摘要
利用空芯包体地应力测量方法对分布于我国东北、华北、华中和华南的阜新、平顶山、鹤壁和淮南等7个煤与瓦斯突出矿区的地应力进行了测量。对测量结果的分析表明,煤与瓦斯突出矿区的地应力场作用特征表现为以下几点:(1)最大、最小主应力为水平主应力,中间主应力为垂直主应力,即应力场类型全部为大地动力场;(2)突出矿区的水平主应力远高于其他区域,突出矿区煤(岩)体承受更高的构造应力;(3)最大主应力与最小主应力的比值分布在1.56～3.93之间,其中69%分布在1.7～2.8之间,50%的测点最大主应力为最小主应力的2倍,最大主应力与最小主应力相差很大;(4)最大主应力与垂直应力比值随深度增加而减小,地应力场有从大地动力场向准静力场过渡的趋势。最后探讨了地应力在煤与瓦斯突出中的作用,分析认为在影响煤与瓦斯突出的地应力、瓦斯和煤体强度3个主要因素中,高地应力环境使瓦斯压力和瓦斯含量增加从而增加了突出的动力,使煤体破坏强度(峰值强度)降低从而减少了突出的阻力,总体上高地应力环境下含瓦斯煤体更容易出现失稳破坏、发生煤与瓦斯突出。煤与瓦斯突出矿区所具有的地应力场特征对突出的发生、发展具有重要的作用,是产生煤与瓦斯突出的核心因素。
The hollow inclusion technique is used to measure the in-situ stress of coal and gas outburst mining area The measurement sites lie in the Northeast, Middle and East China, which include 7 mining areas such as Fuxin, Pingdingshan, Hebi, and Huainan. Based on the analysis of measurement data from outburst mining areas, conclusions could be drawn as follow： （1） major principal stress and minor principal stress are horizontal stresses and the inter medium principal stress is vertical stress, and the type of stress field is the dynamic stress field; （2） the major principal stress and minor principal stress are higher than those of other regions; and the tectonic stress is outstanding： （3） the ratio of major principal to minor principal stress ranges from 1.56 to 3.93, in which 69% ranges from 1.7 to 2.8 and 50% is about 2.0; the subtract of major principal stress and minor principal stress is very salience; （4） the ratio of the major principal to the vertical stress decreases with the increase of depth. The stress field has the changing tendancy from dynamic to static. At last, the role of in-situ stress is discussed. The gas and coal strength are the main factors influencing coal and gas outburst. Gas pressure and gas content increase in hign in-situ stress environment, so the impetus of coal and gas outburst increase. Because the coal strength（peak strength） decreases, so the resistance of coal and gas outburst decreases. As a whole, in high in-situ stress environment, the gassy coal tends to be instable and coal gas outburst occurrs as a result. In-situ stress plays a key role during the occurring and development of coal and gas outburst. The characteristic, of in-situ stress fields have an important function in coal and gas outburst.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2008年第A02期3852-3859,共8页
Chinese Journal of Rock Mechanics and Engineering
基金
国家重点基础研究发展规划(973)项目(2005CB221501)
国家自然科学基金资助项目(50574047)
教育部高校博士点基金资助项目(20040147005)
关键词
岩石力学
煤与瓦斯突出
地应力场
地应力测量
rock mechanics
coal and gas outburst
in-situ stress field
in-situ stress measurement
