深部矿井围岩导热系数热变特性试验研究

Experimental Study on Thermal Variation Characteristics of Surrounding Rock Thermal Conductivity Coefficient in Deep Mines

围岩放热是深部矿井热环境恶化的诱因之一,而围岩的导热系数是描述围岩热传输能力的关键参数。在对招远某金矿岩样的试验研究中,通过激光导热仪对花岗岩试样在25℃至200℃之间的导热系数进行了测量,并利用扫描电镜进一步分析了花岗岩试样随着温度变化的微观损伤状况。试验结果表明,当温度升高时,花岗岩试样的导热系数会降低,温度从25℃升到200℃时,花岗岩试样的平均导热系数从3.658 W/(m·K)下降至2.811 W/(m·K),研究结果为井下热害防治提供了试验基础。

The heat release of surrounding rock is one of the deterioration inducement of the deep mine thermal environment. Thermal conductivity coefficient is a key parameter to describe the heat transfer ability of surrounding rock. In the experimental research on rock samples of a gold mine in Zhaoyuan, the thermal conductivity coefficient of the granite samples between 25℃and 200℃ was measured by the laser thermal conductivity meter and the scanning electron microscope was used to further analyze the microscopic damage condition of the granite samples with the temperature change. The experimental results show that the thermal conductivity of the granite sample will decrease when the temperature rises. When the temperature rises from 25℃ to 200℃, the average thermal conductivity coefficient of the granite sample drops from 3.658 W/(m·K) to 2.811 W/(m·K). The research results provide an experimental basis for the prevention and control of thermal hazards.