Zhang Pei, Li Zhuo, Wei Yibo, Chen Yang, Dong Liqiang
College of Energy Engineering, Xi'an University of Science and Technology, Xi'an, 710054, China.
Sci Rep. 2025 Feb 13;15(1):5324. doi: 10.1038/s41598-025-89808-1.
In view of the feasibility of upward mining under the influence of repetitive mining for the close-proximity gently inclined coal seams, combined with the engineering geology of the coal seams in the south area of Xin'an Coal Mine, a formula for the depth of rock mass failure above the working face roof was proposed to investigate the continuity and integrity of coal seams 2 after the mining of the underlying coal seams. The characteristics of the overlying rock collapsed and the deformation law of the rock stratum sinking were analyzed through the similar experiments of physical simulation, to prove whether or not it is technically feasible to mine upward for the coal seams. Numerical simulation software is used to simulate the spatial distribution of mining stress field and stress transfer law of rock layer in the process of coal seams mining. The study shows that coal 2 is located within the lower coal seam fissure zone. The rock layer at the bottom of the working face has a certain bearing capacity, and can still maintain good continuity under the influence of repetitive mining. The stress concentration area of coal 3 up-slope mining develops continuously to the upper left rock body, and the peak of stress concentration is getting closer and closer to the coal wall, and the stress of coal 2 bottom plate and coal 2 top plate does not fall back significantly after the peak of stress occurs. The degree of rock fall and damage after mining is small, meeting the conditions required for upward mining. The results of the study provide a reference for the analysis of overburden structure and feasibility assessment under similar coal seams upward mining conditions.
针对近距离缓倾斜煤层重复采动影响下上行开采的可行性，结合新安煤矿南区煤层的工程地质条件，提出了工作面顶板上方岩体破坏深度公式，以研究下伏煤层开采后2号煤层的连续性和完整性。通过物理模拟相似实验，分析了覆岩垮落特征和岩层下沉变形规律，论证了煤层上行开采的技术可行性。利用数值模拟软件对煤层开采过程中采动应力场的空间分布及岩层应力传递规律进行了模拟。研究表明，2号煤位于下煤层裂隙带范围内，工作面底部岩层具有一定承载能力，在重复采动影响下仍能保持较好的连续性。3号煤上坡开采应力集中区不断向上左岩体发展，应力集中峰值越来越靠近煤壁，应力峰值出现后，2号煤底板和2号煤顶板应力回落不明显。开采后岩层垮落破坏程度较小，满足上行开采所需条件。研究结果为类似煤层上行开采条件下覆岩结构分析及可行性评价提供了参考。
