Glu-Lam beams delaminating
Glu-Lam beams delaminating
(OP)
I was asked to look that the roof beams of a structure built in the early 1960's which has Glulam beams @ 11' oc and 3" cardecking. The glulams did not have finger joints at the ends of the individual boards and at several locations the bottom ply was splitting off along the glue joint from the butt ends of the bottom board. I have attached a photo.
Have any of you ever seen glulams made this way?
Have any of you ever seen glulams made this way?






RE: Glu-Lam beams delaminating
[Added] Glulam at that time was graded so that stronger material was on the outer fibres of the beam and typical strength was 2400 psi in flexural tension.
Dik
RE: Glu-Lam beams delaminating
TTFN (ta ta for now)
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RE: Glu-Lam beams delaminating
My friend asked what the options are. I told him the best bet was to figure on at a minimum, removing and replacing all roof structure or look for another property.
RE: Glu-Lam beams delaminating
RE: Glu-Lam beams delaminating
This can be repaired in place. Is the roof constructed using 3" T&G Plank? The glulam can be jacked up a bit to make it more level.
Dik
RE: Glu-Lam beams delaminating
In the 60's, before finger joints, a lot of glulam were made with "scarf joints" and casein (Elmer's) glue.
I've seen a lot of glulam with separated scarf joints and some with failed joints - due to casein in wet or humid locations.
You could sandwich with steel each side or even glulams of LVL's.
RE: Glu-Lam beams delaminating
Of course, you want to shore the beams or the roof structure during the repair, to take much of the load off the beams during the repair. Otherwise, the beam will have to open up even more and deflect more before the bottom reinf. pls. even come into play and start to pick up a share of the loading, or tension loads in the bot. plys. You would also like to stress/stretch any splice pls., to get any slack out of the and out of the bolt or nail holes, so these don’t have to be taken up before the pls. start to pick up their share of the loads. You could also post tension the beams with harped rods on either side of each beam. The rods would have turnbuckles, a saddle of some sort at center span, and a pl. or channel or some such across each end for the dead end of the rods.
RE: Glu-Lam beams delaminating
TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm
RE: Glu-Lam beams delaminating
RE: Glu-Lam beams delaminating
Dik
RE: Glu-Lam beams delaminating
RE: Glu-Lam beams delaminating
An early 60s structure possibly had a cedar shake roof, which comes in at about 0.5 lb/sqft, dry. If the roof was subsequently converted to cementitious roofing, ala EagleLite, it'll come in at least 5.5 lb/sqft. For a 2500 sqft roof area, that's an additional 6.25 tons of roof loading.
TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm
RE: Glu-Lam beams delaminating
Dik
RE: Glu-Lam beams delaminating
RE: Glu-Lam beams delaminating