Experimental Study On Mechanical Properties Of Hybrid Fiber Reinforced Cement - Based Composites

In order to study the mechanical properties of hybrid-FRCC under the load of different strain rate, the influence of the basic mechanical properties, fracture properties, impact resistance and resist blasting performance of Hybrid-FRCC affected by fiber volume ratio, fiber types, proportion of hybrid-fiber and water-binder ratio are obtained through the contrast test about the mechanical of dynamic and static in this paper. The main experimental and theoretical work includes the following aspects:(1) In order to obtain the influence of fiber and water-binder ratio on the static mechanical properties of the Hybrid-FRCC, three point bending test, compressive strength test and the experiment of fracture energy were conducted. The results indicate that:the bending strength and fracture properties of Hybrid-FRCC are remarkably improved because of the incorporation of fiber, but the compressive strength had no remarkable change; within some rage, the static mechanical properties of the Hybrid-FRCC is improving along with the improvement of the fiber volume ratio, otherwise, over high fiber volume ratio will make the negative effect on the mechanical properties when beyond the rage; under the same condition of fiber volume ratio, the strength of SE-FRCC is superior to Hybrid-FRCC; the strength of Hybrid-FRCC is down trading along with the increasing of the water-binder ratio.(2) In order to obtain the influence of the fiber and water-binder ratio on the impact resistance of the Hybrid-FRCC, the experiment of impact resistance was conducted. The results indicate that:the impact resistance of the Hybrid-FRCC is improving along with the improvement of the fiber volume ratio; the fiber of SE makes the dominate function to the improvement of the impact resistance of the Hybrid-FRCC, secondly for the fiber of PVA; the toughness of the Hybrid-FRCC improved with the increase of the water-binder ratio; the higher dispersion of the fiber, the lower discreteness of the experimental results.(3) In order to obtain the influence of the fiber on the resist blasting performance of the Hybrid-FRCC, the experiment of resist blasting performance was conducted. The results indicate that:the resist blasting performance of the Hybrid-FRCC improved with the increase of the proportion of fiber volume ratio between SE and PP or PVA; compared with the fiber of PVA, the fiber of PP makes the better improvement on the resist blasting performance of the Hybrid-FRCC; the fiber of SE makes the dominate effet on improving the resist blasting performance of the Hybrid-FRCC.