Research On Migration Characteristics Of Overlying Strata And Optimization Of Staggered Distance In Ultra-close Coal Seams

In China,the occurrence of very close coal seam is more extensive,but the research results on the mining of very close coal seam are less,and many scholars only make empirical summary on the mining technology of very close coal seam.This article combines Shanxi Lingshi Jiguang Coal Mine No.9 and No.10 in ultra-close coal seams as the engineering background.At the same time,the research results of many scholars and experts in the previous period are used as the reference basis,through theoretical analysis,FLAC3D software simulation,physical similarity simulation and field measurement Research methods such as Jiguang Coal Mine's very close coal seam overlying migration characteristics and optimization of the same mining fault distance were studied,and the following conclusions were obtained:(1)Based on the theory of stabilization zone,and also considering the impact of support pressure on mining face,the reasonable distance between coal seams at very close distances under the condition of simultaneous mining is obtained;based on the theory of pressure reduction zone,simultaneous mining work is established Based on the surface calculation model,a reasonable offset value was calculated;by comparing the feasibility of the two schemes,it was finally determined that Shanxi Lingshi Jiguang Coal Mine is more suitable for the layout of the stabilization zone.(2)The FLAC3D numerical simulation software was used to compare the stress disturbance and roof subsidence of No.9 coal and No.10 coal in the Lingshi Jiguang coal mine of Shanxi under different offset values.Finally,the stress disturbance and roof subsidence of the same mining offset value of 36m were determined.The smallest amount is the best mining offset.(3)With the aid of physical simulation tests,the overlying strata migration of the upper and lower coal seams under different staggered distances was summarized and analyzed,and the stress and displacement changes of the stope under different staggered distances were compared and analyzed,and the reasonable staggered value of the same mining face was finally determined.(4)Combined with the actual production conditions of the Jiguang Coal Mine in Shanxi,the 9th and 10th coal seams were measured on site.By analyzing the changes in the pressure of the upper and lower coal seams,the control range of the optimal and reasonable offset is 36m.Figure[37]Table[11]Reference[89]...