State Key Laboratory for Geomechanics and Deep Underground Engineering School of Civil and Architecture
Engineering, China University of Mining and Technology

为解决预留煤柱造成的资源浪费问题,基于城郊煤矿大埋深破碎顶板特殊条件,对切顶卸压成巷开采技术可行性进行研究。根据城郊煤矿21304综采工作面的地质情况,工作面留巷段采用定向预裂爆破技术辅之以恒阻大变形锚索对留巷段进行加强支护,留巷段沿工作面方向距回采侧煤壁200 mm处预留深8 m、间距600 mm、与垂直方向成15°预裂孔进行定向爆破切缝;在顶板施工两排长10 m,距切缝孔300 mm,间排距400 mm×700 mm,预紧力不小于280 k N的恒阻锚索进行永久支护。留巷试验段减小了大埋深破碎顶板对留巷技术的影响,实现了大埋深条件下沿空留巷无煤柱开采,并为切顶卸压沿空留巷技术在类似条件的矿井应用提供经验。

In order to solve the waste of resources caused by the reserved coal pillars, based on the special conditions of deep burial and broken roof in Chengjiao Coal Mine, the feasibility of gob-side entry retaining by roof cutting and pressure releasing was studied based on the special conditions of broken roofs in Chengjiao Co al Mine. According to the geological condition of 21304 mining face, the directional pre-splitting blasting technology of the working face was supplemented by the const ant deformation and large deformation anchor, and the retaining road was supported along the working face coal wall 200 mm at the depth of 8 m, spacing 600 mm, and the vertical direction into a 15° pre-split hole for directional blasting; in the roof construction of two rows of 10 m long and away from the slit hole 300 mm, spacing400 mm, row spacing 700 mm and preload was not less than 280 k N constant resistance anchor for permanent support. The test section of the retaining roadway showed t hat gob-side entry retaining by roof cutting effectively reduced the influence of the large burial broken roof on the roof retaining stability, and the technology of gob-side entry retaining in large buried depth was achieved, which provided invaluable experience for the similar roadway.