Damage modelling of aluminium panels impacted by windborne debris

Abstract

Impact by flying debris in windstorms conditions has been a major contributor to damage to aluminium and other types of building facades. The damage so caused to cladding panels was mainly controlled by the amount of force that was developed at the point of contact between the debris object and the surface of the target. However, no codified design guidelines are currently available to quantify the required impact resistance of an aluminium panel for given storm scenarios. Current analytical expressions derived for analysing impact actions as reported in the literature are mostly based on the use of energy principles. The influence of the hardness of the debris object and the magnitude of the contact force has not been taken into considerations. Thus, the amount of deformation that is inflicted on the panel by the impact of a non-rigid projectile object can be over-stated. This paper presents an analytical expression that has been developed for estimating the severity of damage to the surface of a cladding panel (and to determine if leakage of rainwater from the panel can be resulted) for given mass of the debris object, velocity of impact, and importantly, parameters characterising the stiffness properties of the impactor object.