Today, reinforcement and upgrading of structures is one of the important topics in civil engineering. Corrosion of reinforced concrete in marine environments is one of the main problems in the ports of the world. In this research, one of the commercial docks of the Amir Abad port of Behshahr, Mazandaran, which has been observed during field visits, that its concrete piles have been severely corroded, is being restored and evaluated. For this purpose, a dock was first modeled in the SAP2000 software. In order to investigate the operation of the piles of the dock, three conditions: before corrosion, after corrosion and after repair, static nonlinear analysis was performed. In this research, restorative concrete such as self-compacting concretes and non-condensed concrete Conbextra UW as well as different fibers of FRP composites were used to repair piles. The results of this study indicate that the use of FRP composites for the repair of piles has the best performance in terms of the horizontal displacement of the deck of the deck and the maximum tolerance of the shear force produced in the piles compared to the restored piles using restorative concrete. According to the results of this study and considering the durability and resistance of materials to corrosion, as well as the cost of supplying and implementing materials for the repair of piles, the use of FRP composites in terms of tools and economics is the proper option for the repair of piles.