煤矸石的强度特征试验研究

EXPERIMENTAL STUDY ON STRENGTH PROPERTIES OF COAL WASTES

通过中型三轴试验及现场大型直剪试验对煤矸石的强度特性进行了系统研究,得到了煤矸石强度包线的形式和参数以及煤矸石抗剪强度随粗颗粒(粒径D>5.0mm)含量的变化规律,并对试验中最大主应力差及颗粒破碎量进行多元统计分析,得到围压、孔隙比及粗料含量的变化规律。

Based on the medium-sized triaxial test and the large-scale field direct shear test, the strength properties of coal wastes from Xuzhou in China, are systematically studied. The results show that the strength of coal wastes can be described by Coulomb＇s equation or De Mello equation for shear strength. The parameters for these formula are presented. When the coarse grain（D〉5.0 mm） proportion in samples changes from 30% to 60%, the shear strength is seen with obvious changes differently with the pure coarse or fine samples. The influential factors on the coarse crush are also compared, in which the confining pressure and the coarse grain content are the primary factors. In the end of the paper, it is indicated that the cohesion of coal waste from the field shear test is smaller than that from laboratory test; while the friction angle from the field test is larger than that from the laboratory test. The mechanism for above results is achieved.