钢混凝土界面接触热阻试验研究
Experimental analysis of interface thermal contact resistance between steel and concrete

火灾条件下钢管与混凝土间界面热阻对结构温度场有很大影响。利用INSTRON 8874型高温材料试验机的高温接触热阻试验装置对钢-混凝土界面接触热阻进行了试验研究，根据各测点的温度时间历程曲线，利用多项式拟和方法外推得到钢、混凝土界面处温度值，通过热传导方程和接触热阻定义得到了界面接触热阻。试验结果表明，不同界面压力下钢管混凝土界面的接触热阻数值比较稳定，与文献结果相比有一定可靠性；界面压力下钢管混凝土界面的接触热阻数值离散性大，随温度变化明显。
Under Fire conditions， the interface thermal resistance between steel and concrete has important influence on structure temperature field. TheINSTRON 8874 material testing machine for high temperature thermal contact resistance testing device was used to conduct the thermal contact resistance experiments of steel and concrete interface. According to the time history curve of each measuring point's temperature，the interface temperature near steel and near concrete was obtained using the polynomial fitting and extrapolation method. The interface thermal contact resistance was calculated by heat conduction equation and definition of thermal contact resistance. The test results showed that under different interface pressure，the thermal contact resistance value was constant and comparatively consistent with the literature; Without interface pressure，the thermal contact resistance value was unstable and varied obviously with temperature.