摘要
针对浅埋近距离多煤层中间厚关键层破断呈现的大小周期来压现象,以神东补连塔煤矿上煤层采空区下大采高工作面为背景,采用现场实测与理论分析等方法对多煤层工作面厚关键层破断特征及矿压显现规律进行了研究。结果表明:多煤层中间厚关键层在矿山压力和自身弱面结构影响下将以分层方式垮落;根据关键层判别方法、钻孔岩芯和工作面矿压显现综合判断,垮落位置位于该岩层中部,上位厚关键层顶板形成"砌体梁"结构,下位厚关键层顶板形成"悬臂梁"结构;"砌体梁"结构对工作面矿压影响减弱,"悬臂梁"结构成为支架作用力的主要力源;正常回采时影响支架稳定的最危险状态是悬臂梁与砌体梁组合同时破断,对工作面顶板管理带来一定的困难;厚关键层在特殊情况下会产生整层破断形成"台阶岩梁"结构,应提前采取应对措施。
In view of the size of the weighting cycle phenomenon under the condition of middle thick key stratum broken in multiple coal seam mining gobs with shallow depth, this paper takes a panel of the Bulianta mine with a large mining height in Shendong coal field as the research background. The ground pressure behavior and roof movement characteristics of the thick key strata are analyzed using methods including the in-situ observation, the theoretical analysis, at al. The results show that the thick and hard rock stratum in the middle layer of the multi seam caves in a hierarchical manner under the in- fluence of the ground pressure and rock weak plane. The thick key strata collapse position is in the mid- dle position according to a comprehensive judgment of combing the identifying key stratum method, drilling core and ground pressure. The upper thick key strata is formed by the ＂masonry beam＂ structure and the lower thick hard roof is formed by the ＂cantilever beam＂ structure. The upper ＂masonry beam＂structure weakens the ground pressure influence and the cantilever beam structure became the main source of hydraulic support. The most dangerous state of the support is the combination broken of the cantilever beam and the masonry beam during coal mining, which brings some difficulties for roof con- trol. Specially, thick key strata are broken in a holistic manner, and form a step voussoir beam structure. Response measures should be taken in advance_
作者
冯军发
周英
张开智
徐佑林
李回贵
FENG Junfa1, ZHOU Ying1, ZHANG Kaizhi1, XU Youlin1, LI Huigui1(1. Institute of Mining Engineering, Guizhou Institute of Technology, Guiyang, Guizhou 550003, China 2. School ofEnergyScienceandEngineering, HenanPolytechnieUniversity, Jiaozuo, Henan 454000, Chin)
出处
《采矿与安全工程学报》
EI
CSCD
北大核心
2018年第2期332-338,共7页
Journal of Mining & Safety Engineering
基金
国家自然科学基金煤炭联合基金重点项目(U1261207)
国家自然科学基金项目(51564004)
贵州省教育厅创新群体重大研究项目(黔教合KY字[2016]042)
关键词
浅埋
厚关键层
砌体梁
悬臂梁
台阶岩梁
支架工作阻力
shallow seam
thick and hard roof
masonry beam
cantilever beam
step voussoir beam
shield working resistance
