大倾角煤层长壁开采空间应力拱壳形态研究

发布时间：2018-03-24 22:08

本文选题：大倾角煤层　切入点：应力拱壳　出处：《煤炭学报》2016年12期

【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。
[Abstract]:Because of the special occurrence conditions of large dip coal seam, the evolution law of roof space stress field in large dip coal seam mining is caused, and the surrounding rock structure formed by roof breaking and falling backward is more complicated than that in gently inclined coal seam mining. Based on the simulation experiments and numerical simulation results of physical similar materials in large dip coal seam mining, the basic characteristics of surrounding rock structure and stress arch shell in large dip coal seam mining are analyzed. It is considered that the asymmetric spatial stress arch shell is the spatial distribution form of the main stress trace line formed by the overlying strata under the action of self-organization ability after the mining disturbance destroys the stress balance of the original rock, and the spatial stress arch shell is symmetrical along the strike direction and tends to asymmetry along the direction. And when the working face advance distance is far longer than the working face length, the shape of spatial stress arch shell along the middle of the inclination is basically unchanged. Accordingly, considering the non-uniform filling effect of caving gangue, The mechanical model of three-hinged arch along inclination and strike is established. The axial equations of asymmetric arch and symmetrical arch along trend are derived, and the results are verified by numerical examples. The axis equation given in this paper can describe the basic shape of spatial stress arch shell in stope, when the distance of working face is far greater than the length of working face, the shape of symmetrical region along the direction of space stress arch shell remains basically unchanged. The arch height and span length increase first and then decrease in the inclined direction, and the maximum collapse height is in the middle and upper part of the inclined direction, the span length and the arch height of the stress arch in the strike direction are also the largest.
【作者单位】：西安科技大学理学院;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;西安科技大学能源学院;重庆能源(贵州)煤电有限公司;
【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)
【分类号】：TD823.21

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