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Wind Direction and Hurricane-Induced Ultimate Wind Loads.


pdf icon Wind Direction and Hurricane-Induced Ultimate Wind Loads. (788 K)
Simiu, E.; Heckert, N. A.

European and African Conference on Wind Engineering (2 EACWE), 2nd. Proceedings. Volume 2. June 22-27, 1997, Genova, Italy, Solari, G., Editor(s), 1825-1831 pp, 1998.

Journal of Wind Engineering and Industrial Aerodynamics, Vol. 74, No. 76, 1037-1046, 1998.

Keywords:

wind direction; structural engineering

Abstract:

A consensus on the wind directionality issue is needed for the validation by building officials of the wind-tunnel procedure allowed by the ASCE 7-95 Standard, and for the development of knowledge-based standard provisions for wind loads. As a contribution to the debate needed to achieve such a consensus we describe an updated method for estimating wind loads that takes into account the directional dependence of the aerodynamic coefficients and the extreme wind climate, and uses the 'peaks over threshold' approach for the estimation of extremes. For hurricane-prone regions, we estimate mean recurrence intervals (MRIs) of ultimate wind loads obtained from 50-yr loads via multiplication by a factor specified by the ASCE 7-95 Standard. For typical aerodynamic coefficients with strong directional preference, depending upon location and building orientation the estimated MRIs of the ultimate wind loads varied betwwen less than 1,000 to more than 10,000 years. We also found that for loads with very large MRIs the common practice of disregarding direction effects is not necessarily conservative from a structural engineering viewpoint.