Shear capacity of prestressed hollow core slabs in slim floor constructions

Research in Finland and Germany reveals that the shear strength of hollow core slabs is reduced considerably due to transverse stresses when the slabs are bedded on flexible supports (e.g. slender beams). The aim of the present investigation is to analyse the load bearing behaviour of hollow core slabs supported on shallow steel beams, so-called slim floor constructions. This paper describes four full-scale tests on two-span floor systems and reference tests on single slabs with rigid supports. The observed shear strengths are compared with predicted failure loads according to international code provisions. Finally, recommendations regarding the design and the construction on flexible supports are given.