The exposure time at which a threshold Cl- concentration, Ct, is initially achieved at the
reinforcement depth in concrete such that passivity is compromised and active corrosion initiates, Ti, is an
important service life determinant for reinforced concrete structures. Composite component of concrete
materials results in no consensus in the literature of a value for Ct, as reported concentrations extend over
one order of magnitude, which was contributed to multi-parameter interaction. However, there is; and it
has become increasingly apparent that Ct is distributed even for apparently identical specimens. In a
companion paper, models for randomly arranged non-diffusive coarse aggregate (CA) particles in
concrete cover were generated for different aggregate types (particle size and size distribution), CA cover
depth, the ratio of chloride threshold to surface chloride and the effect of these factors on the corrosion
initiation of reinforcing steel was investigated as a function of Ct by finite element analysis. In the present
work, the effect of CA with finite diffusivity on corrosion initiation is addressed and the results are
discussed with those presented in previous paper. Discussion within the context of understanding factors
that affect the relatively wide variation in Ct that has been reported in the experimental and modeling
literature is also involved.
Keywords: concrete, reinforcing steel, corrosion, chlorides, finite diffusivity, coarse aggregate; modeling
analysis.