In China, there exist significant volumes of coal resources that remain stranded above the goaf areas of close-distance multiple coal seams. The primary challenge in mining these coal seam groups lies in assessing the extent of disturbance and damage caused by repeated mining activities on residual seams, as well as in mastering the structural characteristics and deformation patterns of the overlying strata. The long-term practical experience of coordinated mining in the Kailuan Mining Area was grounded upon, and traditional discrimination methods for upward mining, including the relationships between mining height and interlayer spacing, and among burial depth, interlayer spacing, and mining height, were drawn upon. Based on key factors such as the distribution of coal-bearing strata, interlayer interactions, mechanical properties of rock strata, and mining-induced failure, the concept of “upward mining feasibility” was proposed for the first time, and a quantitative approach and evaluation system for assessing this feasibility were established. The method was applied to generate a feasibility cloud map for the upward mining of the No.9 coal seam based on geological data from the Qianjiaying Mine. The development degree of fractures and the fracturing condition of the overlying strata and the floor of the No.9 coal seam were measured in situ through borehole inspection and ground penetrating radar detection. The results indicate that after mining the No.12 coal seam, the caving zone ranges from 15.4 to 21.2 m, and the overall subsidence of the overlying strata in the observation section ranges from 0.1 to 0.4 m. The No.9 coal seam remains continuous, which further verifies the feasibility of upward mining. During the mining of panel 1692 of the No.9 coal seam, mine pressure monitoring data indicate relatively low roof stress, with no significant periodic weighting observed. The average utilization rate of the support load is 59%, reflecting a generally low level of support load utilization. The extraction of the No. 9 coal seam yields favorable results. Consequently, the feasibility assessment method provides a new basis for the upward mining of coal seam groups.
LEI Ming-xing, ZHANG Peng, LI Yang, ZHANG Yan-bo.
Coordinated Mining for Close Coal Seam Groups Based on Assessment of Upward Mining Feasibility[J].
Science Technology and Engineering, 2026, 26(26): 11256-11265 DOI:10.12404/j.issn.1671-1815.2507272
JiangJinquan, SunChunjiang, YinZengde, et al. Study and practice of bottom slicing relieving mining in condition of trouble coal seams with high ground stress under deep coal mine[J]. Journal of China Coal Society, 2004, 29(1): 1-6.
[7]
冯国瑞. 残采区上行开采基础理论及应用研究[D]. 太原: 太原理工大学, 2009.
[8]
FengGuorui. Study on the theory and its application of upward mining of left-over coal[D]. Taiyuan: Taiyuan University of Technology, 2009.
FengGuorui, YanXu, WangXianxia, et al. Determination of key position of strata controlling in rocks between coal seams for upward mining[J]. Chinese Journal of Rock Mechanics and Engineering, 2009, 28(S2): 3721-3726.
FengGuorui, RenYafeng, WangXianxia, et al. Experimental study on the overmining of the left-over coal above gob area mined with caving method in Baijiazhuang Coal Mine[J]. Journal of China Coal Society, 2011, 36(4): 544-550.
FengGuorui, YanYonggan, YangShuangsuo, et al. Analysis on the damage zone of overlying strata and safety layer distance on the overmining above the longwall goaf[J]. Journal of China Coal Society, 2009, 34(8): 1032-1036.
LiYang, LeiMingxing, ZhenQingxue, et al. Quantitative criterion on coordinated ascending mining in close multiple “thin-medium-thick” coal seams[J]. Journal of China Coal Society, 2019, 44(S2): 410-418.
LiYang, RenYuqi, LiTiezheng, et al. Calculation and system of support resistance of shield for contugous-multiple coal seams with coordinated mining[J]. Coal Science and Technology, 2023, 51(7): 268-277.
LiYang, RenYuqi, WangNan, et al. Structure form and evolution characteristics of collapsed roof in goaf[J]. Journal of China Coal Society, 2021, 46(12): 3771-3780.
ChengZhiheng, QiQingxin, LiHongyan, et al. Evolution of the superimposed mining induced stress-fissure field under extracting of close distance coal seam group[J]. Journal of China Coal Society, 2016, 41(2): 367-375.
LiLiang, HeFulian, XuXunhui, et al. Study on the evolution of stress arch shape and abutment pressure distribution in close distance coal seams[J]. Journal of Mining & Safety Engineering, 2023, 40(2): 295-303.
YangYaochi, ZhaoGuozhen. Failure characteristics and stress transfer rule of overburden under multiple mining in contiguous coal seams[J]. Coal Engneering, 2024, 56(3): 110-116.
LiShugang, DingYang, AnChaofeng, et al. Experimental research on the shape and dynamic evolution of repeated mining-induced fractures in short-distance coal seams[J]. Journal of Mining & Safety Engineering, 2016, 33(5): 904-910.
HanJun, ZhangHongwei, ZhangPutian, et al. Feasibility study on overmining in seam group with short distance to each other in Kailuan Mining Area[J]. Coal Science and Technology, 2011, 39(10): 14-17.
ZhongHongwei, HanJun, HaiLixin, et al. Study on closed multiple-seam in the ascending mining technology[J]. Journal of Mining & Safety Engineering, 2013, 30(1): 63-67.
HuangQingxiang, ZhaoMenghua, HhuangKejun. Study of roof double key strata structure and support resistance of shallow coal seams group mining[J]. Journal of China University of Mining &Technology, 2019, 48(1): 71-77, 86.
HouYunbing, HeShangsen, XieShengrong. Damage and rupture laws of main roof between coal seams with a close distance[J]. Rock and Soil Mechanics, 2017, 38(10): 2989-2999, 3008.
LiuHongtao, HanZhou, HanZijun, et al. Research on the distribution law of downward mining stress field in close-distance coal seam and reasonable location of the roadway[J]. Coal Science and Technology, 2024, 52(5): 1-10.
ZhangXiangyang, RenQihan, TuMin, et al. Fracture evolution characteristics of surrounding rock during ascending mining of closer coal seam in Panyidong Coal Mine[J]. Journal of Mining & Safety Engineering, 2016, 33(2): 191-198.
CaoJian, SuHaitao, WangChao, et al. Fracture activation in the overburden and aquiclude stability under the mining of close-distance coal seams[J]. Coal Geology & Exploration, 2025, 53(4): 153-167.
FuZizhao, BaiJianbiao, YanShuai, et al. Stress superposition characteristics and roof structure control of recovery room in close distance coal seam[J]. Coal Science and Technology, 2025, 53(6): 383-395.
ChengHui, ZhaoHongbao, ZhangHuan, et al. Reasonable coal pillar setting and roadway surrounding rock control technology in close-distance coal seam working face[J]. Chinese Journal of Engineering, 2022, 44(7): 1147-1159.
JiangQiangqiang, XuYangqing, WangHongfei, et al. Safety analysis of tunnel engineering in old goaf of coal seam[J]. Science Technology and Engineering, 2025, 25(26): 11358-11369.