大倾角煤层长壁开采空间应力拱壳形态研究  

Study on the shape of the space stress arch shell in steeply dipping coal seam mining

作　　者：罗生虎[1,2] 伍永平[2,3] 刘孔智 解盘石[2,3] 郎丁[2,3] 

机构地区：[1]西安科技大学理学院,陕西西安710054 [2]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 [3]西安科技大学能源学院,陕西西安710054 [4]重庆能源(贵州)煤电有限公司,贵州毕节551700

出　　处：《煤炭学报》2016年第12期2993-2998,共6页Journal of China Coal Society

基　　金：国家自然科学基金重点资助项目(51634007);国家自然科学基金资助项目(51204132);陕西省青年科技新星支持计划资助项目(2015kjxx-36)

摘　　要：大倾角煤层特殊的赋存条件,造成在大倾角煤层开采中顶板空间应力场的演化规律、顶板破断垮落后所形成的围岩结构等较缓倾斜煤层开采时异常复杂,导致维持顶板稳定性的难道加大。基于大倾角煤层开采物理相似材料模拟实验和数值仿真结果,分析了在大倾角煤层开采中围岩结构的基本特征和应力拱壳的基本特性,认为非对称空间应力拱壳是开采扰动破坏原岩应力平衡后,上覆岩层在自我组织能力作用下所形成的主应力迹线的空间展布形态,空间应力拱壳沿走向对称,沿倾向非对称,且当工作面推进距离远大于工作面长度时,空间应力拱壳中间区域沿倾向的形态基本保持不变。据此,在考虑冒落矸石非均匀充填效应的基础上,建立了沿倾向和沿走向的三铰拱力学模型,推导给出了沿倾向非对称拱和沿走向对称拱的轴线方程,并通过算例对研究结果进行验证。结果表明,文中给出的轴线方程能较好的描述采场空间应力拱壳的基本形态;当工作面推进距离远大于工作面长度时,空间应力拱壳沿走向两端对称区域的形态基本保持不变;沿走向对称应力拱的拱高和跨长在倾斜方向上呈先增大后减小的趋势;最大垮落高度在倾向方向的中上部区域,该区域走向应力拱的跨长和拱高也最大。The evolution law of the spatial stress field in roof, and the space form of surrounding rock structure after the coal seam mining in steeply dipping seam mining is unconventionally complex compared with the mining of gently-in- clined coal seam, which is due to the buried conditions of the steeply dipping seam. Based on the results of the physical simulation experiments and numerical simulation of steeply dipping seam mining, the basic mechanical characteris- tics of the space shape of arch shell after coal seam mining was analyzed. It revealed that the space shape of arch shell after coal seam mining, which is belong to mining disturbance, is an optimal structure. The shell structure is symmetric along coal seam strike but not along the inclination of coal seam. Accordingly, considering waste rock filling effect, the model of stress arch along coal seam strike and inclination of coal seam is established. The rational axis equation along coal seam strike and inclination of coal seam is obtained. The results show that when working face advancing distance is far greater than tile length of the working face, tile shell structure configuration is independent with the working face advancing distance. The arch height and span length of symmetric stress arch increase firstly and decrease later along the inclination of coal seam. The maximum caving height is in the middle and upper part of the inclination direction, and the arch height and span length of symmetric stress arch is the largest in that zone.

关 键 词：大倾角煤层 应力拱壳 形态方程 

分 类 号：TD823.21[矿业工程—煤矿开采]