A folded plate method of analysis for profiled steel sheeting in composite floor construction

Abstract Composite flooring systems incorporating cold formed profiled steel sheeting as both permanent formwork and tensile reinforcement are becoming widely adopted for high rise buildings. Research has shown that the performance of the sheeting alone in supporting the weight of wet concrete during construction frequently governs the design. This paper concentrates upon this aspect of the behaviour and describes the application of the elasticity method, derived from folded plate analysis. The method allows the important deformations due to ponding and transverse bending to be taken into account accurately; such deformations are treated empirically, or ignored, in current design codes. Comparisons with the summarised results of many tests establish the accuracy of the folded plate method and indicate the limitations of the codes. Folded plate analysis is also used to illustrate several aspects of behaviour, particularly the possible movements at the lapped joints between adjacent sheets.