. When Real-time mined 80 m, the very first caving occurs in ahead of the
. When Real-time mined 80 m, the first caving happens in before the excavation. the (Z)-Semaxanib site surface the coal seam ismonitoring on the surface is conducted the working face, along with the caving subsidence through the mining course of action with the functioning facestrata, along with the collapsed into a height is 17.3 m. The improvement is terminated in the S3 is recorded and Alvelestat Metabolic Enzyme/Protease plotted rock curve, that is shown in coal seam floor. At this time, the mining fractures mined-out blocks are stacked on the the diagram in Figure five. Together with the enlargement of theare mostly location, the surface S2 strata and are separated from the S3 boost. Within the process of coal distributed in thesubsidence and influence variety graduallystrata. When the coal seam is seam 96 m, the sliding motion with the S2 rock strata a “U” shape. Due leads to sliding minedmining, the surface subsidence curve presentsdue to shear failureto a specific slope around the surface, the a “cutting symmetrical the coal seam is mined 160 m, 200 m and instability, forming curve is notbody”. Whento the center of the goaf. In the early stage of operating face mining, seems within the overlying comparatively flat. caving step the sliding 248 m, periodic cavingthe subsidence curve was strata, periodicThen, due todistance is and m, the surface is overlying rock periodic step cutting body” structure, there are actually 408instability in the accompanied by”inclined cracks, mainly current within the major on the measures breaking on surface. At this time, the subsidence value on the monitoring point functioning face along with the boundary. Due to the shallow depth of the coal seam, the surface corresponding towards the surface the raise face, forming a penetrating subsidence reachcracks ultimately connect withwill working sharply with the maximummining crack. The ing 7250 mm. Based on the surface rock inside the formation the measured maximum surface is characterized by step failure, resulting movement information, of rock pillars. According subsidence value is 7000 mm. It that, at the that the numerical overburden failure is always to the simulation benefits, it can be foundcan be seencoal mining stage, thesimulation outcomes are ladder-shaped, andresults, indicating that the microscopic mechanical parameters from the close for the actual the roof will form a “inclined step cutting body” structure, that is prone to sliding instability, this paper in Figure four. Based on the evaluation, the overlying numerical model taken in as shown are reliable and correct. strata produced the whole inclined shear fracture inside the mining course of action of a 22,021 functioning face. Below the influence of its personal gravity and coal mining components, the blocks formed after the fracture are prone to slide and cause instability from the overall structure. The blocks formed soon after the shear fracture with the overlying strata are referred to as the “cutting body”. The structure formed by the interaction in the “cutting body” is the “inclined step cutting body” structure. Due to the poor bearing capacity in the structure, with the sliding instability, the overburden movement produces more load on the support. At this time, the overlying load is completely transmitted, resulting in severe stress around the working face, and it really is prone toAppl. Sci. 2021, 11,9 ofroof fall accidents. The structure reasonably explains the phenomenon of security accidents in shallow coal seam mining. Real-time monitoring on the surface is performed before the excavation. The surface subsidence for the duration of the mining course of action in the functioning face is recorded and plotted into a curve, wh.
