Velocity Pressure Equation
Velocity Pressure Equation
(OP)
Hi everyone,
I'm analyzing a machine to be mounted atop a building, and need to determine the wind load acting on the machine. In ASCE 7-10, the equation for velocity pressure qz is
qz = 0.00256*kz*kzt*kd*V^2
In this equation, what value is V: Vult (from the basic wind speed map) or Vasd? (Vasd = Vult*Sqrt(0.6))
I have a Risk Category II structure in Exposure B, located in the upper midwest. According to the building code official, the design wind speed is 90mph. However, the wind speed map (which is for Exp C, mind you) says V = 115mph. Any help would be appreciated.
(I know I'll need to determine the factors G and Cp as well. But this first step has tripped me up.)
I'm analyzing a machine to be mounted atop a building, and need to determine the wind load acting on the machine. In ASCE 7-10, the equation for velocity pressure qz is
qz = 0.00256*kz*kzt*kd*V^2
In this equation, what value is V: Vult (from the basic wind speed map) or Vasd? (Vasd = Vult*Sqrt(0.6))
I have a Risk Category II structure in Exposure B, located in the upper midwest. According to the building code official, the design wind speed is 90mph. However, the wind speed map (which is for Exp C, mind you) says V = 115mph. Any help would be appreciated.
(I know I'll need to determine the factors G and Cp as well. But this first step has tripped me up.)






RE: Velocity Pressure Equation
RE: Velocity Pressure Equation
RE: Velocity Pressure Equation
Thanks for the prompt reply. They're using a state building code that references ASCE 7-10. I'm disturbed that the building code official I spoke with has told me that the design wind speed is 90mph. Regardless, which value should I be using in the equation for V, 90 or 115?
Also, is this regardless of the exposure category? (Recall that the wind speed map is for exposure category C, while my project is in Exposure B. Perhaps the other factors in the equation account for the different exposure category?)
RE: Velocity Pressure Equation
The exposure is adjusted with the kz (kh) coefficient.
RE: Velocity Pressure Equation