double wood beam - shear control? 4

[mats12]

Hi, maybe that is a silly question but its not my area...

Lets say we have a roof wood beam (element 1), but its not sufficient on its own (shear forces too big) so we add another wood beam (same material) on top of it (element 2).

Can I consider this now as one element when making control for shear forces? Does there have to be connection?

I know it has to be connected when dealing with bending (shear flow between elements so we need bolts or other connectors) but what if I know that element 1 is Ok as far as bending goes on its own? Because of that i really want to avoid calculating shear flow and bolts and calculating effective moment of inertia Ieff - because of a slipping between elements, etc.(according to eurocode 5).

BTW i have to connect elements somehow so bolts should be OK?

 

[molibden]

Heldbaum, that is what I would do with self-tapping screws - full thread. Besides gluing that is the most rigid connection, because you rely on screws in tension and not shear.

Also you could do this (tension+compression): Picture