A Study on the Lifecycle Cost of a Concrete Bridge using FRP in Chloride Attack Environments

 ABSTRACT

Analysis was conducted on the life-cycle cost (LCC) of using fiber-reinforced plastic (FRP) to reinforce a concrete bridge exposed to a chloride environment. Japan faces the serious problem of increased maintenance costs from bloc obsolescence of bridges, at a time of shrinking public works budgets. We face a demand for cost reduction and improved durability of infrastructure. FRP is highly durable, but its construction as reinforcement costs more than that for steel. To examine the cost performance of FRP on a concrete bridge (span length: 18 m) exposed to a chloride environment, we compared four cases in terms of LCC and initial construction cost. Case 1 uses conventional concrete cover with protective coating for reinforcement. Case 2 uses FRP only for reinforcement. Case 3 uses FRP reinforcement in conjunction with prestressed concrete (PC) strands. Case 4 uses electrochemical protection. The lowest initial construction cost was for Case 1 (=100%), followed by Case 3 (106%), Case 4 (115%), and Case 2 (123%). The lowest LCC was for Case 3 (69% of the LCC for Case 1), followed by Case 2 (88% of the LCC for Case 1) and Case 4 (130% of the LCC for Case 1). Our study confirms that FRP retrofit of concrete bridges in a chloride attack environment reduces LCC.