近距离煤层重复采动下深部采场稳定性分析  

Stability Analysis of Deep Stope under Repeated Mining in Close Distance Coal Seam

作　　者：王玉成 吴桂义[1] 孔德中[1] 周礼杰 WANG Yucheng;WU Guiyi;KONG Dezhong;ZHOU Lijie(School of Mining,Guizhou University,Guiyang 550025,China)

机构地区：[1]贵州大学矿业学院,贵阳550025

出　　处：《煤炭技术》2023年第8期32-36,共5页Coal Technology

基　　金：国家自然科学基金地区科学基金项目(52164002,52164005);贵州省科技计划项目(黔科合支撑[2021]一般399)。

摘　　要：针对近距离煤层重复采动下深部采场失稳这一难题,采用理论分析、相似模拟与数值模拟相结合的方法,研究了重复采动下深部采场稳定性。研究得到:在深部高地应力场、高地温场和重复开采扰动的三者共同作用影响下,采场硬岩会表现出流变特征,软岩破坏也会出现较大的塑性变形,导致岩体强度变得更低,在相同顶板压力作用下采场更容易失稳;5#煤层开采时,采场上方顶板将形成“拱式”结构和“砌体梁”结构,并会出现2种不同程度的顶板来压现象,频繁来压易造成采场顶板冒顶与煤壁片帮,导致采场失稳;在近距离煤层重复采动下,下位煤层采场围岩稳定性遭到破坏,下工作面周期来压呈不规律现象,失稳的主控因素是采场顶板厚度与煤层厚度比和顶板岩体强度,在深部开采复杂条件下保障采场稳定性的措施是对顶板与煤壁进行超前加固。Aiming at the problem of deep stope instability caused by repeated mining of close coal seams,theoretical analysis,similarity simulation and numerical simulation were used to study the stability of deep stope under repeated mining.The results show that under the combined influence of deep high ground stress field,high ground temperature field and repeated mining disturbance,the hard rock in stope will show rheological characteristics,and the soft rock will also have large plastic deformation when it is destroyed,resulting in lower rock strength and easier instability of stope under the same roof pressure.When No.5 coal seam is mined,the roof above the stope will form an"arch"structure and a"masonry beam"structure,and there will be two roof weighting phenomena in different degrees.Frequent weighting will easily cause roof caving and coal wall spalling in the stope,resulting in stope instability.Under the repeated mining of close coal seam,the stability of surrounding rock in lower coal seam stope is destroyed,and the periodic weighting of lower working face is irregular.The main factors of instability are the ratio of roof thickness to coal seam thickness and the strength of roof rock mass.The measure to ensure the stability of stope under complex conditions of deep mining is to reinforce the roof and coal wall in advance.

关 键 词：近距离煤层 深部开采 重复采动 采场稳定性 相似模拟 

分 类 号：TD322[矿业工程—矿井建设] TD325