摘要
针对深埋超长工作面缺少采动底板破坏深度实测数据的问题,采用现场试验方法,分别对城郊煤矿二水平深部超长工作面断层部位、完整煤层底板进行了应力、水压力、应变感应测试。在典型21105工作面布置2个测孔分别用于底板扰动破坏监测,断层部位底板垂深10.5~11.5m分别埋设1个应变、应力传感器、水压力传感器,监测测点采前65m至采后42m;完整煤层底板垂深18.0~32.0m分别埋设4个应变传感器、1个应力传感器,监测测点采前55m至采后52m,获得了采动底板扰动破坏深度的实测数据。试验结果表明:该工作面断层附近超前40m已受到剧烈的采动影响,采动扰动深度远远大于10.5m,水压力、附加应力均呈先增大然后逐渐减小变化规律,说明围岩受采动影响后产生了裂隙,但影响很小;完整煤层附近测点5、测点4应变感应增量变化幅度分别达15779με、12023με,测点3、测点1应变感应程度相对较弱,整个观测过程基本保持了正常的工作状态,测点2附加应力最大值仅为14MPa,说明工作面底板破坏深度为22.0~27.0m。测试数据为城郊煤矿深埋、超长工作面的水害治理方案设计提供了科学依据。
In view of the lack of measured data of mining floor failure depth in deep buried super-long working face,the stress,water pressure and strain sensing tests were carried out on the fault part of the second level deep super-long working face and the floor of intact coal seam in Chengjiao Coal Mine through field test.Two measuring holes were arranged on the typical 21105 working face for disturbance and failure monitoring of floor,respectively.A strain sensor,stress sensor and water pressure sensor were buried in the vertical depth of floor 10.5~11.5 m in the fault part,and the monitoring points ranged from 65 m before mining to 42 m after mining.Four strain sensors and one stress sensor were buried in 18.0~32.0 m vertical depth of complete coal seam floor,and the measured data of disturbance failure depth of mining floor were obtained from 55 m before mining to 52 m after mining.The experimental results show that the depth of mining disturbance is much greater than 10.5 m,and the water pressure and additional stress increase first and then decrease gradually,indicating that the surrounding rock is affected by mining,but the influence is very small.In the vicinity of intact coal seam,the increment range of strain induction at measuring point 5 and 4 is 15779μεand 12023με,respectively.The strain induction degree of measuring point 3 and 1 is relatively weak,and the normal working state is basically maintained during the whole observation process.The maximum value of additional stress at measuring point 2 is only 14 MPa.The failure depth of the working face floor ranges from 22.0~27.0 m.
作者
王伟
戴磊
段李宏
杨斌
WANG Wei;DAI Lei;DUAN Li-hong;YANG Bin(Yongmei Group Co.,Ltd.,Henan Yongcheng 476600,China)
出处
《煤炭工程》
北大核心
2022年第12期73-77,共5页
Coal Engineering
基金
国家自然科学基金面上项目(41972171)
关键词
超长工作面
采动影响
底板破坏深度
现场测试
应力监测
super long working face
mining influence
floor damage depth
field test
stress monitoring
