Coal Mining & Designing Department, Tiandi Science & Technology Co., Ltd. Coal Mining Damage Technical
Appraisal Comitte, China Coal Society Shanxi Zhongmei Dongpo Coal Co., Ltd. Coal Industry Jinan Design &
Research Co., Ltd.

为研究黄土沟壑区近浅埋深特厚煤层综放开采一次性采全高地质采矿条件下的地表裂缝发育规律,根据试验工作面实测地表裂缝发育特征,研究了该地质采矿条件下的地表裂缝形成机理及反向台阶形成原因,分析了试验工作面顶板垮落的周期性特征,推导了工作面开采对地表的拉裂缝发育影响范围与剪裂缝发育影响范围的理论计算公式。研究结果表明:工作面推进速度变化、综放开采放出煤层厚度变化与地貌和地质应力的影响是地表反向台阶裂缝形成的特殊原因;工作面沿走向方向地表裂缝间距具有与直接顶板周期性破断步距相近的发育规律;推导出的地表拉裂缝与剪裂缝发育影响范围的理论计算公式,可用于工作面开采对地表建筑物的裂缝危害范围预计与判断。

In order to study law of surface cracks under situation of loess hilly- gully region and middle thick bedrock in extra thick seam using fully- mechanized to p coal caving method, according to surface cracks data of the test area working face, the authors studied special reason for formation of reversed steps- like cracks and formation mechanism of surface cracks, and analysed periodic characteristics of roof caving, and deduced calculation formula of influence scope for tensile cracks and shear cracks. Results showed that rate change of working face, thickness change of top coal caving and influence of land form and geological stress were the specific r easons for formation of reversed steps- like cracks. Cracks spacing along strike direction and periodic weighting interval of immediate roof were close. The calculation f ormula of influence scope for tensile cracks and shear cracks had a guiding significancefor predicting surface crack damage scope of mining under buildings.

国家科技重大专项资助项目(2011ZX05064)；