Probabilistic Evaluation System of Seismic Damage States for Bridge Structures
Akihiko KANEYOSHI , Ayaho MIYAMOTO , Hideaki NAKAMURA and Eiji NAKAYAMA
Abstract:This paper describes a newly developed probabilistic evaluation system of seismic damage states for bridge structures. At first, non-linear dynamic response analyses for the reinforced concrete bridge pier system were performed and the response values were calculated. And also, the probability of the first excursion for the threshold that corresponds to multiple damage states was calculated for each response value by the application of threshold-crossing in random vibration theory. Next, the damage transition probability matrix was constructed on the basis of probability of the first excursion. Then, the damage transition probability matrix conducted the damage transition model that included the damage interaction between elements. Finally, based on resulting probabilities of multiple damage states of structure elements, both functional and social damage states of the bridge structures damaged by earthquakes were evaluated. In addition, the development of a program for visualizing damage transition over time with graphical user interface made it possible to check the transition of structural damage easily in the behavior of the entire bridge structure during an earthquake. Then, by comparing cases with and without seismic retrofits, the effects of different seismic retrofit measures on seismic performance were evaluated. Key Words:Bridge structure, Seismic damage state, Evaluation system, Damage transition probability matrix, Functional damage, Social damage, Fault tree analysis