Composite Slab Behavior and Strength Analysis. Part I: Calculation Procedure

Abstract

A new calculation procedure is described that provides an alternative to full-scale testing for composite slabs with ribbed decking used in buildings. The procedure consists of combining shear-bond test results with a numerical analysis to predict the behavior and strength of composite slabs. It may be used to analyze either single spans or multiple spans. The procedure incorporates certain simplifications and assumptions that allow for reasonable yet conservative prediction of both behavior and strength. In particular, chemical bonding between the concrete slab and decking and concrete tension behavior are ignored because they are brittle in nature. Advantages of using this procedure rather than full-scale test results are versatility and reduced cost, the estimation of deformations at working loads, the inclusion of additional variables such as end anchorage (over the end supports), additional positive moment reinforcement (in the span), and reinforcement in negative moment regions (near interior supports). This calculation procedure may also be used for the development of new decking and to improve the performance of slabs with existing decking. Examples of calculations are presented for single-span composite slabs.