The effects of temperature variations on the long-term behaviour of composite steel–concrete beams

The long-term behaviour of composite steel–concrete beams is presented. The general case of continuous beams with deformable connectors between steel beam and concrete slab is studied, as well as the peculiar case of simply supported beams with rigid connectors, which reduces to a sectional analysis. Diurnal and seasonal temperature variations are taken into account and the importance of correctly evaluate their effects, which can cause concrete cracking even in the presence of a positive bending moment, is shown. The analysis is performed in the viscoelastic domain, referring to the constitutive Volterra integral equation to describe the delayed behaviour of concrete.