针对正常使用的煤层大巷群屡次发生冲击地压问题，采用现场探测、力学分析、数值模拟等 方法，基于时变特性揭示了煤层大巷群冲击地压机理，并提出了新的防治方法。 结果表明，中央大 巷构造区域，断层、褶曲、埋深等提供了高应力基础环境，服务周期长的大巷群围岩由于塑性区及破 碎区范围随时间的延长而扩大，相邻巷道间煤柱弹性区范围不断减小，变为拥有共同的弹性区，两 帮应力峰值随时间延长相互叠加，促使本来濒临临界状态的围岩应力达到准平衡状态，巷间煤柱静 载荷高度集中，同时巷道内悬空面积增大的顶板断裂，产生动载荷对煤柱静载荷扰动诱发冲击地压 启动;造成中央大巷巷间煤柱静载荷高度集中的根本原因是上覆厚硬顶板长梁式悬臂与下沉，并且 随时间变化不断加剧，直至断裂产生了诱发冲击的动载荷;提出该类冲击地压防治，应该针对煤层 上覆厚硬顶板人为致裂，使其长梁变短梁，从而不再具备悬臂功能，也使得其上覆载荷由硬传递变 为软传递，降低了压裂区域下方煤层的整体静载水平;压裂后坚硬顶板能及时垮落并充填采空区， 减小了顶板来压产生的集中动载，使动载效应减弱，冲击风险降低。 采用千米钻机进行目标岩层深 孔压裂试验，达到了降低巷道围岩载荷、防治冲击地压目的。

In view of the frequent occurrence of rock bursts in coal seam roadway groups at normal use，based on the time⁃varying characteristics， the mechanism of rock bursts in coal seam roadway groups is revealed by using the methods of field detection，mechanical analysis and numerical simulation，and a new prevention method is put forward. The results show that the structural area of central roadway，fault，fold and buried depth provide a high⁃stress basic environment. The superposition effect of the time⁃varying characteristics of the surrounding rock of the road⁃ way group with a long service cycle promotes the high concentration of the static load of the coal pillar between the roadway. The roof fracture with the increase of the suspended area in the roadway produces the dynamic load， which disturbs the static load of the coal pillar and induces the initiation of rock burst. The fundamental reason for the high concentration of static load of coal pillar between central roadways is the long beam cantilever and subsid⁃ ence of overlying thick hard roof slab，which intensifies with time until the fracture produces the dynamic load inducing impact. It is proposed that the prevention and control of this kind of rock burst should be aimed at the thick hard roof on the coal seam，which is artificially cracked to make its long beam become a short beam，so that it no longer has the cantilever function，and the overlying load changes from hard transmission to soft transmission. The deep hole fracturing test of the target rock stratum is carried out with a kilometer drill，which achieves the purpose of reduc⁃ ing the load of roadway surrounding rock and preventing rock burst.