Help with ASCE 7-05 Chapter 6

[pflow]

I am a mechanical engineer interested in learining ASCI 7-05 Chaper 6. I apologize for my following rudimentary questions.

I would like to figure out how to solve a basic problem: determine the wind loads on a foundation for an enclosed box shaped building with roof slope less than 5 degrees.

After struggling to read this code, the following was the method I was going to try to apply:

1. Evaluate Equation 6-15
2. Evaluate Equation 6-18.
2.1 Use GCpl = +,- 0.18 from Figure 6-5.
2.2 Use GCpf = 0.4 from Figure 6-10. I could not figure out what the 1E through 4E surface are. Please explain.
3. Multiply the result of Step 2 by the side with the largest projected area.

Please let me know if I am on the right track or off in left field.

 

[flight7]

My first suggestion is to use Method 1 for a simple building. But if you want to use Method 2, you're on the right track.

The 1E-4E surfaces are the "end zones" where the building is experiencing a higher wind intensity. This location varies based on the wind direction. You need to evaluate each possible wind direction, which is illustrated by the multiple diagrams in Figure 6-10. The end zones create a non-symmetric net load, which induces torsion in the building as a whole. There is some discussion of this in the commentary at the back of the book. This isn't a big deal if the building is symmetric.

For a small building that isn't very tall, I will often disregard the difference between qh and qz, and will use qh in all cases. This simplifies matters and is conservative, but usually not excessively so.

 

[pflow]

Thank you flight7. I appreciate the help.