Experimental Study On Impact Resistance Of Synthetic Fibre Reinforced Concrete

With its improvement mechanism of concrete performance, competitive price and corrosion resistance, synthetic fiber is of advantage to fiber reinforced concrete to enhance the status in today’s engineering applications and concrete future development. Fiber reinforced concrete, which is mainly applied to the bridge deck pavement, runway and apron, road pavement, port construction to withstand repeated dynamic loads, the structure, and so on, turns out to be particularly important to the study of the impact resistance of fiber reinforced concrete at present.Focusing on the impact resistance of fiber reinforced concrete, the paper carries out an experimental investigation into Polypropylene fiber reinforced concrete and Polyvinyl Alcohol fiber reinforced concrete with the Drop-weight impact test. Experiments have been done on specimen made of fine mortar containing0.1%、0.35%and0.6%of four types of PP fibres and two types of PVA fibres on the self-made improved Drop-weight impact test device. By testing the impact resistance of every group of fiber reinforced concrete,studies are taken on the mechanism of the fiber reinforced concrete’s impact resistance, as well as the effects on performance of concrete, which are made by different contents and types of the fiber.In the Study of the impact tests on the fiber reinforced concrete that are in the same strength grade,some useful conclusions are drawn as follows:All types of Synthetic fibers/which is used as an additive, can obviously improve the impact resistance of concrete. In certain scale, a positive linear relationship is shown between fiber content and the impact resistance of concrete. Fiber help concrete increase the fracture number and penetration depth. For Polypropylene fiber:Short fiber increase large number blows at first crake; Long fiber has greater advantages of improving the ductility than short fiber; Mesh short fiber concrete has the largest number blows at failure. Polyvinyl Alcohol fiber with high elastic modulus can resist the impact before first crake. PVA fiber with small ratio of length to diameter show better ductility than large one. Impact test results of large discreteness, improve the fiber dispersion is helpful to reduce the discrete coefficient.