Early Thermal Cracking

[TPWells]

Hi,

I am designed a concrete basin for a cooling tower which is 20m x 10m in plan dimension. The base is made up of a 500mm thick slab sat on a number of ground beams on piles. In the design of the base slab I have allowed for early thermal cracking as per BS 8007 and due to the piles have included an end restraint factor of 0.5 [which is assuming the slab is restrained at each end]. At the moment I am tying in the pile caps to the base slab with rebar. As per BS 8007 it says I have to take into account the restraining factor of the piles. Would using a 0.5 restraining factor be adequate to take this into account?

Thanks,

Tim

 

[BAretired]

Who knows? It depends on the dimensions of the pile and the properties of the soil. In addition to thermal cracking, you can expect shrinkage cracking.

BA

 

[hokie66]

BA,
The Brits tend to commingle thermal cracking and drying shrinkage cracking under the one banner of "early thermal cracking".

TPWells,
I haven't used the BS standard in a while, but if you are assuming the slab is restrained at each end, it sounds like you are doing the right thing. What percentage of steel are you getting based on the gross area of the slab?