Vulnerability and Structural Capacity Assessment of Historic Glass Facades under Bird-Strike

Bird-strike analysis is of particular relevance for aircraft engineering applications, where major wing or fuselage components may suffer for possible collision during flying stage and result in serious structural damage. To this aim, the Federal Aviation Regulations requires dedicated bird-strike resistance assessment tests and certifications. In building applications, glass is also largely used for vertical and horizontal load-bearing components. In such a kind of structural design context, major attention is given to wind pressure, seismic loads, impact due to crowd and human body (i.e., to prevent falling out), or even explosions, and rather null consideration is posed for bird-strike analysis, due to their expected limited impact forces and effects on glass. This paper investigates such a topic giving evidence of the dynamic response of an existing glass facade built in 60 s as a part of a museum in Italy. The vulnerability analysis is carried out with computationally efficient Finite Element (FE) numerical models of consolidated use for bird-strike, based also on preliminary mechanical characterization from in-field geometrical inspection and Operational Modal Analysis (OMA) experiments. Local and global dynamic effects due to localized bird-strike on the examined glass facade are discussed based on parametric numerical analysis from Coupled Eulerian Lagrangian (CEL) method.