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.