Slenderness study of composite slabs modeled by explicit dynamic procedure

Abstract

Composite slabs are popular flooring systems in steel-framed buildings. They have a lot of advantages which make their use the most feasible option in many situations. Slenderness ratio (shear span/effective depth) has a dominant effect on composite slabs. It is not possible to test the whole range of slenderness for each deck profile because of limitation in time and cost. A good understanding of the slenderness effect makes prediction of the slab strength possible, and contribution to such understanding was the main aim of this study. A nonlinear finite element model was employed to predict the behavior of composite slabs. Steel-concrete interface was modeled with cohesive elements and a quasi-static solution was achieved through explicit dynamic analysis. Modeling procedure was improved to avoid unnecessary computational cost. The study then focused on examining the behavior of composite slabs with respect to variable slenderness. It is found that at slenderness ratio 7.0, the slab behavior changes between compact and slender. Finally, the study explored the use of shear bond-slenderness equation by plotting a linear regression line. The application of shear bond-slenderness equation enables the prediction of the shear-bond strength of any number of slabs utilizing the same profile from only two sets of test data. It was demonstrated that the shear bond stress varies linearly with the slab slenderness, with slender slabs exhibiting lower shear bond stress.