Seismic enhancement of circular RC bridge piers with fiber composites

The quasi-static test was conducted in a displacement-controlled way to research the seismic behavior of reinforced concrete columns strengthened with glass-fiber sheets. Six concrete bridge pier specimens were constructed using the starter bars that were lapped with the main longitudinal reinforcing steels, in a 1/2.83 dimensional scale factor. The unidirectional glass-fiber sheets were impregnated with epoxy mortar and wrapped around the plastic hinge region of the specimens. All specimens were tested under inelastic reversal loading while simultaneously subjected to a constant axial load θ.1FckAg. Test results show that the seismic performance of retrofitted concrete columns significantly improved as a result of the confining action of the glass-fiber composite straps. The straps are highly effective in confining the core concrete and preventing the longitudinal reinforcing steels from buckling under cyclic loading.