Experimengt Study On Reinforced Concrete Beam Strengthened By Hybrid Fiber

With the development of society and the civil engineering technology,the concrete strength is increasing.Meanwhile the big brittleness ang low tensile strength are severely restricted.Fiber reinforced concrete,which are the most studied and the most widely used objects is an effective approach for solving the weakness.lt can effectively improve its tensile strength、 deformation capacity and endurance.Starting with the fiber reinforced concrete,first,we analyze characteristic and the development situation of the steel fiber concrete、polypropylene fiber concrete and the polypropylene imitation of steel fiber reinforced concrete. Through the experimental study,we study an new polypropylene fiber concrete-the polypropylene imitation of steel fiber reinforced concrete,and compare with the polypropylene fiber concrete,while mixed with the steel fiber.To this new style material,we proceeded a flood of experiment research,including the compressive strength test、the tensile strength test and the dynamic modulus of elasticity test.Foremore we contrast them with the common concrete and the fiber reinforced concrete, when they are used into the concrete member. At the same time, we study the deformation、cracks and the deflection under the influence of the different percentage of the fiber.by the analysis,we get optimization of the the fiber which can be used in the actual engineering.The result of experiment indicate that the beam is best with the0.5%volume content the steel fiber reinforced concrete and0.5%volume content the polypropylene imitation of steel fiber reinforced concrete, when we study the normal section strength and the inclined section strength of the concrete beam.The beam,which contant the steel fiber reinforced concrete mixed with the polypropylene imitation of steel fiber reinforced concrete, have good effect on avoiding the cracks and increasing the toughness.And the further research need is proposed.