Protection Scope and Effect on Close Lower Protective Layer Mining

Fei Guo

《World Scientific Research Journal》 7卷11期 (2021/11) Pp. 182-187

https://doi.org/10.6911/WSRJ.202111_7(11).0026

摘要

Based on the engineering background of mining coal seam No. 2 in Taoer coal mine as the close lower protective layer of coal seam No. 1 in Handan of Hebei Province, the effective protection scope and effect were determined through theoretical calculation and parameter test. The results show that the pressure relief angles of tendency δ1, and δ3 is 73° and 83°, respectively, and the strike relief angle δ5 is 56°. Coal seam No. 1 as the protected layers is within the maximum protection vertical distance, and the minimum layer spacing without damaging the mining conditions of coal seam No. 1 is 34.29 m. After the mining of the coal seam No. 2, the maximum residual gas content and residual gas pressure of coal seam No. 1 are 3.11 m3/t and 0.18 MPa respectively, which are reduced to 33% and 20% before mining. The minimum value of the maximum expansion deformation of coal seam No. 1 is 10.2 ‰. In summary, it achieved a good effect of pressure relief and outburst elimination.

關鍵字

Coal and gas outburst ； Protective layer ； Relief angle ； Protection Scope ； Protective effect

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