The mechanical and durability properties of concrete containing hybrid synthetic fibers

The results indicated that hybridization of PO with PP fibers can improve the compressive and splitting tensile strength of mixtures up to 7.5% and 23% compared to those of control mixture, respectively. However, the hybridization of these fibers did not show a positive effect on post-cracking behavior at the flexural test. From durability viewpoint, replacement of some part of PO fibers with PP fibers can control the negative effect of using PO macro fibers. However, at the high volume fraction of fibers, the hybridization of PO with PP fibers showed the negative effect. Based on an overall view of results, hybridization of PO and PP fibers at the volume fraction of 0.9% and 0.1%, respectively, can be recommended for practical usage. This combination of fibers decreased the corrosion of steel in RC beams and improved the key parameters of structural behavior such as yield and ultimate loading, and stiffness of beams.