Sulphate Resistant Concrete

[tclat]

Dear All,

I'm looking for an alternative to using Type V cement on a project. The soluble sulphates are as high as 1.9% and chlorides vary between 8-22%.

I've looked at various waterproofing additives but they tend to make very generalized statements about "improved chemical resistance".

Another option is the use of Silica Fume but again from my research I am only able to get general comments.

Has anyone had any success using an alternative and or details for using silica fume?

Thanks

 

[cliff234]

I am not an expert at this, but about replacing some of the cement with slag? The lower the content of Tricalcium Aluminate (C3A) and Sulfur Trioxide (SO3) in the cement (using Type II and Type V cement), the lower the expansion will be when sulfate ions get into the concrete. Using less cement (replacing it with slag) is another way of reducing the C3A and SO3.

 

[dik]

We often use 25% or so flyash with normal PCC for sulphate and chloride resistance, subject to flyash history for resistance.

The use of sulphate resistant concrete with chloride attack is generally contraindicated.

Dik