Seismic Behavior of Historical Masonry Bridges: The Case Study of Irgandi Bridge

Abstract

 In Anatolia, numerous bridges have been constructed throughout history for essential reasons. It is important to preserve the bridges and hand them down to the future generations as they have hints regarding the materials and construction techniques used in the past. Irgandi Bridge located on Gökdere in Bursa city, which is the first capital of the Ottoman Empire, has a special importance among bridges around the world. It is one of the few bridges around the world, which have had commercial activities with shops on it along with the purpose of transportation. This symbolic structure in terms of cultural, historical and constructional aspects is located in Bursa which includes 1st degree seismic hazard zone. Therefore, preservation of the bridge requires investigation of its seismic performance and taking necessary precautions. Irgandi Bridge was modeled by ANSYS software using finite element method (FEM). Convergence study was performed to determine the accurate number of elements. Modal and linear dynamic analysis of the Irgandi Bridge was conducted after the number of elements were determined by the convergence study. Therefore, seven earthquake records were scaled and performed to the system according to EC-8 (Eurocode-8). Stress distributions and displacements were examined as a result of linear dynamic analysis. It was determined that the maximum displacement occurred at the top of the bridge and the principal stress occurred in the support regions. As a result of the analyses, it was proposed to strengthen the support parts of the bridge, which were determined to be damaged under earthquake impact.