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Re: Question regarding GLB

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Janelle:

This sounds like a radial-tension failure in the laminations. Although your 
beam is not a curved GLB, but it seems to have acted like one, possibly due 
to excessive deflection and curvature. You may want to look into 
repairing/reinforcing the beam with thru bolts or rods. After shoring the 
beam, drill through holes top to bottom, install bolts or rods, inject 
laminations with adhesive, jack the beam up, then tighten the bolts. Let the 
adhesive cure then release the beam.

This is how I would do it.

Regards,

Oshin Tosounian, S.E.


-----Original Message-----
  From: JANELLE L. PERRY [mailto:jlp(--nospam--at)schneiderassoc.com]
  Sent: Wednesday, December 08, 1999 2:25 PM
  To: seaint(--nospam--at)seaint.org
  Subject: Question regarding GLB


 I have been asked to design a repair for a Glue-Lam beam approx. 20-30
  years old.

  The beam seems to have failed in tension at a finger-joint in the =
bottom
  lamination and delaminated up from the failure 3' and above the =
failure
  at the center of the beam. (or vice versa, I suppose).

  The beam is in an exposed condition, which makes the fix more =
difficult.
  It is a 5 1/8" x 18" beam spanning 30' with the failure occurring =
about
  10' from the face of support.  The beam holds about 15' of tributary
  tile roof, sloped at approx. 4:12.

  I would appreciate any help or guidance.

  Thanks.

  Janelle