Influence of the Bauschinger Effect on the Deflection Behaviour of Cambered Steel and Steel Concrete Composite Beams

Steel concrete composite beams are an economical alternative for the construction of wide-spanned slender structures in parking lots, office and industrial buildings. They combine the tensile strength and stiffness of steel sections with the good compressive strength of concrete slabs. To ensure an unrestricted use of the building, the expected deformations, vibrations and cracks are calculated during the analysis of the serviceability limit state. In reality, major differences between the calculations and the real deflections of beams are observed. Therefore, the deflection behaviour of composite beams was analysed and recommendations were developed to improve the calculation of the deformations. The deflection history was measured continuously during construction of four parking lots built with steel concrete composite beams. One result was that the fabrication of the beams at the manufacturing plant has an important influence on the subsequent deflection of the beam.