Dear COADE staff,

Hello, I have a question for Wind Load.

According to ASCE 7-02, Wind Force is calculated by the following formula:
F = qzGCfAf
where:
F: Wind Force.
qz: Velocity pressure evaluated at height z above ground (N/m2)
qz = 0.613 KzKztKdV2I
Kz: Velocity pressure exposure coefficient evaluated at height z. (taken from Table 6)
Kzt: Topographic factor = 1.0
V: Basic wind speed (m/s)
I: Importance factor (taken from Table 5)
G: Gust effect factor (0.85)
Cf: Force coefficient to be used in the determination of wind loads (Table 7)
Af: Area of building (m2)

G is 0.85 and Cf is 0.7(refer to figure 6-19 of ASCE 7-02)

According to CAESAR II manual, the G Factor is not shown like Follow formula:

F = PeqSA
Where:
F = the total wind force on the element
Peq = the equivalent wind pressure (dynamic pressure)
S = the pipe element wind shape factor
A = the pipe element exposed area as shown in the figure as follows

If formula of ASCE 7-02 is applied, wind shape factor shall be 0.595(G x Cf). However if CAESAR II is applied, wind shape factor shall be 0.7 only.

What's the difference between ASCE 7-02 and CAESAR II?

Please give me the solution if you know about that.

Best regards,