Time-dependent reliability of deteriorating reinforced concrete bridge decks

A structural deterioration reliability model is developed to calculate probabilities of structural failure (flexure) for a typical reinforced concrete continuous slab bridge. Corrosion may be initiated from the application of de-icing salts or atmospheric exposure in a marine environment. It is assumed that corrosion will lead to a reduction in the cross-sectional area of the reinforcing steel. Monte Carlo simulation is used to calculate probabilities of failure for annual increments over the lifetime of the structure (75 years). The application of de-icing salts or atmospheric marine exposure is shown to cause significant long-term deterioration and reduction in structural safety. Reducing the cover from that currently specified for design results in a significant increase in failure probabilities.