The "Guide to the Use of the Wind Load Provisions of ASCE7-02" has the formulas. Newer version should have it as well. They are in the same form as the other formulas ( constant + coefficient * log( area ) ).
It is probably a coincidence that the checks on the middle column (picture 4) align with the inside edge of the support beam. Could what little load has actually been applied compress the column unevenly and expand the existing checks?
It won't change the results for this one, but may trip you up in the future. The enclosed check appears to follow check 2a. It should be the opposite of check 2a, since the enclosed check should be less than minimum opening size.
Just looking at the screenshot, you have the mislabeled values for Aoi and Agi, which might cause some confusion. Aoi is the sum of the openings in all the other surfaces. Agi is the sum of all the other surfaces areas.
Your 2a check has the comparison the wrong way. Surface opening greater...
With buildings that are open on three sides it depends on the geometry of the building whether it will be "partially enclosed" or "partially open" and I just have to calc it.
"Open" and "Partially Enclosed" have used the same formula for a very long time. So "open" in 7-10 and 7-16 are the same. Before 7-16 "Enclosed" was the catch all enclosure classification. This was a point of confusion for many (How is this building enclosed when I can see though it?). In...
Exposure is done based on each cardinal direction. Enclosure is done based on building surface area. You should find a copy of "Guide to the Use of the Wind Load Provisions of ASCE 7" to be highly informative.
Just looking at that porch says its partially enclosed.
It is section 1926.756(c)(1) in OSHA 1926 Construction.
Skimming through AISC 341, it does not appear that there is any additional requirements for this joint. You should review this for your self to see if there is something applicable.
They can share bolts, but you need to provide at least one unshared bolt, possibly for each beam. This is so the weight of the beam can temporarily hang from the one bolt until the other beam can be installed. In the USA this is covered in OSHA.
1. Use a weighted average of the total areas. This was done in one of the studies that this code is based on.
2. I'm fairly sure that chapter 29 does not apply in this case.
I've only using this strapping going straight from flange to flange (not crossing). Its a lot easier for the erector to not have to weave the strapping through the purlins.
You could calc the purlins with one flange attached to panel and not have the strapping at all. That B-deck will be...
LGSI sections are pretty much the standard that you would get when ordering ZEE sections. These come with one flange about 1/4" wider than the other to allow lapping.
The MBMA design guide will still be useful even if you are not designing a metal building. It will have examples on how to...
