Vibrating of concrete on metal deck 1

[midwestjt1002]

From what I interpreted, there's no where in the code that makes a distinction of vibrating of cast-in-place concrete slab vs concrete on metal deck. I'm aware that you need to vibrate cast-in-place, but for conc. on metal decks, is the use of a vibrating screed sufficient or would you require them to have a vibrator head inserted into the concrete itself? I've been in situations where contractors would and wouldn't vibrate the concrete and I'm not sure entirely if it's required...

 

[KootK]

Bump. I would also like to know the answer to this question. Perhaps it is a question that could be put to SDI.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[jayrod12]

I don't think I've ever seen concrete on deck being vibrated.

 

[hokie66]

Using vibrators on thin slabs is always an issue, metal deck or not. The only way you get some benefit is by laying the head flat in the concrete, but concreters tend to use the vibrator more to move the concrete than to compact, which in itself is terrible practice.

If a vibrating screed is being used, I would say that is sufficient. Most of the effective compactive effort in thin slabs is generally by gumboots and the screed, vibratory or manual.

 

[KootK]

Thanks for that hokie. Care to comment on when a slab become to thin to practically vibrate?

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[hokie66]

Slabs less than 150 thick...I think don't get good results with immersion vibrators, and rather need vibrating screeds. But when you get to 200 thick, the vibrating screeds don't compact to the bottom. The following is a useful reference.

http://www.boral.com.au/brochures/o...pdf?pdfName=DS2006-Compaction-of-Concrete.pdf