Experiments on composite steel beams with precast concrete hollow core floor slabs.

摘要

Precast concrete hollow core floor unitsudare frequently used in multistorey steel-udframed buildings where they bear on to theudtop flanges of universal beams. The steeludbeam is normally designed in bending inudisolation from the concrete slab and noudaccount is taken of the composite beamudaction available with the precast units.udAlthough some commercial data are avail-udable, there is no general design guidanceudto cover the wide range of material andudgeometric variables found in this form ofudconstruction. This paper summarizesudresearch carried out at the University ofudNottingham on this form of constructionudand presents the results of three full-scaleudbending tests of steel beams acting com-udpositely with proprietary precast hollowudcore slabs. The 150 mm deep units wereudattached to the universal beams throughud19 mm diameter headed shear studs, andudtested in four-point bending over a span ofud6 m. For typical geometry and serial sizesudthe composite beams were found to beudtwice as strong and nearly three times asudsti as the equivalent isolated steeludbeams. The failure mode was ductile, andudmay be controlled by the correct use ofudsmall quantities of tie steel and in situ infilludconcrete placed between the precast units.udTo generalize the findings, isolated push-udoff tests and eccentric compression testsudwere used to study the horizontal interfaceudshear resistance of the headed studs andudthe strength of the slab, respectively.