Compression strength of concrete columns reinforced by non-adhesive filament wound hybrid composites

Abstract

In this study, epoxy resin impregnated hybrid fiber bundles were wound onto a concrete column wrapped by a piece of aluminum foil, and cured. Two kinds of layup of the hybrid composite were studied: first, carbon or Kevlar angle-plies sandwiched by glass hoop layers; second, carbon or Kevlar hoop layers sandwiched by glass angle-plies. Compressive strengths of concrete columns reinforced by non-adhesive (since separated by the aluminum foil) filament wound hybrid composites were measured, and related damage mechanisms were investigated. The hybrid composite jackets on wound columns are stronger than the hybrid composite tubes even when the strength of concrete columns inside the wound columns is excluded. Further, compressive strengths for the wound columns with the first kind of layup increase with the winding angle of angle-plies. And the ductility of hybrid composite wound columns is higher than that of glass/epoxy wound columns. The damage mechanisms for various columns were proposed based on our experimental observation. The results promote a potential application of hybrid composites for repairing of infrastructure.