薄基岩综放采场基本顶周期来压力学分析  

Mechanical analysis of periodic weighting of main roof in longwall top coal caving face with thin bedrock roof

作　　者：杜锋[1] 白海波[1] 黄汉富[1] 姜广辉[1] 

机构地区：[1]中国矿业大学深部岩土力学与地下工程国家重点实验室,江苏徐州221008

出　　处：《中国矿业大学学报》2013年第3期362-369,共8页Journal of China University of Mining & Technology

基　　金：国家自然科学基金项目(50974115);高等学校学科创新引智计划(B07028);江苏省研究生培养创新工程(CXLX12_0946)

摘　　要：以山西潞安矿业集团司马煤矿厚黏土层薄基岩厚煤层开采为研究背景,采用数值模拟、理论分析、现场实测等方法对薄基岩综放采场基本顶运动结构特征进行了研究,利用关键层理论对薄基岩进行了定义,并建立了厚黏土层薄基岩综放采场基本顶周期来压岩层破断的力学模型,分析了基本顶结构的稳定性.结果表明:厚黏土层薄基岩厚煤层开采时,由于采厚较大,采动影响范围加大,当基本顶岩层形成"砌体梁"周期性破断后,上覆载荷岩层迅速移动并波及至黏土层,黏土层内部形成"拱"平衡结构;在"拱"结构保护下,"砌体梁"只需承受上覆基岩和拱内土体的重量,并非上覆全部土层荷载,故不易发生滑落失稳;"拱"发育高度与土体自身性质有关,与基岩厚度的变化关系不大,一般拱高为16～22m.This study takes the thick coal seam mining under thick hardpan and thin bedrock roof in Sima Coal Mine of Lu＇an Group as a case in point.The movement characteristics of main roof in longwall top coal caving face with thin bedrock roof（LTCCFTBR） were studied in use of numerical simulation,theoretical analysis,in-site measurement,etc.The thin bedrock was defined by means of key stratum theory,and mechanical model of the periodic weigthting rock failure of main roof in LTCCFTBR was established,and the stability of the main roof was also analyzed.The results show that： when mining the thick coal seam of thin bedrock of thick hardpan,the mining influences a large area due to the larger mining height;after the main roof formes periodic failure of ＂masonry beam＂,the overlying load rock strata quickly moves and spreads to the hardpan,then the ＂arch＂ equilabrium structure is formed in this hardpan;under the protection of ＂arch＂ structure,masonry beam only bears the weight of overlying bedrock and soil mass within the arch,rather than the weight of all the overlying hardpan,so instability and backfall can not likely occour in the masonry beam.The developing height of arch is related to the mechanical properites of the soil mass,but has a less correlation to the heigth of bedrock,and a typical arch height is 16—22 m.

关 键 词：薄基岩 综放开采 基本顶 周期来压 厚黏土层 

分 类 号：TD323[矿业工程—矿井建设] TD823