Experimental and Analytical Seismic Assessment of Bents in Conventional Multi-Column Bridges

Recent earthquakes have shown that most bridges, which are usually designed using the latest version of seismic bridge codes, suffer different damages during the earthquake. Therefore, it can be expected that the designed concrete bridges based on the past design codes show inappropriate seismic performance under earthquake. Reinforced concrete bridges with non-integrated multi-column bents are one of the common types of the bridges in Iran. These bridges designed and built in accordance with old standard specifications have several defects in detailing which do not satisfy the provisions of the current seismic codes. So, it seems necessary to assess the seismic behavior of these common bridges. Experimental and analytical assessment of the behavior of bridge bents under seismic loading is the main goal of this study. To this end, a 25% scaled four-column bent is built which is consistent with the existing conventional bent represented bridges before 1990 in Iran. This specimen was tested under gravity and cyclic reversed loading for assessment the behavior of the bents. The results show that, unlike the specifications philosophy, the bent is damaged extensively out of plastic hinges region and capbeam joints controlled the seismic behavior of bent.

Keywords:

Seismic assessment , Multi-column , Bridge bents , Plastic hinge