OTREC-RR-10-17

This study examines retrofitting bridge brace elements with fiber reinforced composites to provide restraint against buckling. The composites are fiber reinforced polymer (FRP) composite pultruded sections and wet lay-up wraps. Prototype specimens were tested using reverse cyclic loading, and their performance was characterized by their compressive strength and their overall hysteretic behavior. This exploratory study shows that retrofitting slender bracing members with FRP sections improves performance. All retrofitted specimens show improved compressive strength in the linear elastic and plastic deformation range of the slender bracing member. The cyclic behavior had only a marginal improvement due to failure at the bolted brace connections. Brace modification marginally improved cyclic performance. Despite the challenges of connection failures, applying fiber reinforced composites has a potential to restrain buckling of slender bracing members and to improve compressive resistance.