SEISMIC BEHAVIOR OF MULTI-CFT COLUMN BRIDGE PIERS WITH SHEAR DAMPERS IN TWO-SPAN ELEVATED-GIRDER BRIDGES TESTED BY SHAKE-TABLE EXCITATIONS

Abstract

 Under the Level 2 earthquakes, the respective CFT columns of the multi-column piers are designed to be almost free from damages by the energy dissipation of the shear panel dampers installed between the columns. To examine the seismic performance of these piers under severe earthquake motions including those that exceed the Level 2 earthquakes, bi-directional shake-table tests were carried on a 1/10 continuous elevated-girder bridge model with rigidly connected multi-column piers. As a result, it was confirmed that the CFT columns of the piers were almost free from damage under the Level 2 earthquakes. Under the more severe earthquakes, the piers exhibited an excellent seismic performance by the energy dissipation of the CFT columns. Based on the results of the shake table test, modelling of the multi-CFT column piers were also discussed in view of the application to the seismic design analysis.