大倾角近距离煤层群长壁采场顶板破断机理  

Roof breaking mechanism of longwall stope with steeply dipping contugous coal seam group

作　　者：解盘石[1,2] 屈利利 伍永平[1,2] 张颖异 闫壮壮 冯坤 杨广兵 吉峰 XIE Panshi;QU Lili;WU Yongping;ZHANG Yingyi;YAN Zhuangzhuang;FENG Kun;YANG Guangbing;JI Feng(Key Laboratory of Western Mine Exploitation and Hazard Prevention Ministry of Education,Xi’an University of Science and Technology,Xi’an 710054,China;College of Energy Science and Engineering,Xi’an University of Science and Technology,Xi’an 710054,China;Shandong Mining Machinery Huaneng Equipment Manufacturing Co.,Ltd.,Weifang 261000,China)

机构地区：[1]西安科技大学西部矿井开采及灾害防治教育部重点实验室,陕西西安710054 [2]西安科技大学能源学院,陕西西安710054 [3]山东矿机华能装备制造有限公司,山东潍坊261000

出　　处：《煤炭科学技术》2022年第2期65-74,共10页Coal Science and Technology

基　　金：国家自然科学基金面上资助项目(52174126)。

摘　　要：大倾角近距离煤层群开采时,下层煤采场顶板受到重复加-卸载作用,其覆岩运移和矸石充填特征较单一煤层开采时更为复杂。以东峡煤矿大倾角近距离煤层群为研究对象,采用物理相似材料模拟试验、理论分析和现场实测相结合的手段,通过建立基于下层煤采场顶板的两端固支梁模型,确定了采场顶板易发生弯曲破断的位置,研究了大倾角近距离煤层群长壁采场顶板破断垮落特征。结果表明,上层煤采空区垮落顶板的堆积沿倾向具有不均衡性;垮落顶板与顶板残垣轮廓的接触程度存在差异性,沿垂直岩层方向可将垮落覆岩划分为完整倾斜砌体区域与倾斜砌体缺失区域。上层煤工作面底板受载沿倾向表现为分区特征,根据采空区的非对称充填特征将其划分为受近似点载荷的无矸石充填区和受非均衡作用的中、下部矸石充填区。下层煤开采时,采场倾斜中上部顶板(顶煤)先破坏下滑、充填至下部采空区,致使下部区域工作面顶板弯矩较小、倾斜中上部顶板弯矩较大,其中倾斜中上部顶板更易发生破断。由于采空区充填程度不同,下层煤采场来压呈现中部较大、上部次之、下部无明显来压的基本特征。相对于单一煤层开采,下煤层开采时周期性来压的强度较低且规律性不强。研究可为大倾角煤层群长壁采场顶板稳定性控制提供一定的理论支撑。The roof of the lower coal stope is subjected to repeated loading and unloading during the mining of steeply dipping contugous coal seam group.The characteristics of overlying rock migration and gangue filling are more complicated than those of a single coal seam.Taking the steeply dipping contugous coal seam group of Dongxia Coal Mine as the research object,physical similar material simulation ex⁃periment,theoretical analysis and field measurement were combined.The roof’s location was prone to bending and breaking is determined by establishing a fixed beam model based on the bottom coal stope roof.They were used to study the roof failure characteristics.The results show that the accumulation of caving roof in upper coal goaf is unbalanced along the inclination.There are differences in the contact degree between the collapsed and residual roof.The caved overlying rock can be divided into complete incline masonry areas and missing prone masonry areas along the vertical rock layer.The bottom load of the upper coal face presents zoning characteristics along the dip,according to the asymmetric filling characteristics of caving roof,it can be divided into gangue free filling area subject to approximate point load and middle and lower gangue filling area subject to disequilibrium.When the lower coal is mined,the inclined upper roof of the stope dama⁃ges,slides down and fills the lower goaf.This leads to smaller bending moment of the lower stope roof and larger bending moment of the inclined middle and upper roof,in which the inclined middle and upper roof is more likely to break.Due to the different filling degree of goaf,the roof weighting of lower coal stope is larger in the middle part,followed by the upper part and smallest in the lower part.Com⁃pared with single coal seam mining,the intensity of periodic pressure in lower coal seam mining is low and the regularity is inconspicu⁃ous.The research can provide theoretical support for the roof stability control of longwall stope of steeply dipping contugous c

关 键 词：大倾角煤层群 长壁开采 不均衡充填 复杂力系 顶板稳定性控制 

分 类 号：TD315[矿业工程—矿井建设]