大倾角煤层长壁大采高采场煤壁片帮机制  

Coal wall caving mechanism of longwall large mining height stope in steeply dipping coal seams

作　　者：张浩[1] 伍永平[1] ZHANG Hao;WU Yongping(School of Mineral Engineering, Xi'an University of Science and Technology, Key Laboratory of Western Mine Exploitationand Hazard Prevention Ministry of Education, Xi'an, Shaanxi 710054, China)

机构地区：[1]西安科技大学能源学院西部矿井开采及灾害防治教育部重点实验室,陕西西安710054

出　　处：《采矿与安全工程学报》2019年第2期331-337,共7页Journal of Mining & Safety Engineering

基　　金：国家自然科学基金重点项目(51634007)

摘　　要：煤壁片帮是大采高采场普遍性开采技术难题,而大倾角条件下大采高采场煤壁片帮特征及其发生机理更为复杂,为弄清该类采场煤壁片帮机制,采用现场实测、数值计算及理论分析法,对大倾角煤层大采高采场煤壁片帮特征、影响因素、片帮机制进行研究。结果表明:大倾角大采高采场煤壁片帮具有交替演变,不同区域形式不同,片滑、回转外片等特征;采高、伪斜角、煤体力学特性与煤壁稳定性密切相关,采高、伪斜角一定范围内越大,煤体强度越低,煤壁片帮几率及程度随之增加,而25221工作面煤壁强度低、含夹矸、高度大,自稳性差,采高及伪斜角大且不断变化,导致顶压作用强度增加,加之重复性动态荷载扰动,复合因素叠加作用促使大倾角大采高采场煤壁发生片帮。Coal wall caving is a common mining technical problem for large mining height stope, and the caving feature and its occurrence mechanism are more complicated under steeply dipping condition.Through field measurement, numerical calculation and theory analysis, the caving features, influencing factors and the caving mechanism have been studied. The results have shown that coal wall caving of large mining height stope in steeply dipping coal seams has distinctive features, such as alternating evolution, different regional forms and so on. It also reveals that mining height, pseudo angle, mechanical properties of coal are all closely related to coal wall stability-within a certain range: the bigger mining height and pseudo angle, the lower the coal strength becomes, and the more probability and extent of coal wall caving accordingly increase. Working face 25221, with low strength coal walls, gangue, a large height, poor self-stability, and variable mining height and pseudo-angle, increases the roof pressure strength, coupled with the repetitive dynamic load disturbance and other internal and external factors, promotes the coal wall caving of large mining height stope in steeply dipping coal seams.

关 键 词：大倾角 大采高 片帮特征 滑帮 片帮机制 

分 类 号：TD323[矿业工程—矿井建设]