Value of z for wind per ASCE 7
Value of z for wind per ASCE 7
(OP)
In API-650 we can use ASCE 7 for determine the wind pressure. One of the factors is zg which uses a value of z. In ASCE 7-02 under "Other Structures" z was defined as the centroid of the area under consideration. In ASCE 7-05 it does not seem to say this. For a 40' high tank, should z be at the top of the tank (z = 40) or the centroid of the area (z = 20)?





RE: Value of z for wind per ASCE 7
I have always interpreted the meaning of (z) to be the height where you apply the wind force.
If you have a 40ft tank, your velocity pressure (qz) varies with height.
At 20ft (z) = 20, at 40ft (z) = 40.
This gives you a different velocity pressure exposure coefficient (Kz) at different heights.
I don't see where that has changed in ASCE 7-05
RE: Value of z for wind per ASCE 7
RE: Value of z for wind per ASCE 7