Seismic Assessment of MacArthur Bridge in Manila Using Pushover Analysis and Capacity-Spectrum Method

The Philippines is situated at the Pacific Ring of Fire and is known for being the focal point of active volcanoes on both land and water, making it susceptible to earthquakes and tsunamis that cause threat to infrastructure. One of the most vulnerable structures are public bridges, specifically the MacArthur Bridge in Manila. The study focuses on analyzing the seismic vulnerability of MacArthur Bridge when subjected to 15 local and international high magnitude earthquakes. The main objective of the study is to perform a seismic vulnerability assessment of the MacArthur Bridge in Manila using the fragility curve based on Pushover Analysis and Capacity-Spectrum Method. To plot the fragility curve, the structural plan of the MacArthur Bridge was modelled using the CSiBridge The result from the Pushover Analysis, the yield displacement and maximum displacement when subjected to gravity loads and result from Capacity-Spectrum Method, the ductility demand were used to generate the seismic fragility curve. The fragility curve shows that there is a 28.99% chance of Slight Damage when 0.4g peak ground acceleration occurs in both East-West and North-South