钢筋混凝土框架结构火灾反应分析

Fire Response Analysis of Reinforced Concrete Frames

在钢筋混凝土框架模拟火灾试验和混凝土高温下本构关系试验基础上，根据不稳定热传导理论和非线性直接刚度法，对钢筋混凝土框架在火灾进程中的温度反应和结构反应进行了非线性有限元分析．其中，考虑了钢筋的存在对温度分布的影响以及混凝土和钢筋在高温下的卸载规律对结构内为重分布所起的重要作用和高温瞬时徐变的影响．通过试验结果和理论分析的对比，得出了有益的结论．

On the basis of the pseudo-fire tests of reinforced concrete frames and tests of constitutive relations of concrete under high temperatures, nonlinear finite element analyses of temperature and structural responses of reinforced concreteframes during a fire were conducted according to the unstable heat transfer theory and nonlinear direct stiffness method. The influence of the steel bars to the temperature distribution and that of the stress-strain relationships for concrete and steel after decrease of strain to the redistribution of internal forces and that of transient creep under high temperatures were considered. Based on the comparison between the test results and analysis, valuable conclusions were reached.