Wall sandwich panels with steel facings and PUR foam core under transverse loading: Experimental testing and numerical model calibration

Light weight panels are largely used for the envelope (wall assembly, roofing system) of different kind of buildings. Under extreme loading conditions, like external explosions, the walls may suffer extensive damage, under either positive or negative pressures. The study presented in the paper describes the results obtained on wall sandwich panels tested for transverse loading until complete failure. The panels are arranged as single span systems supported on side rails and loaded at the mid-span. After a quasi-linear response, the maximum bending capacity is reached. At this point, the panels have a sudden drop in capacity, associated with the rapid wrinkling of the face in compression. If the end fasteners have adequate resistance, catenary stage develops, and the ultimate capacity can be significantly higher than the peak bending capacity. Flexibility of the lateral restraints significantly influence the initiation of catenary action and the ultimate capacity of sandwich panels. Numerical models were calibrated using the structural analysis and design program SAP2000. This may allow professionals to integrate more quickly the wall models into the structural design even for extreme loading conditions.