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Now the compressive strength of the concrete is improved greatly, but the brittleness property becomes more obvious. When under axial compressive force, the toughness looks tiny and concrete always destroyed suddenly. After incorporating with steel fiber and polymer fiber of high elastic module in concrete, the toughness and tactility property are improved. But the property of fiber is variety and the composing impact greatly on the property of the concrete, so it’s necessary to research the special property of the hybrid fiber concrete.In this paper, the compressive strength, splitting tensile strength, flexural strength, dry shrinkage, stress-strain under axial compressive and bending toughness of the concrete incorporated with steel fiber and polymer fiber are studied. The volume content of the polymer fiber and the slenderness ratio of the polymer fiber compact on the properties of the concrete are studied in detail. In the experiment, the properties of the concrete changed greatly when the volume content of the polymer fiber incorporated with the concrete changed from 0 to 1.5% and slenderness ratio of the polymer fiber changed from 400 to 800.The results show that hybrid fiber have negative compact on the compressive strength of the concrete. The more the volume content of the polymer fiber incorporated with, the greater the impact is, and also the larger the slenderness ratio is, the greater the impact is. But the splitting tensile strength, flexural strength and dry shrinkage property are improved much better. What’s more important is that, after incorporating with hybrid fiber in concrete, the deforming property under pressure force is improved which made the concrete destroyed from brittle to ductile. The deforming property under axial compressive force and flexural force are improved greatly. When the volume content of steel fiber which the hybrid fiber reinforced concrete incorporated with is 0.5% for a certain value, and polymer fibers are 0.5%, 1.0%, 1.5%, respectively the toughness under axial compressive force are increased by 157.8%, 167.9%, 163.7%, and the bending toughness increased by 3.8, 4.0, 4.4 fold, compared with the plain concrete. When the slenderness ratio of the polymer fibers is 400, 800, respectively the toughness under axial compressive force is increased by 132.3%, 167.9%, and the bending toughness increased by 3.9, 4.0 fold, compared with the plain concrete. However, it will bring certain difficulties at the scene construction when the volume content of polymer fiber is too high and the slenderness ratio is too large. This is still a problem.
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