【摘要】 钻掘过程中岩石的发热效应对岩石材料性能和热损伤会产生重要影响。介绍了红外热像仪的测温原理并利用红外热像仪对硬质灰岩钻掘过程的红外热像进行了试验研究。试验结果表明:钻掘过程中钻头前端岩石的热影响区呈类似弹头的形状,热影响区的厚度与钻头半径大致相当;钻掘结束后的冷却过程中热影响区温度总体降低,热影响范围逐渐扩大;钻孔轴线上岩石温度总体下降,最高点位置随时间发生变化,并有逐渐趋同的趋势,具体与钻孔直径、深度和岩石与空气的热物性质有关;热影响区内岩石温度最高值的下降速度表现为先快后慢,即钻掘刚结束时的温度下降速度最快,然后随时间推移温降速度逐渐放缓。试验结果证实了红外热像仪应用于岩石钻掘温度的动态测量与分析的有效性与实用性,研究结论为进一步改善钻掘效率和提高工程安全性提供了重要的参考依据。更多还原

【Abstract】 Thermal effects have significant impacts to material properties and thermal injury of the rock during rock excavation.The measurement principle of infrared imaging temperature is introduced.Infrared-Charge Coupled Device(IR-CCD) was used to study the infrared thermal image of the rock during excavation process.The experimental results under certain conditions show that thermal-affected zone of the rock in drilling was similar to the shape of warhead,and the thickness of thermal-affected zone was roughly the same as radius of the drill bit.The average temperature of the thermal-affected zone reduces during the cooling process after drilling,but the area of the thermal-affected zone expands gradually.The rock temperature in drilling axes reduces and the position of the max temperature point on it is changing with the cooling time,the discrepancy between each other is also decreasing as time pass by.This process is influenced by drilling diameter,drilling depth,the thermal and mechanical properties etc.The decreasing speed of maximum temperature in the rock is faster in the beginning of the cooling process than it in the middle and the end of the process.Experimental results confirm that it is utility and effective to use IR-CCD in measuring and analysing the rock temperature in drilling.The conclusions provide important references to improve the efficiency and security of the drilling project.更多还原