Numerical Investigation on Shear Bond Improvement of High Performance Concrete Composite Slabs Containing Recycled Aggregates

Composite slab with profiled metal decking provides economical solutions for floors of steel framed building systems particularly due to its reduced dead weight. The ability of the slabs to act compositely is governed by the shear interaction between the concrete topping and the profiled steel deck. The longitudinal shear bond failure is reported to be the most common failure mode in composite slabs. Significant end slips occur between concrete and profiled steel sheeting interfaces even before reaching its ultimate bending capacity. The present study aims at investigating various bond improvement methods for a composite slab with High Performance Concrete (HPC) topping containing recycled aggregates from demolition waste. The materials for longitudinal shear bond improvement under consideration includes nitobond, saw toothed steel and eye hooks. Percentage replacement of recycled coarse aggregates were first optimised and the analysis of composite slab after bond improvement is done numerically for different configurations of various shear connectors from which shear strength is computed using codal m-k method. The composite slab under consideration exhibits better performance in terms of load carrying capacity and shear strength compared to normal concrete composite slab. It also reflects in a reduced deflection and end slip.