vierendeel trusses

[Lion06]

I have a very interesting project coming up that will require the use of VERY LARGE vierendeel trusses. I have looked through my steel texts, and my structural analysis texts, but can't find any information on them. Does anyone know of a good reference for me to read up on this - just to get myself acquainted with this topic?

 

[jike]

"Design of Welded Structures" by by Blodgett available from Linclon Arc Welding.

 

[Lion06]

Ah, the one book on my shelf I didn't think to look.
I will check it out!
Thanks!

 

[COEngineeer]

Yeah.. I agree with jike.. its not even trusses. Its all fixed. A lot of welding for sure.

Never, but never question engineer's judgement

 

[PEinc]

Omer W. Blodgett's Design of Welded Structures discusses Welded Connections for Vierendeel Trusses in Section 5.13, Pages 5.13-1 to 8.

 

[PEinc]

Wow, you people are too fast for me!

 

[csd72]

They are just basically 2 multi storey portal frames back to back, the analysis is similar.

Note that the deflection of a vierendeel is much higher than a normal truss of similar size and members. First time I did one I was surprised how much more.

csd

 

[JAE]

I've found StructuralEIT and COEngineeer to be "like lightining". Always suspected them of Flash Gordon tendencies. I bet their projects are always on time too!!

)

 

[SlideRuleEra]

thread507-85066

http://www.SlideRuleEra.net

 

[Lion06]

JAE-
That went over my head. Was that a dig?

 

[msquared48]

Obviously. If that went over your head, you're already in the hole....

Seriously though, the reason that Vierendeel trusses are plagued with so much more deflection is that shear contributes to the deflection to a much greater extent than with "normal" trusses with diagonals.

Mike McCann
McCann Engineering

 

[WillisV]

A Vierendeel truss is just a moment frame turned sideways...just like a braced frame is just a typical truss turned sideways...

 

[PEinc]

An engineering firm I know designed a temporary Vierendeel truss after I recommended that they rent an Acrow panel truss. They said that the Acrow rental cost would have been too high. So, the Vierendeel truss was specially fabricated but buckled as soon as they tried to lift one end. They then had to repair and reinforce the truss. A Vierendeel truss would not be my first chouce. The joints are much more complicated due to their requirement to resist moments. The design probably costs more than a more common truss. The fabrication is probably also more expensive. You will pay a higher price for a sleeker looking truss.

 

[nutte]

Blodgett has everything. I find myself looking their first on a lot of issues.

 

[csd72]

Is there anything thats not covered by blodgett or Roarks!

 

[DaveVikingPE]

How do you pronounce "Vierendeel"?

I've heard it said "veeeer - en - deal"
And I've heard it said "Vie - Ren - De - El"

I like the latter, but I would like to be correct.

"Is there anything thats not covered by blodgett or Roarks!" I don't know about Blodgett, because there's no index at the back of his books.

 

[JAE]

Not a dig...just an awkward compliment - recent months you two have seemed to pounce on posts quite well.

 

[bridgebuster]

I've always heard it pronounced "veeeer - en - deal" - New York French.

"there's no index at the back of his books" - that's how he keeps the prices reasonable.

 

[lkjh345]

In the FWIW catagory:

I would be cautious about spending a whole lot of time studing the intricate details of a vierendeel truss at this time.

A lot of architects like to show them in the Concept Design stages becasue they look great. Quite a few get replaced by conventional trusses during the design (or construction) stage after the contractor tells the owner how much the vierendeel will cost.

Have shot myself (and my budget)in the foot a couple of times this way. Have gotten wiser to the game over the years.

 

[COEngineeer]

I thought they use these trusses so you can put windows and stuff? I dont think you can use diagonal member. The architect wouldnt allow it i bet.

Never, but never question engineer's judgement