split slab concrete parking deck

[mck26]

I have a split slab parking deck project in northern climate. It is a steel framed floor with a reinforced concrete slab. A waterproof membrane was adhered to the slab then protected by a protection board and a 3" concrete surface topping. The topping has caulked saw cut joints at 7' on center each way. The entire system slopes at 1/4" per foot to multi level drains. The construction is 7 years old. The concrete topping is cracking all over and spalling. The topping has observed cracking days after initial placement. The argument is that a drainage board was not specified or provided. We have multiple parking deck projects in northern climates that are much older without showing concrete topping damage. Does anyone have parking projects that utilized this type of system successfully (split slab with membrane, without drainage board)? Is there any national standards or research that I can reference?
Thanks

 

[dik]

What type of protection board? if soft, then 3" topping may crack due to displacement.

May have been further ahead using a membrane and traffic surface...

Dik

 

[mck26]

No, it was a hard protection board.

 

[a7x1984]

Photos of the deck would be helpful. Might be a bad mix.

In Russia building design you!

 

[MJB315]

Was the topping reinforced?

"We shape our buildings, thereafter they shape us." -WSC

 

[mck26]

Sorry, no pictures.
No the topping was not reinforced.

 

[a7x1984]

Not even for T&S?

In Russia building design you!

 

[dik]

Any idea of the concrete mix design, strength, slump, etc?

Dik

 

[mck26]

Temperature and shrinkage cracks were controlled by the 7'x7' sawcut grid.
Concrete was a normal 3000psi air entrained mix with standard slump and normal weight aggregate.

 

[dik]

Standard slump may be too high and 3000 psi is too low... 7'x7' panels for 3" concrete with wheel loads may be a tad too large, in particular, on driving isles...

Dik

 

[briancpotter]

How long after placement was the sawcutting done?

Brian C Potter

http://simplesupports.wordpress.com

 

[dcarr82775]

3ksi is too low in my opinion, especially for a northern freeze/thaw climate with auto traffic.

 

[briancpotter]

If the slabs are cracking days after initial placement (presumably before they're being driven on), it strikes me as unlikely it's a climate or traffic issue causing it (though I agree 3ksi might be too low).

Brian C Potter

http://simplesupports.wordpress.com

 

[dik]

Any idea of the placing conditions? Hot, cold, calm, windy, clear, cloudy, etc. All may have a bearing on outcome...

Dik