Abstract

Soft coal is characterized by low strength and weak bonds, which play a key role in the occurrence and development of dynamic disasters. A more thorough understanding of the failure mechanics and infrared radiation characteristics of soft coal at various moisture contents is needed. In this study, infrared radiation experiments were conducted for soft coal at various moisture contents. The results indicate that moisture content affects compressive strength and elastic modulus of soft coal with compressive strength and elastic modulus being highest at moderate. Moisture has a substantial influence on the infrared radiation of compressed coal samples. Soft coals with high moisture contents show a smaller fluctuation of the average infrared radiation temperature curve and a stronger direct relationship of temperature and stress in the linear elastic stage. The coal samples with various moisture contents show a warming trend during loading. The increased amplitude of infrared radiation temperature per unit stress shows a linear relationship with moisture content. A large number of high temperature red spots appear along the diagonal line of coal samples with 0% moisture content before fracture, while changes in the infrared thermal image of the coal sample with 4% moisture content were negligible during loading.

摘要

软煤的特点是强度低，粘结力弱，这在动态灾害的发生和发展中起着关键作用。需要对软煤在各种含水量下的破坏机理和红外辐射特性有更透彻的了解。在这项研究中，对软煤在不同含水量下进行了红外辐射实验。结果表明，含水量影响软煤的抗压强度和弹性模量，其中抗压强度和弹性模量最高。水分对压缩煤样品的红外辐射有很大影响。水分含量高的软煤在线性弹性阶段平均红外辐射温度曲线波动较小，温度与应力的直接关系更强。各种水分含量的煤样品在装载过程中都呈现出变暖的趋势。每单位应力的红外辐射温度增加的幅度与水分含量呈线性关系。含水量为0％的煤样在断裂前的对角线上会出现大量的高温红点，而含水量为4％的煤样的红外热像变化在加载过程中可忽略不计。每单位应力的红外辐射温度增加的幅度与水分含量呈线性关系。含水量为0％的煤样在断裂前的对角线上会出现大量的高温红色斑点，而含水量为4％的煤样的红外热像变化在加载过程中可忽略不计。每单位应力的红外辐射温度增加的幅度与水分含量呈线性关系。含水量为0％的煤样在断裂前的对角线上会出现大量的高温红色斑点，而含水量为4％的煤样的红外热像变化在加载过程中可忽略不计。