where kC3S is the dissolution rate constant at infinite dilution, approximated
from the experimental data as 125.3 μmol m−2 s−1, Aeff is the
C3S surface area on which C–S–H growth can happen, which may be
less than the actual C3S surface area due to coverage by existing hydration
product, and C1 and r are constants determined by fitting Eq. (2) to
the data by a least-squares method. The C3S dissolution reaction
assumed in ref. [4] is