Developing Performance Levels for Concrete Bridge Bents with a Focus on the Joint Region

Bridges are critical highway structures, and damage to them can result in the loss of vital lifelines. Many bridges reaching the end of their expected lifespans should have their seismic performance evaluated immediately. The study utilized a 1/3 scale model of two-column bridge bents developed within the last 20 years that split from the deck under cyclic loads. The purpose is to investigate seismic performance and define performance levels utilizing experimental observation. The damage estimates from previous studies for each performance level were reviewed and, where necessary, revised. Damage and performance levels for joints were estimated differently than for other components such as cap beams and columns, according to the findings. The present study proposes new performance levels including joint damage. The overall seismic performance of the concrete bridge bents revealed that the anticipated mechanisms did not occur, but that flexural hinges formed in the joint region rather than in the columns, as required by current codes.