Design Gust Wind Speeds in the United States.
Design Gust Wind Speeds in the United States.
(577 K)
Simiu, E.; Filliben, J. J.
Journal of Structural Engineering, 1077-1080, September
1999.
Keywords:
wind velocity; climate; structual design; statistics;
structural engineering
Abstract:
The main result of the authors' work is Fig. 5, a map
containing 5O-year peak gust wind speeds specified for
structural design purposes. Except for (1) the states of
California, Oregon, and Washington; (2) areas affected
by hurricanes; and (3) a few small special wind regions,
that map specifies a wind speed of 90 mph (40 m/s)
regardless of geographical location. The question arises
whether the true 50-year peak gust speeds are indeed
close to 90 mph (40 m/s) over that entire geograph-ical
area, or whether the map is in fact masking real
differences among distinct extreme wind climates. The
contours of the 50-year map based on the authors' own
calculations (Fig. 3) contain estimated speeds varying
from 80 mph (35.8 m/s) in northern Minnesota and
Wisconsin to 95 mph (42.5 m/s) in portions of Oklahoma
and New Mexico. The difference between the largest and
the smallest estimated speeds is almost 20%; if, as is
done by the authors. we consider the difference in terms
of the corresponding wind loading. the percentage is
about 40%.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899