Fire safety assessment of super tall buildings: A case study on Shanghai Tower

Shanghai Tower is an existing super high-rise building composed of mega frame-core-outrigger lateral resisting systems. Its structural safety in fire has been given great attention. This paper presents an independent review of the performance of Shanghai Tower in case of fire. Two fire scenarios: standard fires and parametric fires have been considered. The fire resistance of key component, including the concrete core, mega columns, the composite floor, outrigger trusses and belt trusses were examined first. Their real fire resistance periods proved to be far beyond the design fire resistance. The components with weak fire resistance such as peripheral steel columns and web members of belt trusses were then removed to study the resistance of the residual structure against progressive collapse. The results show that Shanghai Tower has a minimum of 3 h fire resistance against fire-induced progressive collapse. The concrete components have smaller residual displacements compared to the steel components. It is recommended, for the design of other similar structures, that effective fire protection should be provided for the outrigger trusses to guarantee the connection between the core and mega columns.