Effects of structural fibers on bonding mechanism changes in interface between GFRP bar and concrete
The steel rebar, sand-coated and helically-wrapped types of GFRP bars with a total of 63 cubic specimens were prepared with structural fibers (steel, PP and PVA fibers) in this paper. The results of direct pull-out testing were presented and analyzed with the aim of elucidating the effect of surface treatment of bar, fiber type, and fiber content in interface and suggesting the effective evaluation method for the improved ductility. The structural fibers in the interface changed the interfacial bond behaviors before and after the maximum stress and resulted in significant improvement of the relative bond strength, but bond failure modes largely depended on the interfacial property with the rebar. The fiber's crack closing resistance determined by evaluating both residual bond strength and toughness indices was used to determine optimum amount and type of fibers in composites. The Among fiber type, the closing pressures due to PVA and hook end steel fibers had a good effect on resisting and controlling of the interfacial crack initiation, growth, and propagation.
Composites Part B: Engineering
© 2011 Elsevier. This is the author-manuscript version of this paper. Reproduced in accordance with the copyright policy of the publisher. Please refer to the journal's website for access to the definitive, published version.