Composite slabs micromechanics characterization of the steel - concrete interaction with finite element models

Abstract

This study focuses on the improvement of composite slabs characterization throughout the use of advanced finite elements models. The accurate three-dimensional modelling of a full scale commercial steel sheet and concrete slab geometries enables the analysis of the composite slab micromechanics. The inclusion of the embossments depth and slope, the steel sheet thickness, the tilting angle, the length and width and spacing of embossments, and the profiling angle of the rib shape removes the need of simplifications for the complex phenomenon at the steel – concrete interface. The accuracy observed at the finite element models once compared with the laboratory specimens enables a new approach to describe the complex stress distributions in composite slabs. In particular, this study introduces a novel representation of the longitudinal shear strength tu and a newly defined vertical normal stress σu between the steel and concrete that frequently define the overall composite slab bearing capacity. Subsequently, this study compares detailed stress diagrams and deformations from the finite elements models with experimental data obtained through piezoelectric gauges at the laboratory specimens.