不同煤厚条件下切顶卸压无煤柱自成巷技术应用

Application of Nonpillar Mining Technique with Automatically Formed Entry by Roof Cutting and Pressure Release Under Different Coal Seam Thicknesses

为了探究不同煤厚条件下切顶成巷技术体系,以禾草沟二号煤矿薄煤层工作面、店坪煤矿中厚煤层工作面和柠条塔煤矿厚煤层工作面为工程背景,研究了以煤厚为主要影响条件下的切顶成巷关键技术参数,并开展了现场工程试验。研究发现:巷道顶板切得开、留巷围岩护得好是保证切顶成巷技术成功实施的关键,其关键技术可概括为顶板定向预裂成缝技术、NPR恒阻锚索支护技术、动压区临时支护技术和碎石帮挡矸护巷技术;不同煤厚条件下,采空区矸石的垮落状态和顶板覆岩的运动规律不同,从而决定了应采取不同的设计参数。

To explore a systematic key technical system for nonpillar mining with automatically formed entry by roof cutting and pressure release under different coal thickness conditions,a thin coal seam mining face of Hecaogou No.2 coal mine,a mediumthick coal seam mining face of Dianping Coal Mine and a thick coal seam mining face of Ningtiaota Coal Mine were taken as the engineering background,the key design parameters of roof cutting and roof support were studied and on-site engineering tests were carried out.The research showed that the effects of roof cutting and roof support are the key to ensure successful implementation of the new technique.The key technologies can be summarized as the directional roof cutting technology,NPR constant resistance anchor cable support technology,temporary support technology in dynamic pressure area and gangue prevention technology.Under different coal thickness conditions,the movement state of the gangue in the gob area and the movement laws of the roof overburden were different,which determines that different technical parameters should be adopted.