Structural Performance of Prestressed Composite Members with Corrugated Webs Exposed to Fire

In this study, to assess the fire performances of corrugated webbed prestressed (CWPS) composite beams exposed to fire, full-scale fire resisting tests were carried out, and fire-resisting behavioural responses of the test specimens were analyzed and compared with those obtained from nonlinear finite element analyses. Key test variables were the cover thickness of the fire protection material applied to the bottom flange of corrugated webbed steel beams, which was directly exposed to fire, and the shapes of corrugated webs. All the composite beams with fire protection material covers exposed to standard fire showed good fire-resisting capacities with fire ratings over 3 h and in particular, CWPS composite beams with relatively thin fire protection material cover thickness, compared with the non-prestressed slim-floor composite beam, satisfied the required fire performance criteria in ISO 834 standard and Eurocode. Additionally, the test results showed that the shape of corrugated webs used in CWPS composite beam specimens could have a great impact on their fire-resisting performance. The nonlinear finite element analyses performed in this study accurately estimated the overall behaviours of test specimens and especially assessed the effects of the shape of the corrugated web on the temperature distributions and fire resistance performances of CWPS composite beams appropriately.