Wooden floor beam

[BAGW]

Hi,

I was looking at some wooden beams for redoing the floor online. I see this crack sort of thing in all the beams supporting the floor. what are those? That cannot be the crack in the beams due to beam overstress. I see that on all beams. Trying to understand what those are.

when I shop for new beams, I see that in the new beams as well. Is it to accommodate thermal expansion?

Thanks

 

[r13]

I think better interlocking should gain some strength, but not enough for other considerations.

 

[KootK]

This would suggest that web splice joints do not achieve the full strength of the unspliced web.

 

[r13]

Yeah, the problem is the limit length of OSB available.

 

[Tomfh]

This would suggest that web splice joints do not achieve the full strength of the unspliced web.

Makes sense that it's a weak point. You can see it in that failure video above.

It's impressive that the finger jointed flange splices can exceed the strength of unspliced material. Here's a pic of joist with finger jointed flanges and butted webs:

So presumably you can get full bending capacity, LESS the web bending capacity. And with the reduced shear capacity you get failure like the video above.

 

[r13]

It reminds me the risk of modifying/strengthening the existing joist without knowing its weakness. Better not to mess with structures rated by tests rather than calculations using engineering theories.