connecting universal beams

lancenotalot · Posted: Tue Sep 08, 2009 7:08 am Post Subject: connecting universal beams

Hi guys and thanks for help so far,another question for you,is this an acceptable way to join the universal beams?

thanks

Deluks · Posted: Tue Sep 08, 2009 11:16 am Post Subject:

Should be fine. assuming that's a proper supporting wall and the end of the beams aren't doing anything funny.

I would hazard a guess at 8mm plate.

Ossy · Posted: Tue Sep 08, 2009 7:57 pm Post Subject:

Depends on how the UBs have been designed - continuous over the support or simply supported either side. If it's designed as continuous, this connection will need to resist a moment, which as shown it won't (well, not a very big one).

If it's simply supported (unlikely by the look of it), there's no reason to fix them together, as long as 50mm bearing is ok each end.

As it is, it's got a partial fixity, which a vigilant BC checker might pick up on and ask for the calcs to prove it, and the beams either side.

Best option might be to make one beam fly over the lintel support and then make a full bolted splice connection (with flange plates too) say 300mm away from it. Advantage of this is that the moment will be lower a short distance from the support (point of contraflexure).

Basically depends on how your calcs have been done.

^woody^ · Posted: Tue Sep 08, 2009 8:01 pm Post Subject:

Ossy wrote:

point of contraflexure

WTF!

Ossy · Posted: Tue Sep 08, 2009 8:07 pm Post Subject:

Thought that might be the response

Basically the point where the moment is zero - goes from hogging to sagging (just to complicate things further). And I spelled it wrong, it's contraflecture I think

^woody^ · Posted: Tue Sep 08, 2009 8:25 pm Post Subject:

I was concerned about that word before the 9 o'clock watershed. And no, the first spelling was correct

LOL .... move over shy, there's a new kid in town

Shytalkz · Posted: Wed Sep 09, 2009 1:14 pm Post Subject:

Yes, he's had his head stuck in his books and has got uber-complicated.

No one (in their right mind) will be doing continuous beam analysis for internal retrofit domestic situation beams. Unless they've fekked something up and it's already installed and they need to massage the numbers.

So, yes your detail will probably work, but if it was me, I would suggest sitting the longer span fully on wall, with 12 end plate. Other beam also has 12 end plate. 4M16 8.8 bolts connecting the two and 12 plates will eat anything domestic. No need for flange or web plates, or any fancy design and postulation about points of contraflexure.

Simple.

lancenotalot · Posted: Thu Sep 10, 2009 7:12 am Post Subject:

Spoken to the bco and structural engineer and they are happy with what has been suggested,initially the plates were to welded to one beam and bolted to the next but the have gone for this.

Thanks for all your help and suggestions,its to support the front face of a dormer extension,I have also had to put in beams across the center of the rooms to reduce the span of the existing loft beams so the can be used as floor joists due to limited head room (every inch counts you know

)