| Easily installed and inspected fiber reinforced plastic (FRP) as an alternative to steel for restrainer construction to reduce bridge hinge movements during earthquakes was examined. Glass, carbon, and hybrid (glass/carbon) restrainers were constructed and dynamically tested in the large-scale structures laboratory. Work included: (1) Tensile tests on FRP strips and on FRP/concrete bond versus loading rate; (2) FRP restrainer development, including dynamic testing; (3) Shake table data analysis and comparisons of FRP, steel, and SMA restrainer performance; (4) Development of a FRP restrainer design method. Findings confirm FRP restrainer potential for future implementation to structures. Results include: (1) FRP strength is strain-rate insensitive; (2) FRP/concrete bond strength is a function of concrete shear strength and is strain rate sensitive; (3) Flexible restrainer construction and restrainer/concrete bond methods are demonstrated; (4) A simplified FRP restrainer design method, more realistic than AASHTO, and that considers bridge structure dynamic characteristics, is proposed. |
