摘要
为正确确定煤层覆岩受采动变形与破坏范围,更好地了解煤层采动影响下覆岩视电阻率的变化及破坏发育特征,结合围岩的力学性质、岩性与采煤方法等因素进行综合分析,将覆岩分成塑性破坏区、弹塑性过渡区、弹性区3个不同的导电性区段,分别建立了煤层受采动影响下覆岩电性动态变化的正常与存在导水裂隙带的地电模型,并对模型进行正演模拟研究。结果表明:覆岩受采动引起其视电阻率显著变化,视电阻率异常区随回采工作面的推进而移动,且其范围随之加大,致使导水裂隙能与塑性破坏高阻区相连,反映在塑性破坏高阻异常范围和幅度的减小,预示着顶板可能出水;利用覆岩受采动电性变化规律,有利于更为准确的探测顶板水的赋存状态可保障工作面的安全开采。
In order to accurately determine the mining deformation and failure scope of the overburden strata above seam and better understand the apparent resistivity variation and failure development features of the overburden strata under the influences of the seam mining,in combination with the mechanics properties of the surrounding rock,lithology,mining method and other factors,a comprehensive analysis was conducted. The overburden strata were divided into three different electric conductivity sections,including a plastic failure section,e lastic-plastic transition section and elastic section. The geoelectric models of the overburden strata with normal electric property dynamic variation and existed water flow crack zone under the influences of the seam mining were established individually and a forward simulation study was conducted on the model. The results showed that affected by the mining,the apparent resistivity of the overburden strata was varied obviously and the apparent resistivity abnormal zone would be displaced with the forward advancing of the coal mining face. The scope of the abnormal zone would be increased with the coal mining face forward advanced. Thus the water flow cracks would be connected with the plastic failure and high resistance zone. When the plastic failure high resistance abnormal scope and range reduced,a water inrush from the roof could be predicted. Affected by the mining,the application of the overburden strata electric property variation law could be favorable to accurately detect the roof water deposition status in order to protect the safety mining of the coal mining face.
出处
《煤炭科学技术》
CAS
北大核心
2015年第5期122-125 105,105,共5页
Coal Science and Technology
关键词
采动影响
导电性
地电模型
视电阻率响应
电性变化
overburden strata
mining influences
electric conductivity
earth-electricity model
apparent resistivity response
eleetrica property variation
