摘要
针对新疆准东二矿1101工作面,通过分析现场矿压和微震数据,研究了综放工作面矿压显现规律以及顶板破坏特征和矿压显现之间的关系。研究结果表明:(1)准东二矿特厚煤层弱胶结顶板1101首采工作面基本顶初次来压步距为43.37 m,关键层初次来压步距为81 m,基本顶和关键层交替破断形成大小周期来压,大周期来压步距为30~40 m,小周期来压步距为18~22 m。(2)截止到工作面推进至270 m,小能量微震事件主要发生在顶煤中,大能量微震事件主要发生在关键层及以上岩层,微震能量大小呈现周期性变化,顶板裂隙发育高度为距离煤层顶板258 m左右。(3)压架事故发生在基本顶和关键层周期来压阶段,压架事故往往伴随大能量微震事件的发生。(4)综放工作面顶板形成“组合悬臂梁-铰接岩块”平衡结构,组合悬臂梁断裂形成小周期来压,关键层断裂同时压断下方悬臂梁形成大周期来压,然而弱胶结顶板使得关键层破断后不易形成稳定的铰接结构,破断岩块发生滑落失稳,对工作面造成冲击动载荷,造成压架事故的发生。在此基础上,提出了提高液压支架初撑力至31.4 MPa,控制工作面推进速度在5 m/d左右的防治措施。
Aiming at 1101 working face of Xinjiang Zhundong No.2 coal mine.By analyzing the field mine pressure and microseismic data,the law of mine pressure in fully-mechanized caving face and the relationship between roof failure characteristics and mine pressure appearance are studied.The results show that:(1)The first weighting step distance of the basic roof of the 1101 first mining face in the ultra-thick coal seam of Zhundong No.2 coal mine is 43.37 m,and the first weighting step distance of the key stratum is 81 m.The basic roof and the key stratum alternately break to form large and small periodic weighting.The large periodic weighting step distance is 30-40 m,and the small periodic weighting step distance is 18-22 m.(2)As the working face advances to 270 m,small microseismic energy events mainly occur in top coal,and large energy microseismic events mainly occur in key strata and above strata.The microseismic energy varies periodically,and the height of roof fracture development is about 258 m from the roof of coal seam.(3)The support crushing accident occurs in the periodic weighting stage of the main roof and the key stratum,and the support crushing accident is often accompanied by the occurrence of large-energy microseismic events.(4)The roof of the fullymechanized caving face forms a"combined cantilever beam-articulated rock block"equilibrium structure.The fracture of the combined cantilever beam forms a small periodic weighting,and the fracture of the key layer simultaneously breaks the cantilever beam below to form a large periodic weighting.However,the weakly cemented roof makes it difficult to form a stable articulated structure after the key layer is broken.The broken rock block slips and loses stability,which causes impact dynamic load on the working face and causes the occurrence of crushing accidents.On this basis,the prevention and control measures are put forward to improve the setting load of hydraulic support to 31.4 MPa and control the advancing speed of working face to about 5 m/d.
作者
彭宝山
王永乐
杨学孟
PENG Baoshan;WANG Yongle;YANG Xuemeng(Zhundong No.2 Coal Mine,CHN Energy Shendong Electric Power Group Co.,Ltd.,Changji 831800,China;School of Energy and Mining Engineering,China University of Mining and Technology-Beijing,Beijing 100083,China;State Grid Energy Xinjiang Zhundong Coal Power Co.,Ltd.,Changji 831800,China)
出处
《煤炭技术》
CAS
2024年第10期75-80,共6页
Coal Technology
关键词
特厚煤层
弱胶结地层
综放开采
矿压特征
强矿压机理
extra-thick coal seam
weakly cemented strata
fully-mechanized caving mining
characteristics of mine pressure
mechanism of strong mine pressure
