Study on overburden strata collapse law and deformation-failure prediction of mining-induced slopes
XIE Hui
WANG Yong
LI Qianhui
JIANG Xiaowei
GUI Jingjing
ZHU Tao
Abstract：Aiming at the disaster mechanism and cross-scale prediction problem of slopes with"hard at the top and soft at the bot-tom"structure under mining disturbance in the mountainous area of southwest China,this study takes the fifth panel of Fa'er Coal Mine in Guizhou Province as the research object to reveal the dynamic coupling mechanism of overburden strata collapse and slope deformation,and construct a disaster whole life cycle prediction technology system based on the coordination of space-air-ground.Based on 9 goaf areas with a total length of 850 m in 50106 mining area,a discrete element model with a height of 727 m and a width of 1 527 m was established by using the intergration method of discrete element numerical simulation,differential interfero-metric synthetic aperture radar(D-InSAR)small baseline subset(SBAS)time-series analysis technology(SBAS-InSAR)and field geological survey.15 displacement monitoring points were set up to simulate the dynamic excavation process.Through displace-ment field analysis,surface deformation inversion and field verification,the chain response law of"overburden strata collapse-fis-sure expansion-surface slip"is elucidated.The study quantitatively revealed the periodic expansion mechanism of"formation-ex-pansion-compaction closure"of mining overburden fracture,with the maximum roof settlement of 3.03 m and the peak surface hori-zontal displacement of 1.64 m.SBAS-InSAR monitoring shows that the high risk area with the maximum annual deformation rate of 44 mm/a overlaps significantly with the potential slip surface(elevation 950-980 m)predicted by numerical simulation.A five-stage geo-mechanical model including natural evolution,overburden strata collapse,slow deformation,progressive deformation and over-all instability is established.The fracture zone height reaches 20.5 m in the overburden strata collapse stage,0.15 m reverse displace-ment occurs in the slow deformation stage,and the displacement gradient reaches 1.2 m/hm in the progressive deformation stage.The results show that the simulated value of collapse zone height is 18-22 m,and the error between the simulated value and the measured value is less than 13%.The slope presents the characteristics of asymmetric displacement field,and the surface horizontal displacement gradient reaches 0.8 m/hm,which is 4 times that of the slope interior.The INSAR-UAV-numerical simulation collabor-ative early warning technology was constructed to divide the high,medium and low risk zones,among which the potential sliding surface instability volume in the high risk zone reached 900 m3.The mechanical transmission mechanism of"roof separation,ma-sonry beam fracture and slope extrusion"is studied,and the cross-scale disaster warning from kilometer-level goaf to centimeter-level surface deformation is realized through collaborative technology.
Keywords：geological hazardmining-induced slopeoverburden collapsesurface deformation and failurecross-scale disaster warningmulti-source technology
Publication Date：2025-11-20
Online Publishing Date：2025-11-25(First online date of this platform, not the publication date of the document)
Pages：12( 88-99 )