How do we ensure a raj does not move sidewards

[mrbg07546]

A few months ago we put a rsj in for a door opening. It passed building control. I always wondered what supports it from not moving side wards other than the downwards force and the plasterboard

 

[tomfe]

Well is should be level at across the beam(tangent to span) so where is the force which is going to push it out sideways?

 

[^woody^]

Unless it's on wheels with the handbrake off, it won't move sideways.

See Newton's first law.

 

[John D v2.0]

Most of your house is held in place with gravity, that included. It should be on a flat surface with basically a downward force on it.
Although if your lintel is long enough, you have to worry about whether the bending forces will cause the top edge to move sideways and around the bottom (ie a twist in the middle) but the structural calculation should conform that's not an issue.

 

[mrbg07546]

The question came about because one of the builders I had was hammering the noggings into the the rsj. And it deflated slightly right. I stopped him immediately. But just got me thinking