不同荷载作用下煤岩裂隙扩展研究

我国是煤炭生产与使用大国,煤岩也是岩土工程中一种常见材料.研究岩石在受荷载作用下裂隙发展过程是解决岩石破坏机制的中心任务.本文介绍了如何利用扫描电镜对单轴以及三轴压缩后的煤岩试样进行观测,获得了煤岩破坏细观结构的照片.再基于Matlab的数学统计工具箱和区域生长算法,编制图像处理程序,得到煤岩破坏时裂隙的方位角、宽度、长度等信息.利用正态分布,对裂隙的方位角、长度进行统计分析,得到其期望与方差的无偏估计量.最后基于Monte Carlo理论,对煤岩破坏细观损伤过程进行模拟,并与试验数据进行对比,找出单轴与三轴压缩试验下煤岩破坏形式的区别.

Study of Crack Extension of Coal under Different Loadings

At present China is leading the list of world＇s largest producers and users of coal, due to which the use of coal petrography method is a vital ingredient in today＇s geotechnical engineering field. The area of study relating to the extension of cracks in rocks, under loading is a key to understand its deformation and failure mechanism. This paper presents how to observe the uniaxial and triaxial compression tests, by implementing the methodology of scanning through electron microscopy. That would assist to obtain the photos of coal petrography post-failure mechanisms. And the paper also draws it focus towards measuring the data of micro- cracks＇ azimuth angle, length, and width based on the correlation functions in the MATLAB. And then it describes the implementation of the statistical method to get the expectation and variance of microcracks＂ azimuth angle, length, and width. Finally, by using the Monte Carlo theory to simulate and comparing with the experimental data, the differences between the failure modes of uniaxial and triaxial compression tests are found.