浅埋深薄基岩中厚煤层矿压显现规律

Strata Behavior Law of Medium Thick Coal Seam with Shallow Depth of Thin Bedrock

针对浅埋深薄基岩中厚煤层矿压显现规律问题,采用UDEC数值模拟软件和现场实测2种方法对李家壕煤矿3-1煤层的矿压规律显现进行研究。研究表明,工作面初次来压步距20m,周期来压步距10 m;周期来压期间,来压猛烈,历时短,工作面中部相对于两端部来压大,来压早,持续时间长;工作面前方支承压力集中不明显,影响范围较小;工作面发生台阶下沉,顶板破断运动波及地表,工作面上覆岩层中只存在垮落带和裂隙带"两带",不存在弯曲下沉带;顶板岩梁在工作面推进方向上传递载荷的能力大大下降。数值模拟结果和现场实测数据基本吻合。

Aiming at the problem of strata behavior Law of medium thick seam with shallow depth of thin bedrock, the article studies strata behavior law for 3 - 1 coal seam of Lijiahao Coal Mine with UDEC numerical simulation software and field test two methods. Studies show that the first weighting step distances is 20 m, periodic weighting step distances is 10 m. During periodic pressure period, the pressure is intense, short duration, the central pressure was large, early, long duration relative to both ends of the face ; the abut- ment pressure in front of work face was not obvious, the smaller sphere of influence ; face occurred stairs sinking, floor breaking movement spreaded to the top of the surface, the working face overburden only exists caving zone and fractured zone “two zone”, there is no curve subsidence zone. Strata roof beam greatly decreased ability to transfer load in the direction of face advancing. The numerical resuits and field data are consistent.