Bolt in wood joint, minimum anchorage length?

[HEA260]

Hello,

I want to join 3 pieces of 45x170mm with a bolt (M10/M8) + nut. So it will be a double-shear connection. I am wondering if there is a minimum anchorage length for bolts in wood?

Best regards

 

[prototypen]

Is it the distance from the screw hole to the end of the plank that you're wondering about?
You write two-cutter joint and I interpret that as the outer planks are going in one direction and the one in the middle in the other direction.

Protte

 

[Ahmada]

Is it the distance from the screw hole to the end of the plank that you are wondering about?
You write two-cutter connection, and I interpret that as the outer planks strive in one direction and the one in the middle in another direction.

Protte

It's not the distance to the edge I'm wondering about, but if there is a minimum anchorage length (t2) that must be met for a bolt. In this case, t2=45mm. And the question is whether this is enough?

If it had been a smooth nail, for example, the anchorage length would have needed to be at least 8d.

 

[Workingclasshero]

What is "tvåskärigt förband" and what is anchorage length?

 

[Ahmada]

What is "tvåskärigt förband" and what is anchorage length?

See the image below, where a) is single-cut and b) is double-cut. The anchorage length in this case is what is referred to as t2 in figure b) below.

 

[fahlis]

Now you write that the parts should be joined with bolts and nuts. Then it will be a through bolt and the question of anchoring length will not be applicable...

 

[Ahmada]

Now you write that the parts are to be joined with bolts and nuts. Then it will be a through bolt and the question of anchoring length does not apply...

I understand, so is 45mm enough on the wood in the middle for, say, an M8 bolt?

 

[Tomture61]

It is also important with the dimension of the screws, number, placement.

 

[Ahmada]

It is also important with the dimension of the screws, number, placement.

See attachment, the bolts are M8/M10 (strength class 8.8).

 

[Tomture61]

See attachment, the bolts are M8/M10 (strength class 8.8).

What are you fastening? Roof truss?
A hole for a screw (bolt) cuts through the wood fibers quite effectively, unlike nails.
Nail plates are even better, but that doesn't work in your case.

 

[Ahmada]

What are you joining? Truss?
A hole for a screw (bolt) cuts the wood fibers quite a bit, a nail doesn't do that in the same way.

Yes, truss, 2 on each side attached to the existing truss. So would you recommend nails instead?

 

[Tomture61]

Yes takstol, 2 på vardera sida fästs mot befintliga takstolen. Så du skulle rekommendera spikar istället?

Absolutely, 100%
There are instructions for how many nails and where, unfortunately I can't find it right now.

 

[Leif i Skåne]

Use construction screw. Type ET-T
I screwed up all glulam beams up to 420x 115 mm with that screw.
https://www.essve.com/sv/essve-guider/skruv-guider/proffsguide-et-t/Introduktion/

 

[bossespecial]

What is the reason for nailing to 2 new studs?

 

[Ahmada]

Absolutely, 100% There are instructions for how many nails and where, unfortunately, I can't find it right now.

I will calculate it.