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ScafEng
Aug 21, 2008, 01:22 PM
How do you calculate wind loads using ASCE 7-05 for the following structure?

A monoslope roof over an open structure. Height = 10', width = 5', length = 100'

Lets say wind speed = 90 MPH, Exposure "B".

The problem comes with the h / L value. In this case it is 2.0 which falls outside of the range of the table in the code.

Question: How do I use the code for this structure?

Newton1Law
Jul 20, 2010, 11:54 AM
Often the angle is used to calculate the effective area exposed to the wind. If H/L is 2, then your saying the Height=10' and the length = 5'. The exposed horizontial equalivent perpendicular surface would have a 1000 sq.ft. At 29.92 In-Hg and temperature of 77 degrees F, the wind would produce a 21.845 Lb/Ft squared pressure or about 11 tons of pressure. Seems high though.

Hope this helps,

Newton1Law

bscusa
Aug 27, 2013, 07:00 AM
The building will be considered open so the GCpi will be affected. The rest is math. 11 tons of pressure from Newton1Law is not close.

I need to know the slope of the roof to complete the calcs. The pressure on the roof can be handled, it's the horizontal component of the shear that is going to hurt you.