摘要
为解决倾斜矿体回采后大倾角顶板和非对称空区可能引发的采空区支撑结构体变形及破坏失稳问题,以某石灰石矿非对称顶板-矿柱支撑结构体为研究对象,构建结构体承载力学模型,求解顶板挠曲变形值及矿柱安全系数,分析不同倾角、跨度比下顶板变形特征及矿柱失稳破坏模式,研究其协同承载机理。结果表明:顶板变形、矿柱失稳破坏模式受采空区倾角θ和跨度比λ的双重影响,顶板变形大小随着θ的增加表现为双增长率,与λ的关系伴随着θ的变化而变化。矿柱失稳破坏模式受θ的影响程度随着λ的增加而减小,当0°<θ≤30°时,矿柱主要为小偏心受压破坏;当θ=0°和30°<θ≤60°时,随着λ值的增加,矿柱破坏模式从大偏心受压破坏向小偏心受压破坏转变。顶板维系采空区稳定的能力随着θ的增加逐渐降低,矿柱维系采空区稳定的最优λ值随着θ的增加逐渐减小,矿柱约束顶板变形作用大小随着λ的增加而降低。数值模拟和工程实例验证了理论计算结果的可靠性,为地下空场法矿山安全开采提供一定的理论支撑。
To solve the deformation and failure instability of the support structure body,which may be triggered by the large dip roof and asymmetric goaf after mining of the inclined orebody.The asymmetric roof-pillar support structure body of a limestone mine was taken as the research object,a structure mechanical model was established,the flexural deformation value of roof and safety factor of pillar were solved,the deformation characteristics of roof and instability failure mode of pillar in different angles and span ratios were analyzed,and the collaborative bearing mechanism was studied.The results show that the deformation of roof and the instability failure mode of pillar are doubly influenced by the dip angleθand the span ratioλof the goaf,and the deformation value of roof shows a double growth rate with the increase ofθ,and its relationship withλis related toθ.The influence ofθon the instability failure mode of pillar decreases with the increase ofλ.When 0°<θ≤30°,the pillar is mainly small eccentric compression failure;Whenθ=0°and 30°<θ≤60°,the failure mode of pillar from large eccentric compressive failure to small eccentric compressive failure with the increase ofλ.The ability of the roof to maintain the stability of the goaf gradually decreases with the increase ofθ.The optimalλof the pillar to maintain the stability of the goaf gradually decreases with the increase ofθ.The effect of the pillar to restrain the deformation of roof decreases with the increase ofλ.The numerical simulation results and engineering examples verify the reliability of the theoretical calculation results,and provide some theoretical supported for the safe mining of underground open stope method.
作者
姜立春
李金柱
JIANG Lichun;LI Jinzhu(School of Civil Engineering and Transportation,South China University of Technology,Guangzhou 510640,China;Institute of Safety Science and Engineering,South China University of Technology,Guangzhou 510640,China)
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
2024年第1期329-343,共15页
The Chinese Journal of Nonferrous Metals
基金
国家重点研发计划资助项目(2022YFC2903802)
国家自然科学基金资助项目(51974135)。
