Prediction of reinforcement corrosion due to chloride ingress and its effects on serviceability

Concrete is the most common man-made material in today's world. Embedded steel reinforcement may corrode due to chloride presence from de-icing salts or salt water, having impact on structural serviceability and life design. The paper presents a chemo-mechanical model covering initiation and propagation periods of chloride steel corrosion, taking into account concrete mix design, supplementary cementitious materials, concrete cover, crack width and environmental conditions. First, a short-term fracture-plastic constitutive model predicts cracking prior to the chloride ingress. Second, 1D model of chloride ingress yields the time of concrete cracking, spalling and the effective steel area. Third, mechanical analysis assesses the load-bearing capacity of a structure in dependence on the state of reinforcement corrosion. Validation includes two load-bearing structures loaded by chlorides; a concrete strut of a prestressed bridge in Prague, Czech Republic and Nougawa bridge, Japan.