厚表土薄基岩煤层综放开采矿压显现规律

为解决司马矿厚表土薄基岩煤层的综放开采问题，采用理论分析、数值模拟、现场观测的方法对基岩结构稳定性和矿压显现规律进行了研究．结果表明，当其它条件不变，黏土层是薄基岩结构稳定性的重要影响因素，黏土层厚度越大则结构越稳定；工作面前方支承压力分布范围为15m，支承压力峰值点在工作面前方5～15m范围内，比厚基岩工作面小，基本项来压断裂步距小，但工作面矿压显现明显；当黏土厚40m，基岩厚20m时两者可形成较为稳定的结构．结论在现场首采工作面的开采试验中得到了验证．

Strata Behavior of Fully-Mechanized Top Coal Caving in Thin Bedrock and Thick Topsoil

In order to solve the problem of fully-mechanized top coal caving in thin bedrock and thick topsoil in Sima coal mine, the stability of bedrock structure and strata behavior rules were theoretically studied and numerically simulated based on in-situ measurement. The results indicate that the clay is the key factor affecting the stability of bedrock structure when other conditions keep unchanged. The thicker the clay is, the more stable the structure will be. The abutment pressure distribution ranges within 15 m from the working face and its peak value ranges from 5 m to 15 m, which is shorter than that in thick bedrock. The main roof periodic weighting breaking distance is short, but the strata behavior is quite distinctive in working face. a stable structure will be formed when the clay thickness reaches 40 m and the bedrock thickness reaches 20 m. This conclusion has been proved successful by the mining experiment in the first coal mining face of Sima coal mine.