Probability Analysis of Corrosion Process of Corroded RC Flexural Member in Marine Environment

摘要

The main cause of deterioration in reinforced concrete (RC) structures is related to reinforcing steel corrosion, therefore, the calculation of steel corrosion loss should be evaluated in detail. The corrosion initiation time and concrete cracking time are random variables due to the various uncertainties in reinforcement corrosion process. Thus, RC structural member at a specific observation time of design period may be in three different states, namely no corrosion, ongoing corrosion but no cover concrete cracking, concrete cover cracking. Accordingly, a probabilistic model for corrosion loss of steel cross-section was developed in three critical phases. For illustrative purpose, statistic analysis of the percentage of corrosion was conducted using Monte Carlo simulation for a simply supported RC flexural member, in which the occurrence probabilities of above three different states at an observation time were determined. The statistical results showed that percentage of corrosion can be described by a double-peak probability distribution; the occurrence probabilities of no corrosion and no concrete cracking decrease with time; the reliability of RC flexural element in marine environment significantly decreases with time due to reinforcement corrosion.