近距离采空区下煤层开采矿压显现特征研究

Study on pressure characteristics of coal seam under close mined-out area

以湘桥煤矿10#煤层开采为工程背景,对上覆采空区的底板破坏情况以及下伏煤层开采的顶板变形进行了理论分析,采用UDEC数值模拟软件对比分析了单一煤层开采与近距离采空区下煤层开采的矿压显现规律。结果表明:相较于单一煤层开采,近距离采空区下煤层开采支承压力应力集中程度更高,其超前支承压力强度更大;同时,由于近距离采空区下煤层开采属于重复采动,下煤层顶板岩层破坏较单一煤层开采更为严重,采场支护强度设计必须考虑上部采空区的影响。因此,在进行近距离采空区下煤层开采时必须采取加强下伏煤层开采超前支护、提高采场液压支架支护强度等措施,以保证近距离采空区下煤层开采顶板的有效管理和安全回采。

The 10# coal seam of Xiangqiao Coal Mine are taken as the engineering background, the failure of the floor of the overlying goaf and the deformation of the roof strata of the underlying coal seam were analyzed theoretically, and the coal pressure behavior law between the single coal seam mining and the coal seam mining under the close mined-out area was compared and analyzed by using UDEC numerical simulation software. The analysis results show that: compared with the single coal seam mining, the support pressure stress concentration of coal mining under the close-distance goaf is higher, the strength of advanced abutment pressure is greater, and the roof strata damage of the lower coal seams is more serious than that of single coal seam mining due to coal mining under close-distance goaf belongs to repeated mining. The support strength design of working face must consider the influence of the upper goaf. Thus, when mining under close-distance goaf, the measures that strengthen the advanced support of the underlying coal seam and improve the support strength of the hydraulic support in working face must be taken to ensure the effective management of the roof and safe mining.