Ultimate Wind Loads and Direction Effects in Non-Hurricane and Hurricane-Prone Regions.
Ultimate Wind Loads and Direction Effects in
Non-Hurricane and Hurricane-Prone Regions.
Simiu, E.; Heckert, N. A.
Environmetrics, Vol. 9, 433-444, 1998.
wind velocity; building technology; climatology;
climate; extreme value statistics; structural
We use 'peaks over threshold' approach to estimate
extreme wind loads calculated by taking into account the
directional dependence of both the aerodynamic
coefficients and the extreme wind climate. Our interest
is focused primarily on ultimate wind loads, that is,
loads that are sufficiently large to cause member
failure. For non-hurricane regions (1) we comment on
issues raised by the fact that directional data
published by the National Weather Service are
incomplete, and (2) note that, owing to the relatively
small sizes of the data samples, results on directional
effects for mean recurrence intervals longer than a few
hundred years are inconclusive. For hurricane-prone
regions we show that, on average, the common practice of
disregarding wind directionality effects is conservative
for 50-year wind loads. However, according to our
results, the degree of conservatism decreases as the
mean recurrence interval increases. While individual
estimates of speeds with very long mean recurrence
intervals are unreliable, statistics based on estimates
obtained from large numbers of records can provide
useful indications of average trends and suggest that,
for mean recurrence intervals associated with ultimate
wind loads, the favorable effect of wind directionality
tends to be marginal.