Maintaining Reliability of Concrete Structures. II: Optimum Inspection/Repair

Abstract

This is the second of two papers that describe the role of in‐service inspection/repair in maintaining the reliability of concrete structures taking into account the randomness of existing damage and damage detection. Since inspection and maintenance are costly, there are trade‐offs between the extent and accuracy of inspection, required level of reliability, and cost. The method to evaluate degradation in strength of a component described in part 1 is combined with the time‐dependent reliability analysis to devise optimum strategies for inspection and maintenance that minimize the expected future cost of structures and components, while maintaining their limit‐state probabilities at or below an established target failure probability. Optimum inspection/repair strategies are sensitive to the relative costs of inspection, repair, and failure as well as to the threshold value of damage detection. Inspection at approximately uniform intervals leads to near minimum costs for a wide variety of cases studied.