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Steel I beam piers. to submerged or not submerge? 1

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angie1111

Structural
Dec 1, 2005
3
My husband and I are building a pier deck out of 4" steel I beams. They will stand 20' tall and connect onto other ridge beams. We have a difference of opinion. My opinion is the steel I beam should be submerged into concrete but he seems to think the I beams can stand on top of a concrete pad and anchored to a bolt coming up from the concrete pad. I cannot image standing a 20ft I beam up with such a small bolt. Who do you think has a more stable idea about how to set the steel I beam piers?
 
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First off, you should hire an engineer. 4" I beams are pretty slender for a 20' rise. They will need to be cross-braced to make sure they won't buckle.

Look into a 4 bolt connection.



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"...students of traffic are beginning to realize the false economy of mechanically controlled traffic, and hand work by trained officers will again prevail."

Wm. Phelps Eno, ca. 1928
 
I guess my husband and I were both wrong. We would love to hire an engineer but it's just not that easy here in the southern coast of Oregon. Engineers are in high demand because of a building boom out here and most don't work in the residential field. Even if I could find one they would take one look at our old farmhouse built in the 1900s on the side of a hill and run the other direction as did the contractors I attempted to hire.
I sure appreciate the tip about a 4 bolt connection. You know there is a huge lack of information regarding structural engineering. If an engineer was to write a book in laymen's terms I think it would sell quicker than a book store could keep it on the shelf. I could not even find a standard chart that would tell us how much weight certain sizes of steel I beams could support. Even the lumber industry has charts floating around for various sizes of lumber. Oh well....as I said before, thanks for the tip.
 
If I were you, and I couldn't find an engineer, an architect would be my second choice.

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"...students of traffic are beginning to realize the false economy of mechanically controlled traffic, and hand work by trained officers will again prevail."

Wm. Phelps Eno, ca. 1928
 
Standard charts for slender compression members don't exist.

California's population pressure blowing through the Northwest.

That is a funny qote, thanks ACtrafficengr.
 
First to address the question -

Each form of connecting the steel beam to a concrete foundation shaft has it's own merits. Do you want to transfer moment into the foundation or not? Of course, this may be answered by the codes that are applicable to your case, so you may not have a choice.

Secondly, the timber industry is notoriously conservative construction. As such you can find much on the use of timber in structural uses and you don't have to be an engineer to read that information.

Other materials are not so simple, as such you will not find an abundance of information for lay people. The improper use of such design aides by lay people would increase the lawsuits against engineers many times over.

Lastly, It must be problem with work load, 'cause engineers don't run from anything remotely challenging. Quite the contrary - we run from the mundane.

PS I would never hire an architect.

Regards,
Qshake
[pipe]
Eng-Tips Forums:Real Solutions for Real Problems Really Quick.
 
Qshake - come to think of it, siesmic events wouldn't be out of the question in Oregon, would they? You're right - definitely get an engineer.

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"...students of traffic are beginning to realize the false economy of mechanically controlled traffic, and hand work by trained officers will again prevail."

Wm. Phelps Eno, ca. 1928
 
Qshake:

Yes, I do understand the liability of a book for laymen's would be great, however there are so many how to books over subjects just as risky, there must be a way to alleviate this type of liability.
You are correct about the engineering workload. The engineers are swamped and swamped with customers who sold their home in California (or wherever) for twice maybe even triple what homes sell for up here so writing a check and paying in full for the service isn't even a thought.
My family and I can't compete with a customer base like that. It's not just the engineers who are swamped it's every contractor that has anything to do with building homes.
I'm not complaining, just pointing out the realities of where I live. So we can't hire our home renovating projects out...the good news is when we are done our home will have appreciated immensely because of the high demand of real estate in the area.
To get back to my original question I think we have it figured out. Thanks for your input
 
I would see if there is a structural engineer at your church that might give you some basic advice about your job for a nice Sunday afternoon dinner. Your question is too technical to sort out on this forum. We could solve your problem, but we would have to ask a load of questions and you may not understand the answer. That being said, a 4 inch nominal shape is almost certainly inadequate for an unbraced column 20 feet in length. Good Luck
 
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