【作者】 李晋平；

【导师】 姚建国； 宁宇； 康立军；

【作者基本信息】 煤炭科学研究总院 ， 采矿工程， 2005， 博士

【摘要】 随着采深加大、工作面单产的提高及地质条件的变化,潞安矿区综放工作面瓦斯超限频繁,严重制约了综放集约化生产水平进一步提高。根据对瓦斯治理途径的调研,创造性地提出在综放工作面采用大、小断面沿空留巷技术改变风流方向,从根本上治理瓦斯超限,从而实现特殊煤层条件下集约高效生产的技术思路。本文结合潞安矿区煤层开采条件,采用理论分析、实验室相似模拟、三维动态数值模拟和现场试验等综合研究手段和方法,对综放沿空留巷岩层控制理论、围岩稳定性、巷道支护技术及其矿压显现规律进行开拓性的系统研究,为沿空留巷在综放工作面的应用奠定基础。首次采用三维动态数值模拟的方法并结合相似材料模拟试验,分析了不同条件下沿空留巷围岩的稳定性及破坏特点,提出了综放沿空留巷巷内加强支护及巷旁支护的原则。根据对综放工作面锚网、锚索支护巷道垮落特征和老顶破断基本规律的分析,首次提出了综放沿空留巷围岩大、小结构的概念。通过对大结构关键块稳定性分析,论证了综放沿空留巷的可行性。通过对大、小断面沿空留巷矿压显现规律的现场实测研究,综放沿空留巷顶板活动与顶煤的破坏及放出密切相关,根据潞安常村煤矿、王庄煤矿沿空留巷矿压观测结果,巷道顶板下沉主要集中于工作面前方2m至工作面后方20m范围内,工作面后方20-40m后趋于稳定。常村煤矿综放大断面沿空留巷及王庄煤矿综放小断面沿空留巷工程实践证明应用综放沿空留巷技术实施“Y”型、“J”型通风可从根本上解决高瓦斯综放工作面瓦斯超限问题。通过理论分析、实验研究和现场试验,本文率先在国内初步建立了由大断面、小断面沿空留巷组成的综放沿空留巷技术体系。按照作者提出的效益支护原则,创造性地利用锚网支护巷道垮落后形成的免(减)压区实施小断面沿空留巷,通过高强度预应力锚索、全锚高强度锚杆锚网支护及高水材料充填支护提高顶煤、顶板及煤帮自身支承能力,首次成功地实现了综放工作面大断面沿空留巷。综放沿空留巷技术研究成果的成功应用为综放工作面实现集约化高效生产开拓了新路。更多还原

【Abstract】 As increasing of mining depth, advancing of outputs of a single working face and changing of geological conditions, the disallowed gas concentration appears frequently at longwall top coal caving face in Lu’an mining district, blocks the farther advancing of producing level. Based on the investigation about the approaches of gas control, this paper puts forward gob-side entry retaining technology with large and small section to change dissolute direction at longwall top coal caving face, prevent appearance of disallowed gas concentration radically, and realize intensive and high efficiency mining under the conditions of special coal seam. According to the mining conditions in Lu’an mining district, this paper study the rock strata controlling theory, stability of surrounding rock, roadway supporting technology and rules of phenomenon of underground pressure on gob-side entry retaining at longwall top coal caving face by compensative ways of theory analysis, similar simulation and 3-demension dynamic numerical simulation. This paper has setup the base for application of technology of gob-side entry retaining at longwall top coal caving face.This paper analyzed stability of surrounding rock influenced by gob-side entry retaining under different conditions and brings forward supporting inner and gob-side rules of entry by using 3-demension dynamic numerical simulation and similar simulation. According to analysis of collapse characters of roadway supporting by bolting and meshing or cable anchor and basic break rules of main roof ,this paper put forward the conception of large and small structure under the condition of gob-side entry retaining at longwall top coal caving face. Based on the stability analysis of key-block with large structure, the feasibility of gob-side entry retaining has been demonstrated. Through practical tests about rules of phenomenon of underground pressure influenced by gob-side entry retaining with large and small section, the relations of roof movements with top-coal broken and dropped are found: the convergence of roof appears mostly between 2 meters ahead of the working face and 15 or 20 meters behind the working face, and become to stability from 20 to 40 meters behind working face. Practices of gob-side entry retaining with large section at Changcun coal and with small section at Wangzhuang coal show that application of gob-side entry retaining with Y or J ventilation system can solve the problem of disallowedgas concentrations at high gassy longwall top coal caving face .With theory analysis, experiment research and spot test, this paper takes the lead in establishing technology system of gob-side entry retaining with large section or small one. According to rules of timbering economically, creatively utilized forming trigon "dismissing stress" or "low stress" zone in caved bolting and meshing entry, gob-side entry with small section is retained. Through pre-tensioned cable anchor with high strength, bolting and meshing support with high strength and filling with high-water material to increase supporting ability of top-coal, roof and coal wall, gob-side entry with large section is retained at longwall top coal caving face. Based on the successful application of gob-side entry retaining at longwall top coal caving face, a new way for realizing intensive and high efficiency is put forward in thick seams.更多还原