Environmental Engineering Reference
In-Depth Information
Fig. 2.3 Average wind speeds for various wind zones
Figure 2.3 shows the associated wind speed profiles.
The gust response factor (G) is related to the average dynamic pressure q
m
. DIN 1055-4
[12] C.3 (1) contains the following formula:
q
Q
0
þ
R
x
G
¼
1
þ
2
g
I
v
z
ðÞ
where
I
v
(z
e
)
turbulence intensity at effective height z
e
(Table 2.4)
z
e
reference height (see DIN 1055-4 [12] Figure C.1) [m] (z
e
¼
0.6
h applies for
towers of height h)
g
peak factor
Q
0
quasi-static component (basic gust component) of gust response
R
x
resonance component of response as a result of gust response
These parameters are explained below.
Figure 2.4 shows the associated turbulence intensity profiles.
Table 2.4
Turbulence intensity (to DIN 1055-4 [12] Table B.2)
Þ
f
I
v
z
ðÞ¼e
ð
z
e
=
for z
e
<
10
or
I
v
;
max
z
min
Terrain category
I
II
III
IV
Factor
e
0.14
0.19
0.28
0.43
Exponent
f
0.12
0.16
0.22
0.30
z
min
2.00
4.00
8.00
16.00
I
v,max
0.20
0.22
0.29
0.37
