基于主应力状态转换的采场底板突水机理分析  

Mechanism analysis of stope floor water inrush based on principal stress state transition

作　　者：董书宁 柳昭星 王皓 DONG Shuning;LIU Zhaoxing;WANG Hao(Xi'an Research Institute,China Coal Technology and Engineering Group,Xi'an,Shaanxi 710054,China;Shaanxi Key Laboratory of Prevention and Control Technology for Coal Mine Water Hazard,Xi'an,Shaanxi 710077,China)

机构地区：[1]中煤科工西安研究院(集团)有限公司,陕西西安710054 [2]陕西省煤矿水害防治技术重点实验室,陕西西安710077

出　　处：《采矿与安全工程学报》2023年第4期691-703,共13页Journal of Mining & Safety Engineering

基　　金：国家重点研发计划项目(2017YFC0804100);国家自然科学基金项目(52104240);陕西省自然科学基础研究计划青年项目(2022JQ-320)。

摘　　要：为揭示采场底板突水过程中主应力状态转换与水压共同作用机理,笔者采用理论分析、室内试验和数值计算等手段,研究了煤层底板采动应力扰动突水判据、饱和岩层损伤试验特征、主应力转换特征。结果表明:基于采动底板岩层扰动程度判别指标、底板起裂压力阈值判别指标和底板含水层失稳判别指标得到的采动底板突水判据阈值为1;底板灰岩试样损伤在卸压后存在明显的延迟效应,而在失稳时产生应力跌落现象;采空区前后底板最大主应力由水平应力转换为垂直应力。底板卸荷后,最大主应力又从垂直应力转换为水平应力。采动底板最大与最小主应力差值在不同深度呈现不同分布特征,但总体均增大,且集中在采空区前后煤壁附近。In order to reveal the mechanism of the interaction between the state transition of principal stress and water pressure during the process of water inrush from the floor of the stope,the paper studied the criteria of water inrush from coal seam floor caused by mining dynamic stress disturbance,the characteristics of saturated rock damage test,and the characteristics of principal stress transition by means of theoretical analysis,laboratory tests,and numerical calculations.The results show that the threshold value of water inrush criterion for mining floor is based on the criteria of disturbance degree of floor strata,threshold value of floor fracturing pressure and instability of floor aquifer;and the damage of limestone sample in the floor has an obvious delay effect after pressure relief,and the stress drop occurs when the sample is unstable;the maximum principal stress of the floor is converted from horizontal stress to vertical stress before and after the goaf.Although the different distribution characteristics between the maximum and minimum primary stresses of the mining floor vary depending on depth,it generally increases and is concentrated close to the front and back coal walls of the goaf.

关 键 词：底板突水 采动应力状态 应力路径 突水判据 

分 类 号：TD325[矿业工程—矿井建设]