Experimental behaviour and numerical analysis of floor sandwich panels

This paper presents the second part of an experimental investigation carried out on a construction system based on completed in-situ sandwich panels with non-shear connectors, concerning the study of floor sandwich panels. Four-point flexural tests were carried out on several full-scale panel specimens with different slenderness ratios in order to study the behaviour of panels under vertical loads. Additionally, wall–floor nodes with different connection details were tested to analyze the effective degree of the rotational restraint of different realistic nodes. Furthermore, a loading test on the floor of a full scale 3D mock-up entirely built with sandwich panels was carried out to investigate the service and ultimate behaviour of a real floor. The most significant load-displacement diagrams for increasing load are illustrated and the failure modalities are discussed. The semi-composite behaviour of the panels, guaranteed by the internal layer of polystyrene and the reinforced concrete beams at the panel ends, is highlighted. The effects of the wall–floor connection and the bi-dimensional behaviour of the floor are also evaluated. Finally, some numerical simulations are performed with non-linear finite element models and some useful design indications are given.

► Sandwich panels made of polystyrene layer with two external sprayed concrete layers. ► Loading tests on floor panels, wall–floor nodes and a full scale 3D mock-up. ► Experimental results reproduced with numerical models and simple analytical formulas. ► Flexural behaviour characterized by tri-linear relationship and small uncracked phase. ► Wall–floor connection and floor bi-dimensional behaviour ensure high bearing capacity.