Experimental Tests and Numerical Simulations of Stiffened Pure Aluminium Shear Panels

摘要

The protection of buildings against seismic damage is based on inserting into the primary framed structure special devices acting as hysteretic and/or viscoelastic dampers. Shear panels really represent a convenient system for passive seismic protection of framed buildings for low and high intensity earthquakes thanks to their remarkable lateral stiffness, limited elastic strength, high hardening and large ductility. Recently, a wide experimental and numerical programme has been undertaken at the University of Naples 'Federico II' in order to investigate the energy dissipation capacity of aluminium alloy shear panels, suitably reinforced by ribs to prevent shear buckling both in the elastic and plastic field. As applied material, the pure aluminium (EN-AW 1050A) has been chosen because of its very low strength, large ductility, low specific weight and availability on the market. Experimental cyclic tests on 1000×1500 mm aluminium shear panels, characterised by different stiffeners configuration, have been carried out. To simulate the monotonic and hysteretic behaviour of the systems, according to the experimental tests, a sophisticated FEM model has been set up. The comparison between experimental and numerical results shows that the proposed model is reliable enough to well interpret a number of important behavioural phenomena in terms of the main global features of the system (energy dissipation capacity, global secant stiffness and equivalent damping ratio). On the other hand, it has been noted that the proposed model is not able to well interpret the very early stages of the loading process, but this should be due to the fact that the effect of the residual stresses is not contemplated due to the lack of experimental data. Further improvements of the numerical model throughout this direction are desirable.