Development of innovative hybrid sandwich panel slabs: Advanced numerical simulations and parametric studies

An innovative hybrid sandwich slab for the rehabilitation of floors in old masonry buildings was conceived, designed, and tested. This structural system is a lightweight composite floor consisting of bottom skin and shear ribs in Glass Fiber Reinforced Polymer (GFRP), a top layer of Deflection Hardening Cement Composites (DHCC), and Polyurethane foam core. In the first part of this study, the material/structural performance of the panel's concept was assessed by experimental tests. The second part is now dedicated to the execution of advanced numerical simulations, including parametric studies, for assisting on the optimization of this composite slab system and investigating the influence of the relevant characteristics of GFRP and DHCC components. The influence of considering orthotropic behavior for the GFRP components and linear or nonlinear behavior for the DHCC are also investigated numerically in terms of accomplishing serviceability and ultimate limit state requisites for this structural system. The parametric studies show that the thickness of GFRP rib is the most important parameter to increase the load carrying capacity of this type of slabs. Based on the results of these parametric studies, two slabs are built and tested experimentally, and the obtained results are not only used to demonstrate the effectiveness of the developed structural system, but also to appraise the predictive performance of the constitutive models adopted in the FEM-based simulations.