Modeling study reveals that equivalent-aperture calculations overpredict contaminant ingress at concrete construction joints, suggesting their current role is limited to screening.
Key Points
Evaluate an analytical framework that converts measured gas permeability into an equivalent hydraulic aperture to model gas diffusion, carbonation, and chloride transport at concrete construction joints.
Converted measured gas permeability to an inverse-derived equivalent hydraulic aperture to model gas transport, carbon dioxide diffusion, and chloride ingress across construction joints.
Calculated an empirical model-to-measurement ratio (β) to compare theoretical transport depths against controlled laboratory concrete specimens.
Performed scenario-based service-life assessments on fly-ash concrete using Monte Carlo propagation of aggregate permeability scatter.
Calculations systematically overpredicted both measured carbonation depths and chloride penetration depths in jointed laboratory specimens under the tested conditions.
Joint conditions shifted the projected balance between carbonation and chloride penetration in fly-ash concrete, though results represent conditional screening comparisons rather than proven design bounds due to uncalibrated porosity and tortuosity parameters.