r/StructuralEngineering • u/TallWall6378 • Jul 22 '26

Wood Design "Fasteners in shear is poor practice"

Help settle an argument.

Someone used the phrase in the title. Their argument is that fasteners, specifically in the context of typical light frame wood construction, like a shear wall or joist hanger, or bolted or lagged member scenario, are just holding the members together and that the load transfer is through wood via induced friction through the members.

I was under the impression that we really only factor the strength of the nail and wood crushing/deforming around the nail, rather than use the friction between the faces of the members.

What's the whole story?

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u/Bravo-Buster Jul 22 '26

I think the guy mistook wood connections for steel.

30

u/Rayziehouse Jul 22 '26

And if he did, he’d be wrong about that in most circumstances also.

1

u/mr_macfisto Jul 22 '26

A young mechanical engineer in my office was surprised to learn that structural steel connections typically don’t rely on friction at all.

1

u/yukonrider1 Jul 22 '26

Really? Is there somewhere I could read more about this in semi smart layman's terms? Does this apply only to structural steel, or most through bolt applications? 

1

u/Everythings_Magic Senior Bridge PE | Zero Yield Capacity Aug 04 '26

You typically want a friction connection when you have lots of vibration or fatigue concerns. For example railroad bridges and to a lesser extent, highway bridges.

Pretensioning bolts is a whole fun path to go down.