受载复合煤岩破裂表面红外辐射温度变化规律

Variation routine of surface infrared radiation temperature of composite coal rock in fracture under load

为实现对煤岩动力灾害的非接触式预测预报,采用红外热成像仪,研究由煤和顶底板岩组成的复合煤岩与泥岩受载变形直至破裂过程中表面红外辐射温度的演化特征。建立煤、顶底板岩、泥岩温度与应力、应变之间的拟合方程。研究结果表明,复合煤岩和泥岩试样加载产生红外辐射的物理机制一致,均存在热弹效应和摩擦热效应。煤岩破裂失稳红外辐射前兆表现为阶跃式、台阶式上升趋势;加载速率增大,温度变化更加明显,与应力、应变成较强线性正相关关系,其中,煤样红外辐射温度变化最大,顶底板岩的红外辐射温度变化相对较小;泥岩红外辐射温度有阶跃式、突增型上升趋势,温度变化较煤岩明显,其与应力、应变的相关性稍高于煤样和顶底板岩。

In order to realize the non-contactprediction of the coalrock dynamic disaster by infrared radiation and ensure coal mine safety,the evolution characteristics of surface infrared radiation temperature of composite coal rock and mudstonesample during deformation and fracturing were studied by infrared thermal imager. Fitting equation between temperature,stress and strain of coal,roofslab,floorslab and mudstone were established. The results show that there are thermoelastictand frictional hea effects during continuous loading tests of both samples.The physical mechanism is the same. Infrared radiation precursor of composite coal rock in fracture instability has been manifested as a rise in step. When the loading rate increasing,the temperature increases also.The temperature changes and stress or strain have a strong positive linear correlation. Infrared radiation temperature precursor of mudstone has been manifested as a trend of step and type spurt upward. The temperature change is more obvious than the coal rock. The correlation is slightly higher than the composite coal rock.