MAINTAINING RELIABILITY OF CONCRETE STRUCTURES .1. ROLE OF INSPECTIONREPAIR

This is the first of two papers that describe the role of in-service i nspection/repair in maintaining the reliability of Concrete structures during a projected service period taking into account the randomness in existing damage and in damage detection. The degradation in strengt h of a component due to environmentally aggressive factors is evaluate d based on a growth model for individual random damage that can be obt ained from experimental data. The distribution function of damage inte nsity after an inspection and repair is updated using a Bayesian analy sis. This methodology can be used to determine inspection/repair strat egies that are necessary to keep the failure probability of a concrete structure at or below an established target. Sensitivity analysis sho ws that the variance in the function describing degradation in strengt h is small even if the variance of individual damage intensities is la rge. However, the degradation function is sensitive to the threshold o f damage detection of the nondestructive evaluation (NDE) method selec ted for in-service inspection.