Analysis of hurricane directionality effects using event-based simulation

This paper presents an approach for evaluating directionality effects for both wind speeds andrnwind loads in hurricane-prone regions. The focus of this study is on directional wind loads on low-risernstructures. Using event-based simulation, hurricane directionality effects are determined for an open-terrainrncondition at various locations in the southeastern United States. The wind speed (or wind load)rndirectionality factor, defined as the ratio of the N-year mean recurrence interval (MRI) wind speed (orrnwind load) in each direction to the non-directional N-year MRI wind speed (or wind load), is less thanrnone but increases toward unity with increasing MRI. Thus, the degree of conservatism that results fromrnneglecting directionality effects decreases with increasing MRI. It may be desirable to account for localrnexposure effects (siting effects such as shielding, orientation, etc.) in design. To account for these effectsrnin a directionality adjustment, the factor described above for open terrain would need to be transformed tornother terrains/exposures. A