标准升温下轻钢-混凝土组合梁的抗火性能研究

对标准升温下轻钢一混凝土组合梁的抗火性能进行了研究：采用ANSYS软件计算了轻钢一混凝土组合梁截面的温度场；采用数值算法计算了轻钢-混凝土组合梁的全过程曲线；采用抗力折减系数法分析了轻钢-混凝土组合梁的承载力在火灾下的变化情况；同时分析了各参数对温度场分布、全过程曲线及抗力折减系数的影响．结果表明：由于混凝土的吸热作用，钢梁的温度明显低于无混凝土时的裸钢构件；影响全过程曲线和抗力折减系数的主要参数是梁高和钢梁厚度，而其他参数影响较小；抗力折减系数的变化在后期比前期剧烈一些．理论分析结果得到了有关算例的验证．

Behavior of Lightweight Steel-Concrete Composite Beams Subjected to Standard Fire

This paper studied the behavior of lightweight steel-concrete composite beams subjected to standard fire. The finite element method was applied to calculate the temperature field of lightweight steel-concrete composite beams. By using a numeric method, the full curve of the members subjected to standard fire was calculated, the load resistance ratio was studied, and the related factors about those subjects were also derived. Results showed that, due to the heat absorbed by the concrete, the temperature field was lower than that of unprotected steel structure; that the main factors related to the full curve and fire resistance load ratio were the thickness and the height of the steel beam; and that the fire resistance ratio decreased more significantly at the anaphase than at the initial period. The calculated results were verified by case studies from other documents.