Probabilistic-Based Safety Evaluation of Maryland Sign Structure System Subjected to Wind Effects

Performance assessment is important for existing infrastructures because it can effectively help conduct maintenance and keep the structure in good condition. In this study, with the database of sign structures provided by the Maryland State Highway Administration (MDSHA), a probabilistic-based analysis approach, with reliability concept, is developed for the assessment of sign structures for the state of Maryland. This approach uses structural members’ combined stress ratio (CSR) and fatigue stress ranges based on a standard specification as failure criteria. In existing sign structures, the focus is on Type CN2 (planar cantilever sign support), which is the category with the largest proportion of fatigue galloping-sensitive cantilever structures, and Type OH6 (box truss overhead sign support), which is the category with the largest proportion of overhead structures. Eventually, the failure probabilities of CN2 and OH6 groups are obtained, indicating which portion of sign structure is at high risk. Results of this study on sign structures will provide a basis for future inspection and maintenance of the infrastructure system.