Tension in glulam beam perpendicular to grain 2

[nivoo_boss]

Hey everyone!

Is there some way to estimate the capacity of the joint seen on the drawing below? A force is applied to the notch, which puts the area near the cut in tension perpendicular to grain.

 

[ChorasDen]

No. Assume capacity of 0psi. AITC and APA have documents discussing why this is a bad idea.

 

[phamENG]

While the capacity is, in reality, not 0psi, the actual value is too low and variable to be of any reliable use to an engineer.

If you're looking at individual pieces of lumber, the Truss Plate Institute has some information (because light frame, pre-fab trusses rely on tension perpendicular to the grain in essentially every connection). But even then those values are low enough to be useless in any other application, and glulams are a big no always.

 

[nivoo_boss]

EC5 section 6.5.2 seems to deal with this type of joint. Seems to use reduced shear capacity.

 

[SWComposites]

The notch will introduce a horizontal crack. There is no "stress" based procedure to calculate a "strength"; one would have to use some sort of fracture mechanics approach to predict crack onset and propagation, which would entail somehow getting fracture toughness values for the wood material, which is a research project ...............

 

[bugbus]

Can’t you reinforce this with some big screws?

 

[Agent666]

There's a few methods in this document, very easy to strengthen with a few vertical screws.

https://engineervsheep.com