8.5 m大采高综采工作面煤壁片帮特征研究

Study on rib spalling characteristics of 8.5 m height fully mechanized mining face

为解决8.5 m大采高综采工作面煤壁片帮严重的问题,以上湾煤矿12401首采工作面为研究对象,采用理论分析、经验回归分析、数值模拟手段,对煤壁片帮的主要影响因素与煤壁片帮特征进行研究,提出了基于D-P准则引入洛德参数修正塑性区宽度计算公式,并以采高、塑性区宽度和现场实测场数据为基础,由经验回归分析法综合预测出煤壁片帮深度。结果表明:神东矿区综采工作面煤壁片帮主要影响因素为支承压力、采高、周期来压和埋深,综合确定上湾煤矿12401综采工作面煤体塑性区宽度为9.87 m,煤壁主要发生剪切破坏、易失稳位置距顶板2.98~3.57 m,片帮深度约2.85~3.45 m,综合分析法得到的片帮深度是可靠的,可为支架护帮板设计提供依据,并相应采取合理的防片帮措施。

In order to solve rib spalling problem of 8. 5 m height fully mechanized face,main influence factors and characteristics of No.12401 working face in Shangwan Coal Mine were studied through theoretical analysis,empirical regression analysis and numerical simulation methods.Plastic zone width formula was established based on D-P criteria modified by the Lord parameter. The rib spalling depth was determined by regression analysis based on mining height and plastic zone width. The results showed that in Shendong Mining Area,main influence factors of rib spalling were bearing pressure,mining height,periodic weighting and mining depth. The main failure form of No.12401 working face was shear failure type. For the working face,plastic zone width was 9.87 m,instable position was from 2.98 m to 3.59 m to roof,the rib spalling depth was from 2.85 m to 3.45 m.The comprehensive analysis through the modified calculation formula of the plastic zone width,theoretical analysis,regression analysis can improve the reliability on the depth of coal wall spalling. These results can provide the basis for the design of the hydraulic support and selecting appropriate measures to prevent this phenomenon.