Relationship between specified ductility and strength demand reduction for single degree-of-freedom systems under extreme wind events

Abstract

Structural failures could be attributed to extreme wind events, such as hurricanes, tornadoes and wind bursts. These events with very low probability of occurrence should be properly included in the structural design. Large magnitude forces, greatly exceeding the ordinary wind storm loads, mean that considering extreme wind loading will result in increased cost for the structural design. An alternative design approach consists in dissipating the energy coming from the extreme wind event through the hysteretic behaviour, in a similar measure as what is used in earthquake engineering. This paper aims at establishing the relationship between the desired ductility of the structures and the reduction in structural strength required to withstand extreme wind events in order to reduce the cost of structures. Digitally generated wind as well as in situ measurements of winter storm and hurricane wind are used in this study. The study focused on single-degree-of-freedom (SDOF) systems to represent a wide range of structural behaviour. A simplified linearized method to estimate nonlinear response is proposed here. The applicability of the present study on real wind records is verified.