煤与瓦斯突出渗透失稳机理研究

项目名称： 煤与瓦斯突出渗透失稳机理研究

项目编号： No.41272171

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 天文学、地球科学

项目作者： 谢焰

作者单位： 安徽理工大学

项目金额： 84万元

中文摘要： 按《防治煤与瓦斯突出规定》，"破坏类型为Ⅲ、Ⅳ、Ⅴ类的煤层"是判定煤层是否会发生突出的单项指标之一。此类煤体为粒状、土状，手捻即碎，硬度低，煤地质学称这类煤体为"构造煤"，申请人按照岩体结构分类，将之划归为散体状结构岩体。在岩土工程中，具有散体状结构的岩体通常按土体处理。在分析地面煤田钻井抑突效应和蒋承林巷道增压抑突试验成果的基础上，借鉴土力学流土理论，申请人提出煤与瓦斯突出属渗透失稳的观点。把突出分为在地应力作用下的煤体破碎及瓦斯压力梯度的调整、在渗透压力作用下的煤体失稳和在膨胀能作用下的煤粉搬运3个阶段，认为"构造煤"是渗透失稳的物性基础，渗透失稳是"构造煤"发生失稳的具体模式，煤体抗失稳强度用临界失稳梯度表示。本项目拟研究：①通过试验检验煤层是否存在临界失稳梯度；②通过试验检验加快煤层瓦斯压力梯度下降速率能否降低突出强度；③研究临界失稳梯度的影响因素，建立煤层渗透失稳的数学物理模型。

中文关键词： 渗透失稳；判别式；数学模型；反滤层；煤与瓦斯突出

英文摘要： According to the standards for classification of rock mass structure, damage degree Ⅲ,Ⅳ and Ⅴ coal seams in "coal and gas outburst prevention provisions",which are called "tectonic coal" in coal geology,were regarded as loose structure rock mass,which are treated as soil in geotechnical engineering.Based on the soil flow theory of soil mechanics,an analysis was conducted on the surface coalfield drilling,the pressurized test of the gateway in lab. A view was provided that the coal gas outburst be the permeability stability lost．An outburst could be divided into three stages．The first stage would be a stage in which coal seams were crashed and gas pressure gradient fields were adjusted by crustal stress. The second stage would be a seam lost stability stage by gas permeation pressure induced by gas pressure gradient.The third stage would be the coal particles migrating stage by the gas expansion power. The gas pressure gradient of the seam would be cinsidered as a strength index that prevents the outburst occuring. The following works would be done: Firstly, a test woud be made to verify whether there be a critical gas pressure gradient when outburst occures. Secondly, another test would be made to determine the relationship between the rate of gas pressure gradient decreasing and the outburst magnitude.Thi

英文关键词： seepage instability；discriminate equation；mathematical model；anti-filter layer；outburst of coal and gas