Transverse reinforcement optimization of a precast special roof element through an experimental and numerical procedure

The transverse behavior of a long span three-plate precast roof element is investigated by means of an experimental and numerical research. The performed study highlights that the failure mode of this folded-plate element is strongly influenced by the amount of transverse reinforcement in the wings. This latter is usually designed through simplified methods, which often lead to over-dimensioning in terms of steel welded mesh. To avoid excessive costs for the producers, transverse reinforcement optimization should be required. In this work, a non-linear FE modelling was applied for this purpose. The reliability of the followed numerical procedure was first verified by an initial type testing (i.e. experimental load test up to failure). The agreement between numerical and experimental results showed the efficiency of the model in simulating all the main sources of non-linearity related to both material behavior and element geometry. Numerical analyses were so used to perform a parametric study as a function of transverse reinforcement amount, aimed at determining a coefficient of “model inaccuracy”. This coefficient should be used as a correction factor for the element design in routine calculations based on beam theory.