College of Energy and Mining Engineering, Shandong University of Science and Technology
State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology, Shandong University of Science and Technology
Graduate School of Engineering, Kyushu University
School of Mining Engineering, University of Science and Technology Liaoning

为研究煤系断层形成及其对采动灾害的影响规律，改进了煤系逆断层形成模拟试验系统，采用液压伺服控制实现位移和应力双重精确控制，煤层开采试验时只拆卸煤层后方回采位置部分透明板，保持内部构造应力不被释放，利用该系统进行了煤系逆断层形成与开采试验研究。结果表明：逆断层形成过程中各岩层位移可划分为3个区域：位移区、压缩区、稳定区；位移区绝对位移最大，相对位移较小，其范围随岩层埋深减小而增大；压缩区自上盘向下盘绝对位移逐渐减小，相对位移逐渐增加；稳定区绝对位移与相对位移均最小，其范围随岩层埋深减小而减小；上盘测点位移角随着测点与断层距离的减小逐渐增大，最大达到87.5°；逆断层形成过程中顶、底板水平应力呈先增大后减小的规律，且上盘水平应力大于下盘；断层下盘顶板垂直应力呈上升趋势，上盘煤层顶板垂直应力呈增大—减小—增大的变化趋势；对比分析国内22处煤系逆断层地应力实测数据表明，逆断层构造区域最大水平主应力和垂直主应力比值k主要集中在1～4，本文试验中断层稳定后上、下盘k值稳定于2～3；煤系逆断层形成后下盘煤层回采过程中，顶板垂直应力与水平应力均呈先增大后减小趋势，近断层岩层在构造应力与采动应力相互叠加作用下产生应力积聚，其峰值应力更高，导致回采后上覆岩层运动更剧烈；工作面向断层方向推进可分为矿压周期演化阶段和动力灾变阶段，在矿压周期演化阶段，煤壁及工作面上方的垂直应力呈周期性显著增加，高应力区域向下盘构造煤迁移，动力灾变阶段中工作面已处于高应力区域，在断层活化的影响下易引发冲击地压等煤矿动力灾害。

In order to better understand the formation of thrust fault in coal measures and how it makes a difference on mining-induced disasters, a simulation system for the formation process of a new type of thrust fault in coal measures has been improved, which adopts hydraulic servo control to realize the double precise control of displacement and stress. During the coal seam mining test, only part of the transparent plate at the mining position behind the coal seam is removed to keep the internal structural stress from being released. The system is used to carry out the experimental research on the formation of thrust fault in coal measures and coal winning operation. The results indicate that the displacement of each rock stratum can be divided into three regions during the formation of thrust fault: displacement region, compression region and stability region. The maximum displacement of the measuring point is in the displacement region and the relative displacement in various measuring points is small, its extents increase with the decrease of the burial depth of rock stratum. The displacement of measuring points in the compression region gradually decreases from hanging wall to footwall, and the displacement and relative displacement in the stability region are both the smallest, and their extents decrease with the burial depth of the rock stratum. The displacement angle of hanging wall measuring point increases gradually as the measuring point approaches the fault plane, reaching a maximum of 87.5°. In the formation of thrust fault, the horizontal stress on the roof and floor increases and then decreases, and the horizontal stress on the hanging wall is greater than that at the foot wall. The vertical stress of the coal roof in the foot wall of the fault tends to increase, while the vertical stress of the coal seam roof in the hanging wall of the fault tends to present the change of increase−decrease – increase. When comparing and analyzing the in-situ stress measurements of 22 domestic thrust faults in coal measures, it suggests that the ratio of maximum horizontal principal stress to vertical principal stress is in the range of 1−4 in the tectonic zones of thrust fault. After the thrust fault is stabilized in the test, the k of the hanging wall and foot wall is stable between 2−3. After the formation of thrust fault in coal measures, in the footwall coal seam mining process, the vertical and horizontal stresses in the coal seam roof both tend to increase and then decrease. Under the superposition of tectonic stress and mining-induced stress, the rock stratum near the fault produces stress aggregation, and its peak stress is greater. The conditions mentioned above lead to more violent movement of the overlying strata after coal winning. The coal winning can be divided into the cyclic evolution stage of rock pressure and the dynamic disaster stage. In the cyclic evolution stage of rock pressure, the vertical stress of wall and working face increases significantly periodically, and the high stress area migrates to the footwall structure coal. In the dynamic disaster stage, the working face is already in high stress area, which is easy to cause coal mine dynamic disasters such as rock burst.

国家自然科学基金资助项目(51774194，52074169，52174159)

陈绍杰，张鑫源，石瑞明，等. 煤系逆断层形成过程及其对采动灾害的影响规律[J]. 煤炭学报，2023，48(8)：2995−3008.

CHEN Shaojie，ZHANG Xinyuan，SHI Ruiming，et al. Formation process of thrust faults in coal measures and its influence on mining disaster[J]. Journal of China Coal Society，2023，48(8)：2995−3008.