Have set up a small Fire Training Facility in Florida and have been asked to give the side wind load in MPH.

Unit is 4 steel ocean containers stacked two high side by side and welded together and welded to concrete piers that are 36" deep and 19" in diameter. Whole unit set up is 17' tall x 16' wide x 40' long.

The sides are approximately 640 square feet of flat space and the ends are approx. 272 sq. ft. Total complex weighs about 42,000 lbs.

How do I fiqure what wind speed this complex will take?

Thanks,

Rick

I do not believe there are any structural engineers on board here, so I did a quick search for "side wind load calculations".

Being an electrician, I need to be concerned with the wind load effect on exterior light fixtures and poles, which is relatively small, and simple to calculate, I was curious about your question.

Your situation is definitely much more complicated, as described by the following information:

http://www.aij.or.jp/jpn/symposium/2006/loads/Chapter6_com1.pdf

http://ocw.mit.edu/NR/rdonlyres/Civil-and-Environmental-Engineering/1-051Fall2003/B56746CA-BF5C-4E25-AF42-418CF0C59202/0/rec1wind_eqloads.pdf

Wind Load Design Analysis: ASCE 7-98 (http://umsis.miami.edu/~lpittack/cae614proj.html)

For $110.00, here is a software package that claims to help with calculations "in 5 minutes or less": MECAWind05 (http://www.engineering-software.com/pr/sku27736.htm)

And a "brief" explanation of an example calculation:
http://www.nssa.cc/NSSA/Assoc_standard_files/app_1.PDF


In addition to the wind load on the exposed surface of the structure, I would imagine that the connection of the structure to the "welded to concrete piers that are 36" deep and 19" in diameter" also be of concern.

Thou the static load of 42,000# should certainly be useful, I propose that if the total wind load due to the effective projected area of the structure combined with the wind speed could result in a wind load that could overcome the dead weight of the structure, the actual connection to the ground will be stressed, and should be considered and worked into any calculations.

You don't state how many piers there are, even if there are many, I do not believe that 36" deep piers are sufficient, of course, only if the wind load could actually lift 42,000#.

I get that wind load effect is a concern in Florida due to hurricane wind speed, and that effect on cladded structures that can disintegrate in that wind, but why are the inspectors concerned with a welded steel structure such as a shipping container.

What about all the loose containers stacked and lying around at the ports?

Ahh, now because they are used as a building structure?

I realize I did not actually answer your question, but hope I helped send you in the right direction.

I'm not a structural or civil engineer, so you shouldn't rely totally on me for this. Most of this is based on Physics I (Mechanics) and the problem-solving nature of any engineering field.

Unless I'm mistaken, what you need to consider are the strength of each weld (an absolute expressed in torque), the strength of the pier mooring (also an absolute expressed in torque), and the direct load of the wind against the exposed surface (absolute expressed by surface area and wind speed).

The effect of the load on any of the strengths will be based on the distance between the load and the weld/mooring point... a (relatively) simple moment of force calculation. Once you've found the relative strengths of each stress point, you will be able to find the max wind speed.

Odd geometries of the structure can produce strange results... you should consider specifics in any non-hypothetical case, as the load can vary greatly depending on the angle of the wind relative to the face of the structure.