摘要
穿煤层不充水陷落柱赋存的覆岩在工作面推采陷落柱影响下会发生异常破坏,易形成顶板突水危害。为研究该类工作面覆岩的异常破坏规律,以经坊煤矿为工程背景,充分考虑陷落柱的形成及围岩地质特征构建了陷落柱-围岩裂隙模型,并在此基础上运用理论分析、相似模拟和数值模拟相结合的方法,研究了推采陷落柱工作面覆岩异常破坏规律。结果表明:覆岩中存在陷落柱围岩裂隙场和采动裂隙场,其裂隙分布各具特点;采动影响下,裂隙场发生耦合的同时陷落柱围岩裂隙场又产生新的变化,两者的综合作用使覆岩破坏呈现出新特点,工作面覆岩在陷落柱周围形成集中破坏,柱边新生的离层裂隙和纵向断裂裂隙可与两类裂隙场的裂隙相贯通,柱顶新生两类裂隙可相互贯通,致使陷落柱周围和顶部岩体贯通型裂隙增多,导水性增强,水灾危险性增大。
When the working face passes a non-water filled collapse column,the overlaying strata of the working face can be damaged abnormally owing to the mining influence,which inevitably induces water inrush disaster. To study the abnormal failure laws of overlaying strata,the Jingfang coal mine was chosen as the engineering background in the study. A collapse column-surrounding rock fissure mechanical model was built by fully considering the formation of collapse column and geological characteristics of its surrounding rocks. Based on this model,the abnormal failure laws of overlaying strata were analyzed theoretically by combination of physical and numerical simulations. The results indicate that collapse column-surrounding rock fissure field and the mining fissure field were existent in the overburden rock with their own fracture distribution features. Under the influence of mining,some new destruction features were developed under the action of coupled fracture fields and the variation of collapse columnsurrounding rock fissures. A concentrated destruction occurred around the collapse column. The new born fissures of bed-separated near the column side and longitudinal broken fissures were interconnected with the above two fissure fields. At the top of the column,the two types of new born fissures could be interconnected. The connected fissures around the collapse column and top of rock mass gradually increased,which caused the hydraulic conductivity to be enhanced and the risk of water-inrush from roof to be increased.
出处
《矿业科学学报》
2018年第3期268-276,共9页
Journal of Mining Science and Technology
基金
国家重点基础研究发展计划(973计划)(2013CB227903)
国家自然科学基金煤炭联合基金重点项目(U1361209)
关键词
陷落柱
相似模拟
数值模拟
覆岩裂隙
collapse column
physical simulation
numerical simulation
overlaying strata fissure