榆神矿区顶板水井下钻孔疏干降压技术研究

Underground drilling and draining depressurization of roof water in Yushen mining area

锦界煤矿属水文地质条件极复杂型矿井,煤层顶板砂岩裂隙水和第四系松散岩类潜水是矿井主要涌水来源,煤层埋深浅,上覆含水层与煤层距离近,采煤活动形成的导水裂隙带高度超过隔水层厚度直接与含水层贯通形成的涌水通道给含水层水进入采煤工作面创造了良好条件。以锦界煤矿3盘区位于井田边界工作面为研究对象,采用FLAC^(3D)数值模拟软件模拟计算了天窗区和正常隔水层区(正常区)两种不同地质条件的疏干降压过程中的孔裂隙水渗流规律和孔隙水压力场变化规律。研究结果表明:疏干降压工艺改变了天窗区和正常隔水层区(正常区)地下水渗流场,起到了疏干降压的作用。与正常区不同,天窗区疏干降压孔流速快、疏干降压效果明显。

Jinjie Coal Mine is a mine with extremely complex hydrogeological conditions,the roof sandstone fissure water and quaternary loose rock diving are the main source of water gushing in the mine.The coal seam is shallow,the overlying aquifer is close to the coal seam,and the height of the fissure zone formed by coal mining activities is higher than the thickness of the aquifer.The water gushing channel in the fissure zone formed by coal mining activities is directly connected with the aquifer,which creates good conditions for the aquifer water to enter the coal face.Taking the coal face at mine field boundary of Jinjie Coal Mine as the research object,fluid-solid coupling simulation software FLAC^(3D) was used to simulate and calculate the seepage law of pore fissure water and the change law of pore water pressure field in the process of draining and depressurizing in the skylight area and the normal water-barrier area(normal area)under two different geological conditions.The results show that the drainage and depressurization process changes the groundwater seepage field in the skylight area and the normal waterinsulating layer(normal area),and plays a role in the drainage and depressurization.Different from the normal area,the skylight area has a fast flow rate and obvious drainage effect.