摘要
高瓦斯煤层动力灾害是煤炭资源开采过程中常见的自然灾害,主要表现为瓦斯突出,对煤炭安全生产有巨大的威胁。以钱家营煤矿-850 m水平主石门掘进巷道为工程背景,通过现场探查、数值模拟等方法,分析了瓦斯突出诱发巷道冒顶灾害的机理。结果表明,巷道上方邻近煤层中高瓦斯压力及变异煤厚影响了冒落区周围的垂向应力分布,使应力突变并出现应力集中现象,进而诱发巷道顶板冒落。针对现场工程条件,试验了一种巷道超前锚注修复技术,此技术包括煤层瓦斯抽采、顶板冒落区注浆固化及锚杆支护三部分。现场采用此项技术后,瓦斯压力从4.60 MPa降到0.10 MPa,巷道安全通过了冒落危险区,两帮、顶底板最大变形量实测值分别为48 mm、4 mm,无明显变形破坏,满足生产要求。
This paper takes the horizontal main rock gate roadway at the depth of 850 m as an engineering background sample of Qianjiaying coal mine to solve the problem of roof-fall caused by the gas outburst.As is well known,high gas coal seam dynamic disaster belongs to an ordinary natural disaster in the process of the coal resource exploitation,which is mainly characterized by the gas outburst and in turn imposes a great threat to the coal safety production.Through a theoretical analysis,we can find that the root cause of the fall collapse belongs to the change in the stress of the roadway,for the gas pressure and variation of the coal thickness can influence the direct change of the factors involving the stress of the roadway and the coal seam.Therefore,it is of great impact of the 2 factors on the stress field of the roadway by the numerical simulation method,whose mechanism is necessary to be analyzed.And,then,it is also necessary to check and test the pre-advanced anchor repair technology for the roadway caving area based on the spot engineering conditions in combination with the on-site detection and simulation results.The technology items here involved may include the gas extraction,the grouting solidification in the roof falling area and the bolt support.And,what is more,the gas extraction of the 5 said coal species of the above roadway has to be tested and controlled so as to reduce the gas content rate in the coal seam,and then to formulate a new bearing structure of the grouting solidification and bolt support means to heighten the stability of the roadway surrounding rock or rocks by following the construction sequential order of the advanced anchor injection repair technolo-gy primarily.Thus,the research results can help us to reveal the following aspects:(1)The variation of the thickness of the coal seams may affect the stress distribution,and the stress concentration rate may experience some changes near the variation zone of the coal thickness,so as to promote the formulation and demonstration of the so-called"single peak"phenomenon.And,next,the above said phenomena of the gas pressure may further expand the unevenness of the stress distribution.The gas pressure model with 4 MPa should be equal twice as much as to that of the gas pressure-free model,which can then lead to the stress increase of the concentration range;(2)However,there still exists a weak rock stratum in the caving area,with the bearing capacity of the roof being weak.On that situation,when the gas outburst occurs in the 5 coal mines,the roof of the main stone gate road may go to a dangerous fall;(3)The gas pressure can be reduced from 4.60 MPa to 0.10 MPa,which has actually been reduced by a percentage of 98%.Therefore,the measured values of the maximum deformation of the 2 gangs and the top and bottom plate,without obvious deformation and damage,may come to 48 mm and 4 mm,respectively,which should be taken as in conforming to the production demands.
作者
刘凤文
蓝盛
张盛
LIU Feng-wen;LAN Sheng;ZHANG Sheng(Kailuan ( Group) Co.,Ltd.,Tangshan 063000,Hebei,China;College of Mining and Safety Engineering,Shandong University of Science and Technology,Qingdao 266590,Shandong,China)
出处
《安全与环境学报》
CAS
CSCD
北大核心
2019年第4期1154-1161,共8页
Journal of Safety and Environment
关键词
安全工程
突出煤层
煤厚变异区
超前锚注
冒落区修复
瓦斯治理
safety engineering
outburst coal seam
coal thickness variation zone
advanced anchor grouting
caving area repair
gas control
