Evaluation of FRP Posttensioned Slab Bridge Strips Using AASHTO-LRFD Bridge Design Specifications

Abstract

Deterioration of concrete structures caused by corrosion of steel reinforcement requires large capital investments in order to repair or replace existing structures which may or may not be nearing the end of their expected service lives. Fiber-reinforced polymer (FRP) reinforcement has emerged as a viable alternative to conventional reinforcement with lower life cycle costs. Serviceability typically governs the design of FRP structures because of the inherent low stiffness of FRP materials. As a result, concrete members tend to exhibit high deflections, large crack widths, and a reduction in shear capacity compared to similar steel-reinforced members. This study focuses on glass fiber–reinforced polymer (GFRP) reinforced slab strips cast with self-consolidating concrete (SCC) and posttensioned with carbon fiber–reinforced polymer (CFRP) tendons to improve the serviceability, shear capacity, and deformability of slab bridges. The flexural performance of five FRP slabs and one steel-reinforced control slab are compared to the design provisions of the AASHTO Load and Resistance Factor Design (LRFD) Bridge Design Specifications.