Replacing traditional steel rebars with glass fiber-reinforced polymer (GFRP) cages in precast concrete tunnel segment linings is feasible. Using GFRP rebar in precast tunnel segments as structural reinforcement has multiple advantages for structural durability or temporary linings that need to be removed later. Additionally, this type of reinforcement may be suitable for creating dielectric joints that ensure the interruption of stray currents, which often cause corrosion issues. However, this particular application requires curved shapes of the rebar, necessitating different production processes and rebar geometries. The current work provides optimization suggestions for GFRP materials in tunnel segments. Four GFRP cage structures were analyzed and used as comprehensive reinforcement for tunnel segments. Bending and point load tests were conducted, and the structural performance of the samples was compared and discussed. Finally, the optimal solution in terms of cost-effectiveness was proposed.
