大埋深“三软”厚煤层智能综放开采技术研究

Intelligent fully mechanized top-coal caving technology for large-depth,“three-soft”, thick coal seams

针对大埋深“三软”条件下厚煤层综放开采的过程中液压支架钻底以及巷道底鼓的问题,以淮北信湖煤矿818智能综放工作面为研究背景,对液压支架的适用性进行了分析,并介绍了818智能综放采煤工作面的液压支架自动化系统。通过理论计算得出液压支架的最大工作阻力为9940 kN,分析现场实测数据可知中部液压支架的工作阻力最高,其次是下部,上部最小。工作面支架前排立柱受力大于后排立柱,工作面来压时,液压支架前立柱工作阻力平均比后立柱工作阻力大44.5%,前排立柱工作阻力占整架工作阻力的比例大致在0.57~0.74之间,工作面液压支架平均工作阻力为28.11 MPa,因此动载荷计算法更适合818工作面支架工作阻力计算;分析了液压支架钻底的原因,并提出液压支架的管控措施;通过数值模拟得到工作面超前支承压力的影响范围为煤壁前方110 m,工作面中部峰值应力最大,其次是下部,最后是上部,峰值应力出现在煤壁前方12~19 m;由现场实测数据可知煤壁向外105 m范围内,巷道底鼓及两帮变形量相对较大,巷道顶板下沉及底鼓比较明显,在此基础上提出预防巷道底鼓的相关措施,以期为淮北矿区以及类似条件下开采的工作面提供借鉴与参考。

Aiming at the hydraulic support sinking and roadway floor heave during fully mechanized mining for deep,thick,"three-soft"seams,taking No.818 intelligent fully mechanized face at Xinhu Coal Mine,Huaibei City,as the research background,the applicability and automatic system of hydraulic supports in No.818 intelligent mining face is analyzed and introduced.Through theoretical calculation,the max working resistance of the hydraulic support is 9940 kN.By analyzing the measured data in the field,it can be seen that the working resistance of the hydraulic support in the middle is the highest,followed by the lower part,and the top part is the smallest.The working resistance of the front column of the working face is larger than that of the rear column,during the working face weighting,the working resistance of the front column of the hydraulic support is 44.5%larger than that of the rear column on average,the ratio of the working resistance of the front column to that of the whole frame is roughly in the range of 0.57 to 0.74,and the average working resistance of the hydraulic support in the working face is 28.11 MPa.The method of calculating dynamic load is more suitable for calculating the working resistance of the hydraulic support in the working face of No.818.The reasons for hydraulic support sinking are analyzed,and the control measures of hydraulic support are proposed.Through numerical simulation,the influence range of the advance abutment pressure in working face is 110 m in front of the coal wall,the peak stress shows in the middle of the working face,followed by the lower part,and then the upper part,and the peak stress occurs at 12~19 m in front of the coal wall.The actual measurement data show that in the range of 105 m outward of the coal wall,the floor heave and the deformation of the two sides are relatively large,and the roof subsidence and floor heave are more obvious,based on which,the prevention measures for roadway floor heave is proposed to provide a reference for the working face in Huaibei mining area and similar conditions.