含瓦斯煤单轴压缩的尺度效应实验研究  

Experimental Study of Scale Effect on Gas-saturated Coal Samples subjected to Uniaxial Compression

作　　者：宋良[1] 刘卫群[1] 靳翠军[1] 李玉寿[1] 

机构地区：[1]中国矿业大学理学院深部岩土力学与地下工程国家重点实验室,江苏徐州221008

出　　处：《实验力学》2009年第2期127-132,共6页Journal of Experimental Mechanics

基　　金：国家自然科学基金项目(50774083;40811120546);教育部"新世纪优秀人才支持计划"课题(NCET-07-0803);国家"973计划"项目子课题(2005CB221502)

摘　　要：含瓦斯煤与其它岩石类材料一样,在力学特性等方面具有尺度效应。利用特制的饱和加压装置和电子万能试验机,对不同尺度、不同饱和瓦斯压力下的煤样进行了单轴压缩试验,探讨了煤样变形破坏及强度特性的变化规律。分析表明,煤样抗压强度、弹性模量随瓦斯压力的增大而减小,抗压强度随高径比的增加明显减小,弹性模量随高径比的增加略有提高。利用Weibull模型和线弹性强化理论对含瓦斯煤产生尺度效应的原因进行了合理地解释,为含瓦斯煤样尺度效应在强度表征等方面的深入研究提供了新的实验和理论依据。Like many other rock materials, the mechanical properties of gas-saturated coal also present scale effect. Home-made coal saturation and compression apparatus were used together with an electronic universal testing machine to conduct uniaxial compression of gas-saturated coal samples with different gas pressures and different height-diameter ratios. Before compression, coal samples were saturated by methane gas with different pressures. Sample deformation and fracture, pressure strength and Young＇s modulus relative to scale effect of gas-saturated coal were analysed. Results show that both ultimate compression strength and Young＇s modulus decrease along with the gas pressure growing and the height-diameter ratio increasing, but Young＇s modulus decreasing is not so distinct as the compression strength. Young＇s modulus increases slightly along with the height- diameter ratio increasing. Scale effect revealed in this paper can be explained reasonably by Weibull model and enhanced line-flexible model. The results may provide new experimental and theoretical approaches to further investigating scale effect of rock materials.

关 键 词：单轴压缩 含瓦斯煤 瓦斯压力 尺度效应 

分 类 号：TD315.1[矿业工程—矿井建设]