Fragility curves for building envelope components subject to windborne debris impact

This paper presents a methodology for developing windborne debris (WBD) impact fragility curves for building envelope components (BECs) by using stochastic finite element (FE) models. These fragility curves provide the probabilistic description of the impact resistance of BECs subject to an impact event described by an appropriate intensity measure (IM). Accurate fragility curves are essential in the development of a general probabilistic performance-based engineering framework for mitigation of WBD impact hazard. Carlo simulation is used in combination with the FE method to propagate uncertainties in the BECʹs model parameters and WBD impact location. As an application example, the fragility curves relative to different damage states are derived for aluminum storm shutters subjected to WBD impact. It is found that (1) the missile kinetic energy at impact is a sufficient IM for BECs with ductile behavior subjected to WBD impact, and (2) the performance of storm panels in terms of penetration of WBDs is critically dependent on the details of the panels’ installation.