Study on the fire performance of novel G550 galvanized steel‐concrete composite slabs

To reduce the construction and maintenance difficulties caused by fire proof coatings and reinforcement used in composite structures, 2 new types of steel‐concrete composite slab was proposed combining G550 galvanized steel with re‐entrant sheeting and closed profiled sheeting. 12 full‐scale standard fire tests were conducted to investigate the fire performance of G550 galvanized steel‐concrete composite slabs. Temperature rise within profiled sheeting and concrete are compared for the novel composite slabs. With the development of bearing capacity index, the fire performance of novel G550 galvanized steel‐ concrete composite slabs are analyzed under the same unified standard. Results showed that all the newly developed composite slabs could reach the design requirements for buildings up to 18 m above ground without the use of coatings and reinforcement. And the composite slabs with closed profiled sheeting can reach 120 min fire resistance when bearing capacity index is less than approximately 0.1 and are suitable for application in high‐rise buildings.