Back-to-back or Side-to-side Structural Members

[Jagpoe]

Hi,

When using back-to-back or side-to-side structural members, what would be the the behaviour/impact if I would not weld them together?
Any reference book/material which discusses this?

Thanks,

Jagpoe

 

[dik]

To have them act as a unit, you have to connect them for the shear load at the point in question.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[KootK]

When using back-to-back or side-to-side structural members, what would be the the behaviour/impact if I would not weld them together?

The impact would be that, for the majority of possible failure modes, you'd have to design this as two independent members sharing the load rather than as a true, built-up, composite member. As for references, any book covering the design of the individual pieces as single members would suffice.

Performance wise, you can expect massive differences in:

1) Axial capacity.

2) Torsional capacity.

3) Flexural capacity about the axis that would produce horizontal shearing on the mated surfaces.

 

[Ron247]

Loading also would matter. Hang a load from the bottom of the bottom member, and you get no assistance from the upper member. Similar for an axial load application.

Even farther in the weeds, manufacturing sweep and camber can be an issue. It they are not fully touching when a downward load is applied to the top member, the load will not be evenly supported by the 2 members.