Hello!

My dad and I ended up in a discussion about glulam beams and strength/load-bearing capacity. For example, a 56*225*6000.

Dad claimed that it didn't matter if you placed the glulam beam "flat" on its side so it becomes only 56mm high and 225mm wide, or if you stood it up on its edge 56mm wide and 225mm high.

I argue that of course it doesn't work like that and tried to reason with common sense. Obviously, a lying beam won't be as strong as a standing one because the laminates are placed next to each other. But he didn't buy it because it was "industrially created."

So, assuming I'm right with my common sense, I've tried to find detailed information in the wood guide. Preferably to be able to calculate and show. However, I can't find where there might be information about lying beams. For poles, there is buckling load in, for example, x or y direction.

Is there any reference on the strength of a lying glulam beam?
 
Google the bending resistance of beams. The old man is wrong.
 
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Deek
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For each doubling of the height, the load-bearing capacity quadruples.
The load-bearing capacity is quadratic with the change in height.

Assume a hypothetical material with the dimensions 100x400 mm
Divide into 100x100 mm pieces.
Each piece has a load-bearing capacity of 100
With 4 pieces in width, the load-bearing capacity is 400
With 4 pieces (strongly joined) in height, meaning 4 times higher, gives a load-bearing capacity of 4*4*100=1600

With the beam on its edge, it became 4 times stiffer.
I noticed this past summer when I ran on scaffolding planks, 45*220 flexes quite a bit, but then as rafters on their edge, it became significantly sturdier.

Your father-in-law might have a point; factory-made with thin laminates and knots here and there is stronger than solid wood that may come with continuous knots.
Protte
 
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SC Aero and 2 others
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The prototype above is absolutely correct.
But you are also completely correct in saying that the lamellas are positioned right/wrong.
When laid horizontally, the beam is not much stiffer than regular wood.
When standing upright, the factor for errors and defects is eliminated, making glulam more than twice as strong.
 
Try with a regular board between two supports. Is it as easy to bend standing on edge as when it's lying down?
 
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