Effect of Fibers on Development/Splice Strength of Reinforcing Bars in Tension

The effects of fibers on development/splice strength of reinforcing bars in tension were experimentally investigated. Three series of tests, with five beams each, lap spliced at midspan, were carried out. The research parameters were: bar diameter (d sub b) fiber type, fiber volume fraction (V sub f), and fiber reinforcing index (V sub f L/d sub f). The beams were loaded in positive bending with constant moment along the splice region. The current experimental results demonstrated clearly that the use of hooked steel fibers in concrete matrixes increases significantly the development/splice strength of reinforcing bars in tension. While the use of polypropylene fibers, added in 0.6 percent by volume, improved the bond performance in the post-splitting range, they were not as effective as steel fibers in increasing the development/splice strength of the reinforcing bars.