Document Type : Research Article
Department of Civil Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran
Bridges are of the most important and vulnerable crucial paths that damages to them result in significant financial disadvantages. A great part of the past technical and artistic documents are related to the bridges and their construction techniques. Preservation of the historic bridges that are currently in use has particular importance. One of the historic bridges around Tehran that is located in the Firouzkuh fault zone, is Namroud bridge. In the current study, the Namroud Stone Arc Bridge was investigated under strong ground motions to assess the weak points and to improve its behavior by retrofitting it. For this purpose, the finite element method was used for both modeling and nonlinear analyses under five near field earthquake records. By recognizing the masonry bridge weaknesses, FRP material was used in order to retrofit the bridge. The results reveal that although the studied bridge is vulnerable to the earthquakes, it can maintain its stability. Further the vertical acceleration component has an important effect on the vulnerability of the structure. Adding FRP sheets to the bridge deck was expressively effective whereas in other parts such as piers connection with the spandrel walls, leads to the spread of damage. Also in the location of the small openings there is no possibility of the desired performance of FRP materials. Thus other methods such as planting rebar, injection and etc. should be used for these areas. Furthermore, it is impossible to use FRP material to achieve an economical and efficient method for retrofitting all bridge parts.