Masonry Deflection for Long Horizontal Spans

[Encoeng]

Our office is working on a number of banks that have teller drive-thrus with 2 to 4 feet of masonry veneer. On some of the jobs, the spans for the supporting beams are 50 feet long. If we size these beams for L/600, we get a huge member that seems excessive. Is there a differnet guideline to follow for this situation, or do we need to use the L/600 tolerance?

 

[DaveAtkins]

You could put vertical soft joints in the brick every so often. Just make sure you figure out how much these joints will compress at the top, so that you can specify the correct joint width and sealant.

DaveAtkins

 

[ahunt]

It seems a little worse than L/600. ACI 530 states a maximum deflection of 0.3" or L/600, whichever is less.

I heard an ACI speaker once say the 0.3" was added after complaints had been made that on long spans you can see the vertical displacement too much. Not that it cracks the masonry.

Sounds like you need more supports.