不同断层倾角下煤系断层应力场演化规律研究  

Study on evolution law of fault stress field in coal measures at different fault dips

作　　者：石佳林 胡千庭[1,2] 罗永江[1,2] 廖志伟 刘齐 王晓东[1,2] SHI Jialin;HU Qianting;LUO Yongjiang;LIAO Zhiwei;LIU Qi;WANG Xiaodong(State Key Laboratory of Coal Mine Disaster Dynamics and Control,Chongqing University,Chongqing 400044,China;School of Resources and Safety Engineering,Chongqing University,Chongqing 400044,China)

机构地区：[1]重庆大学煤矿灾害动力学与控制国家重点实验室,重庆400044 [2]重庆大学资源与安全学院,重庆400044

出　　处：《矿业安全与环保》2023年第1期1-8,共8页Mining Safety & Environmental Protection

基　　金：国家重点研发计划项目(2016YFC0801402-1);中央高校基本科研业务费项目(2021CDJQY-028)。

摘　　要：为深入了解煤系断层构造带应力场演化特征,以重庆石壕煤矿为例,通过物理相似模拟研究不同倾角断层在水平应力作用下破坏形态及内部的应力变化规律,同时结合数值模拟软件PFC分析不同断层倾角下应力增高区范围与断层破坏的影响。结果表明:断层倾角较小时发生滑动破坏,随着倾角的增大,断层两端应力无法通过滑动卸载,破坏形式逐渐变为剪切破坏;加载时断层下盘区域产生应力集中,断层倾角增大使得应力增高区因不同的破坏形式从下盘煤层区域向下盘顶、底板区域转移;通过PFC数值模拟,可以有效观测到模型内部裂缝,并对试件内部微裂缝进行考察研究与物理试验有着较好的一致性;通过力链分析发现,断层倾角变化会诱使应力增高区从煤层过渡到力学性能较强的顶、底板。In order to further understand the evolution characteristics of stress field in fault tectonic zone of coal measures, taking Shihao Coal Mine in Chongqing as an example, the failure mode and internal stress variation law of faults with different dips under horizontal stress were studied by physical similarity simulation. At the same time, the influence of stress-concentrated area and fault failure at different dips was analyzed by combining with numerical simulation software PFC. The results show that sliding failure occurs when the dip of fault is small. With the increase of dip, the stress at both ends of the fault cannot slip unloading, and the failure form gradually changes to shear failure. The stress concentration occurs in footwall area of fault during loading, and the increase of dip will make the stress-concentrated area transfer from footwall seam area to footwall floor area due to different failure forms. Through PFC numerical simulation, internal cracks can be effectively observed, which not only has a good agreement with the physical experiment, but also investigates the internal microcracks of specimens. Through force chain analysis, it is found that the change of fault dip will induce the stress-concentrated area to transition from coal seam to roof and floor with strong mechanical properties.

关 键 词：断层倾角 破坏形态 应力场演化 应力增高区 数值模拟 力链 

分 类 号：TD82[矿业工程—煤矿开采] P554[矿业工程—矿山开采]