气煤热力耦合变形与孔隙演化特征的实验研究  

Experimental study on coupled thermo-mechanical deformation and pore evolution feature of gas coal

作　　者：周长冰[1] 万志军[1] 张源[1] 国峰 朱成坦[1] 刘建明[1] 程才[1] 

机构地区：[1]中国矿业大学矿业工程学院深部煤炭资源开采教育部重点实验室,江苏徐州221116 [2]金建工程设计有限公司,山东烟台264070

出　　处：《中南大学学报（自然科学版）》2014年第7期2440-2446,共7页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(51074164);教育部新世纪优秀人才支持计划项目(NCET-10-0770);江苏省“333工程”资助项目(BRA2010133)

摘　　要：采用自主研制的"600℃20 MN伺服控制高温高压岩体三轴试验机",进行直径×高度为200 mm×400 mm的山东兴隆庄气煤试样高温三轴应力下的耦合热变形实验,对实验后的煤样采样,与非实验煤样进行对照压汞实验及孔隙结构分析。研究结果表明:三轴恒定应力下,气煤随温度升高的热变形可分为3个阶段:缓慢变形阶段、快速变形阶段和破坏阶段;试样由缓慢变形阶段进入快速变形阶段、渗透率激变以及脆韧转化三者具有相同的阀值,都是因气煤热解产生孔隙所致;三轴应力下气煤随温度升高的热变形特征和渗透性变化规律均由大孔的发育程度决定,且试样压缩的空间取决于大孔的体积。Adopting the “600 ℃ 20 MN servo-controlled high temperature and high pressure rock triaxial testing machine” which is developed independently by CUMT, the coupled thermal deformation experiments with Φ200 mm× 400 mm gas coal sample of Shandong Xinglongzhuang at high temperature and triaxial stress were made. Contrast mercury intrusion experiments were made between pressed samples and non-pressed samples, and the pore structure was analyzed. The results indicate that the heat deformation of gas coal with the rising temperature under the triaxial constant stress can be divided into three stages, i.e. the slow deformation stage, the rapid deformation stage and the destruction stage. The deformation of stage is from slow to rapid, permeability drastically changes and brittle-ductile transformation has the same threshold value. All of these phenomena are caused by the pore which is generated by gas coal pyrolysis. The thermal deformation characteristics and permeability variation rule of gas coal with the increase of temperature under triaxial stress are both decided by the development degree of the large hole, and the space of compression depends on the volume of large holes.

关 键 词：热力耦合 气煤 变形 孔隙 

分 类 号：TD315[矿业工程—矿井建设]