SEISMIC VULNERABILITY OF HIGHWAY BRIDGES IN ISTANBUL
(Thesis Supervisor: Özal Yüzügüllü)
Highway Bridges are of primary importance both during and immediately following an earthquake. From this point of view, evaluating the seismic reactions and vulnerability of available highway bridges in an important earthquake; predetermining the precautions required to be taken against the damages before the earthquake and retrofitting have a vital importance. Seismic vulnerability of a bridge can be defined as the potential of a bridge to sustain sibmificant damage or collapse. Investigation of above topics on Istanbul requires paying more attention since it is one of the greatest inetropolises of the world with two suspended bridges and lots of important viaducts. Therefore, the goal of this study will be to evaluate the seismic vulnerability of underpasses, overpasses and viaducts lying on; 01 and 02 highways connecting Istanbul to Europe and to Asia, and the link lines connecting these highways to each other in case of a probable major earthquake in Istanbul. As a result of this purpose, preliminary screening has been applied to all 51 bridges and vulnerability of all these bridges has been obtained. The results of the numerical ratings of preliminary screening have given an idea about the individual components of the bridges according to ATC-6-2 method by excluding any detailed analysis. According to preliminary screening results, it can be easily seen which bridges a detailed analysis should be applied to. In this study, a detailed analysis has been applied to viaduct V409, since it is an old and relatively big viaduct.