutment pressure stress increase, the stress concentration coefficient increases, the distance from the peak stress position to the working face decreases, and the crack density of the working face roof increases, which is not conducive to the formation of support structures in the large buried depth area and is not conducive to the stability of lane retention. The above analysis is consistent with the field observation.