It will be advantages in lowering Rapid Chloride Permeability Test (RCPT) and minimising Alkali Silica Reaction (ASR) risk.
In fact, triple blends (OPC / GGBS / Fly Ash) performs better than either the OPC/Fly Ash and OPC/GGBS blends but there will be logistic and handling/storage problems.
Sometimes, we may will likely need to use silica fume in Mix Design to achieve better RCPT.
The calculated total alkali (expressed as Na2O equivalent) in most of the cement plant are:-
1) OPC ~ 0.35
2) GGBS ~ 0.31
Please be informed that Singapore Building & Construction Authority (BCA) requirements of <0.60.
Cement supplier in Malaysia, usually do not get into details of Mix Designs and leave to experts like Admixture suppliers whom can liaise with for trial mix at their lab or customer site.
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