Study on failure mechanism of slopes induced by the underground coal mining subsidence
SUN Shuwei1, YANG Zhaoxi1, JIA Peizhi1, WANG Xiaolong1, LI Guojun2
(1. School of Energy and Mining Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China;
2. School of Safety Engineering, China University of Mining and Technology, Xuzhou, Jiangsu 221116, China)
Abstract：The underground mine workings induce movements in the overlying rock layers and alter stress fields, leading to the deterioration of rock properties in slopes, which can easily result in disasters such as slope landslides. This study compares the failure process of the underground mine-slope system under various underground mining conditions through bottom friction tests and numerical simulations. Consequently, the failure modes and deformation mechanisms of the slope influenced by underground coal mining subsidence were analyzed. The findings are as follows: (1) The effects of underground coal mining subsidence on slopes primarily include a reduction in the integrity and strength of the slope rock mass, a change in the inclination angle of the slope rock layer, an enhancement of the tensile effects on the slope surface resulting in cracking, and a modification of the geometric shape of the slope. (2) The fracture mechanism of the overlying rock strata involves the gradual bending and collapse of the strata towards the underground mine workings due to gravitational forces. The fracture surface of the rock strata develops in a geese-like pattern, with the centerline of the underground mine workings serving as the axis of symmetry in the deeper field, and is connected to the tensile fractures on the slope surface in the near-slope field. (3) The mechanisms of slope failure induced by underground mine workings can be categorized into two types: compression-type and traction-type. Compression-type slope failure typically occurs in the lower slope of mining subsidence, and the process can be divided into stages such as overlying rock collapse, subsidence compression, and slope sliding. Conversely, traction-type slope failure usually occurs on the upper slope of mining subsidence, with the process divided into stages including the collapse of overlying rock strata, traction and tearing, and slope sliding. (4) The geological structure significantly influences the instability and failure processes of the overlying slope. When the rock layers of the slope are oriented in a bedding fashion, the fracture surface patterns on both sides of the overlying rock layer rotate towards the dip direction, resulting in a relatively large deformation and failure range of the slope induced by mining subsidence. In contrast, when the rock strata are in a reverse inclined orientation, the effect of underground mine workings at the same position and burial depth on the slope displacement is significantly reduced. The research results provide valuable insights for identifying slope disasters in coal mining subsidence areas and for ensuring safety in open-pit to underground mining transition projects.
孙书伟1，杨肇熙1，贾培智1，王晓龙1，李国君2. 煤矿地下采空区沉陷诱发边坡破坏机制研究[J]. 岩石力学与工程学报, 2025, 44(6): 1405-1419.
SUN Shuwei1, YANG Zhaoxi1, JIA Peizhi1, WANG Xiaolong1, LI Guojun2. Study on failure mechanism of slopes induced by the underground coal mining subsidence. , 2025, 44(6): 1405-1419.
VYAZMENSKY A，STEAD D，ELMO D，et al. Numerical analysis of block caving-induced instability in large open pit slopes：a finite element/discrete element approach[J]. Rock Mechanics and Rock Engineering，2010，43(1)：21-39.
[3]
CHEN L Q，ZHAO C Y，KANG Y，et al. Pre-event deformation and failure mechanism analysis of the Pusa landslide，China with multi-sensor SAR imagery[J]. Remote Sensing，2020，12(5)：856.
[4]
YIN Y P，SUN P，ZHANG M，et al. Mechanism on apparent dip sliding of oblique inclined bedding rockslide at Jiweishan，Chongqing，China[J]. Landslides，2011，8(1)：41-65.
[5]
WALTON G，TAYLOR R K. Likely constraints on the stability of excavated slopes due to underground coal workings[C]// Proceedings of the CORE UK Conference. [S. l.]：[s. n.]，1977：329-351.
[6]
WHITTAKER B N，REDDISH D J. Subsidence：occurrence，prediction and control[M]. Amsterdam：Elsevier，1989：257-271.
[7]
DO T N，WU J H，LIN H M. Investigation of sloped surface subsidence during inclined seam extraction in a jointed rock mass using discontinuous deformation analysis[J]. International Journal of Geomechanics，2017，17(8)：04017021.
[8]
孙世国，蔡美峰，王思敬. 露天转地下开采边坡岩体滑移机制的探讨[J]. 岩石力学与工程学报，2000，19(1)：126-129.(SUN Shiguo，CAI Meifeng，WANG Sijing. Study of sliding mechanism for slope due to the excavation from open pit into underground mine[J]. Chinese Journal of Rock Mechanics and Engineering，2000，19(1)：126-129.(in Chinese))
[9]
汤伏全. 采动滑坡的机理分析[J]. 西安矿业学院学报，1989，(3)：32-36.(TANG Fuquan. Mechanism analysis of landslides induced by underground mining[J]. Journal of Xi?an Mining Institute，1989，(3)：32-36.(in Chinese))
[10]
万战胜. 公路下伏采空区地表变形及处治范围研究[博士学位论文][D]. 西安：长安大学，2011.(WAN Zhansheng. Research on surface deformation and treatment range of highway mined-out area[Ph. D. Thesis][D]. Xi?an：Chang?an University，2011.(in Chinese))
[11]
李腾飞，李 晓，苑伟娜，等. 地下采矿诱发山体崩滑地质灾害研究现状与展望[J]. 工程地质学报，2011，19(6)：831-838.(LI Tengfei，LI Xiao，YUAN Weina，et al. Current status and prospects of studies on mechanism of landslide geohazards induced by underground mining[J]. Journal of Engineering Geology，2011，19(6)：831-838.(in Chinese))
[12]
EINSTEIN H. Physical modelling in rock mechanics and rock engineering[J]. Rock Mechanics and Rock Engineering，2024，57：10 187-10 204.
[13]
BRAY J W，GOODMAN R E. The theory of base friction models[J]. International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts，1981，18(6)：453-468.
[14]
ZHENG D，FROST J D，HUANG R Q，et al. Failure process and modes of rockfall induced by underground mining：A case study of Kaiyang Phosphorite Mine rockfalls[J]. Engineering Geology，2015，197：145-157.
[15]
梁 风，史文兵，钱孝龙，等. 山区平缓倾内采动斜坡变形破坏机制研究——以贵州普洒崩塌为例[J]. 自然灾害学报，2022，31(4)：190-200.(LIANG Feng，SHI Wenbing，QIAN Xiaolng，et al. Study on deformation and failure mechanism of gentle anti-dipped slope induced by mining in mountain area：A case study of the Pusa village rock avalanche of Guizhou[J]. Journal of Natural Disasters，2022，31(4)：190-200.(in Chinese))
[16]
ZHANG S，SHI W，YANG C，et al. Experimental evaluation of gentle anti-dip slope deformation and fracture network under the action of underground mining[J]. Landslides，2023，20(2)：381-408.
[17]
孙书伟，李 圆，杨晓锐，等. 不同岩层倾角顺倾层状岩质边坡破坏机制研究[J]. 岩石力学与工程学报，2024，43(7)：1 607-1 620. (SUN Shuwei，LI Yuan，YANG Xiaorui，et al. Study on the failure mechanism of rock slopes with dipped layered structures under various rock dip conditions[J]. Chinese Journal of Rock Mechanics and Engineering，2024，43(7)：1 607-1 620.(in Chinese))
[18]
刘大勇. 抚顺煤田地质灾害成因机理与预测分析研究[博士学位论文][D]. 沈阳：东北大学，2009.(LIU Dayong. Study on formation mechanism-prediction analysis of geologic hazards in Fushun coalfield[Ph. D. Thesis][D]. Shenyang：Northeastern University，2009.(in Chinese))
[19]
International Society of Rock Mechanics(ISRM). Basic geological description of rock masses[J]. International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts，1981，18：85-110.
[20]
SUN S W，HU J B，DENG A，et al. Comparative tests on the failure characteristics and mechanisms of slopes with curved surfaces[J]. Bulletin of Engineering Geology and the Environment，2023，82(9)：1-33.
[21]
王恭先，赵 甫. 煤矿地区的滑坡灾害及其防治技术[J]. 煤田地质与勘探，2018，46(2)：1-7.(WANG Gongxian，ZHAO Fu. Landslide disaster and its prevention and control technology in coal mining area[J]. Coal Geology and Exploration，2018，46(2)：1-7.(in Chinese))
[22]
孙书伟，陈冲，丁 辉，等. 微型桩群加固土坡稳定性分析[J]. 岩土工程学报，2014，36(12)：2 306-2 314.(SUN Shuwei，CHEN Chong，DING Hui，et al. Stability analysis of earth slopes reinforced with micropiles[J]. Chinese Journal of Geotechnical Engineering，2014，36(12)：2 306-2 314.(in Chinese))
[23]
孙书伟，庞 博，刘 流. 露天排土场不同排土工艺失稳机制对比试验研究[J]. 岩石力学与工程学报，2021，40(8)：1 713-1 726.(SUN Shuwei，PANG Bo，LIU Liu. Comparative tests on failure mechanisms of waste dumps of open-pit mines with different dumping methods[J]. Chinese Journal of Rock Mechanics and Engineering，2021，40(8)：1 713-1 726.(in Chinese))
[24]
孙书伟，庞 博，刘 流，等. 露天矿排土场土工格栅加固机制试验研究[J]. 岩石力学与工程学报，2022，41(11)：2 320-2 336.(SUN Shuwei，PANG Bo，LIU Liu，et al. Experimental research on reinforcement mechanism of geogrid in open-pit dump[J]. Chinese Journal of Rock Mechanics and Engineering，2022，41(11)：2 320-2 336.(in Chinese))
2025, Vol. 44 
