钢管混凝土柱抗火性能研究

Study on fire-resistance performance of reinforced concrete filled steel tubular columns

对没有防火保护的钢管混凝土柱的抗火性能及其分析方法进行研究。通过没有防火保护的配筋钢管混凝土柱的火灾试验,研究了配筋钢管混凝土柱的火灾行为、截面温度场、变形和耐火极限,试验结果表明配筋可以显著提高钢管混凝土柱的耐火极限。探讨了配筋钢管混凝土柱抗火性能的数值模拟方法,在数值模拟中考虑了水分、接触热阻和高温瞬态热应变的影响,通过与试验结果的对比表明数值方法可以较好地计算柱的变形和耐火极限,并且能够满足工程应用的精度要求。最后在数值计算结果和试验结果的基础上,给出了配筋钢管混凝土柱截面温度场和耐火极限的简化计算方法,以方便实用。

The fire-resistance performance and analytical method of concrete filled steel tubular columns without fire protection were investigated.Fire tests were carried out to study the fire behaviors,section temperature fields,deformations,and fire resistance of bar-reinforced concrete filled steel tubular columns without fire protection.The experimental results indicate that the fire resistance can be obviously increased by the steel reinforcement allocated in the columns.The numerical method to simulate the fire resistance of bar-reinforced concrete filled steel tubular columns was discussed,and the effects of water,contact thermal resistance,and transient thermal strain were taken into account in this method.Calculated results were compared with experimental values demonstrating that the numerical method is capable of calculating the deformations and fire resistance of the columns with an accuracy that is adequate for practical purposes.Finally,simplified calculation methods,which are convenience to practices,were presented on the basis of numerical and experimental results to calculate the section temperature field and fire resistance of bar-reinforced concrete filled steel tubular columns.