Seismic behavior evaluation of performance and damage index in bridge pier concrete bent with seismic detail defection

Bridges are considered as important structures in the essential arteries of life. In recent earthquakes, the necessity to retrofit the structure of bridges has become apparent as an undeniable truth. In Iran and in recent decades, the engineering community has been trying to adapt itself to the regulations of the world. In the 1990s and early 2000s in Iran, the behavior of bridges has been considered under gravity loads more than their seismic behavior. Most of the bridges being used lacked the appropriate standard administrations for preserving the earthquake functions. To this end, the current study has focused on the evaluation of concrete frames ‘behavior of high-ways' common bridges in Iran. Accordingly, two types of concrete frames with the existing details according to the average of several bridges having different pier numbers under the lateral loading, have been investigated. Moreover, the knee and mid joints' behavior have been compared step by step. The performance evaluation of these bents illustrated the need for seismic improvement for desirable Failure mode, and the process of damages and performance levels of components had shown an unsuitable failure mechanism. Also, the quantitative values of indices of damage have been studied separately, which can be used in future studies.