Optimizing Lifetime Condition and Reliability of Deteriorating Structures with Emphasis on Bridges

Abstract

Deterioration mechanisms of existing structures have been identified and studied over the last decades. Uncertainties associated with mechanical loadings and environmental stressors (e.g., chloride intrusion, freeze-thaw cycles) make it difficult to accurately predict the life-cycle performance of these structures. In general, deteriorating structures are maintained by periodical interventions based on their condition states. Available resources are limited and maintenance decisions resulting from management systems concentrating on condition states of deteriorating structures are not always cost effective. Therefore, the need for reliability-based structure management is evident. Models for time-based and performance-based (condition-based or reliability-based) maintenance strategies are applied in this study to a deteriorating bridge in Colorado. Several maintenance interventions are considered and combined. Realistic data consisting of condition, reliability, and cost of maintenance actions are used. Finally, the optimum maintenance strategy considering condition, reliability, and cost is selected based on different criteria.