Steel Joist failing shear remedy

[maneesha0702]

I am checking a 28k10 joist for additional loads. However the joist is failing in shear. What is the best remedial measures that should be adopted? I am enclosing the joist calculations for reference. Any help is appreciated.

 

[Triangled]

didn't see attachment, but absent some unusual circumstance,
a) distribute loads to adjacent joists
or
b) reinforce for shear

 

[KootK]

Is the over stress in the webs or the seat?

Here are some starter ideas along the same lines as triangled's suggestions: Link

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[JedClampett]

It is unusual for a beam of any type to be overstressed in shear. It must be a honking big load. Or very close to the end. I'd also be worried about the end connection, plus the supporting member.
I'd feel better replacing the member with something a little stouter, like a wide flange. Any chance of that working out? We shouldn't, as structural engineers, jump through hoops to make an inadequate member (put in to save some bucks, even if it was long ago) adequate. Someone made a financial choice, and now they or their heirs will pay the price.

 

[msquared48]

Sometimes you can add another angle or smooth rod to the web members that are failing.

If you know the joist manufacturer from the tag, you might call them for a fix if they are still in business.

Mike McCann, PE, SE (WA)

 

[Triangled]

def try the joist tag route as when it is successful, it's great. hope it doesn't work out for you like mine last week..."yea that joist tag is for ABC. They of course went out of business and were bought by XYZ. By the way, XYZ went out of business and was bought by us a few years ago. From the tag number there is a decent chance we'll have some data. $1000 non refundable to look for data. By the way we can't start looking until after the 1st of next month because we're so busy. We do accept credit cards though...."

 

[KootK]

My fave: "Oh yeah, we remember that. However, we get a beak from our insurer if we delete our records for anything over ten years old."

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[Triangled]

that's a good one

 

[JAE]

maneesha0702,

You can try here: Get SJI to help you

Or here: SJI Technical Digest No. 12 Evaluation and Modification of Open Web Steel Joists and Joist Girders


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[SteelPE]

Depending on the over stress and the field conditions you could add another spliced joist in-between the existing joists. This works out well if you have little in the way (ie no sprinklers).

Another option, depending on the location (as in on a roof), is to put a new frame system above the joists to support the new load. This system could be rigged to run from girder to girder (if adequate) or from column to column.

Another thing we would also do, if allowed, is to move the load to a location where there is no longer an overs stress.