火灾下钢管混凝土柱的耐火极限有限元分析

为研究将轻骨料混凝土作为防火保护层对钢管混凝土柱耐火极限的影响以及保护层厚度实用计算方法,采用有限元方法确定高温下钢管混凝土柱的温度场,通过ABAQUS有限元软件建立钢管混凝土柱的耐火极限模型,分析各参数对构件耐火极限的影响程度,基于数值模拟计算结果,给出在火灾下钢管混凝土柱在工程常用范围内的抗火实用计算公式,将计算结果与相关试验数据进行比较,分析结果表明:将轻骨料混凝土作为防火保护层应用于钢管混凝土柱对其耐火极限有较大的影响;简化公式计算结果与试验数据较为接近,可靠性较高,实用性较强。

Finite element analysis of fire resistance limit of concrete-filled steel tube columns under fire

In order to study the effect of using lightweight aggregate concrete as a fire protection layer on the fire resistance limit of concrete-filled steel tube columns and the practical calculation method for the thickness of the protective layer,the finite element method was used to determine the temperature field of the concrete-filled steel tube column at high temperatures,and the ABAQUS finite element software was used to establish the concrete-filled steel tube column and analyse the influence of each parameter on fireproof limit of component.Based on the numerical simulation calculation results,the practical calculation formula for the fire resistance of concrete-filled steel tube columns in the common engineering range under fire was given,and the calculation results were compared with related test data.Comparison and analysis results showed that the application of lightweight aggregate concrete as a fire protection layer to concrete-filled steel tube columns had a greater impact on the fire resistance limit,the simplified formula calculation results were closer to the experimental data,the reliability was higher and the practicability was stronger.