Study On Mechanical Properties Of High-performance Steel Fiber And Synthetic Fiber Concrete

Concrete is a kind of brittle material, its tensile strength and tensile strain are lower, in the engineering, tensile or shear need steel and concrete to stand together, in this case, the fiber reinforced concrete came into being. Since the last century the research of fiber concrete had just bengan, the research of steel fiber started relatively early, theoretical system of steel fiber compared to plastic fiber start to study the relative mature, however, we started to study plastic fiber lately, the research was delay, The main principle of the analysis of fiber reinforced concrete was based on the basic mechanical properties, to study the law the mechanical properties of the concrete was affected by fiber, combined with the test results, to Study and to compare steel fiber and plastic fiber how to reinforced and toughening concrete, at last comparing the economic benefits of the steel fibers and plastic fibers, to tell us the substitutability of plastic fiber on steel fiber.At first we can get the mechanical properties of concrete from the experimental research, on the experiment of compressive strength, the compressive strength of steel fibers and plastic fibers increased on different degree with the growth of the fiber content, the compressive strength of steel fibers increased15%, and the plastic fibers was limited in5%;with the growth of the fiber content, flexural strength increased on different degree, the flexural strength of steel fibers increased50%, the flexural strength of steel fibers increased30%; with the growth of the fiber content, on the experiment of direct tension, the tensile strength increased on different degree, the tensile strength of steel fibers increased25%, the tensile strength of steel fibers increased20%, their corresponding peak strain had also increased; when the rate of fiber volume had increased,the fracture energy and fracture toughness increased, the fracture toughness of steel fiber was between0.28to0.40, the fracture toughness of plastic fiber was between0.26to0.35, the fracture energy of steel fiber was between400to550, the fracture energy of plastic fiber was between400to500. At second, comparing and obtained the cost advantages of plastic Fiber,the cost of steel fiber was11.7w/m3,and the cost of plastic fiber was1.98w/m,on the same rate of fiber volume, the plastic Fiber’s cost-effective was higher, the cost of the unit volume of plastic fiber was17%of steel fiber’s. At last, because plastic fiber was mixed uniform easier, corrosion resistance, weight is small, the cost of unit volume was relatively inexpensive, so when plastic fiber meet the requirements of the project on the mechanical properties of concrete, plastic Fiber can be used to replace steel fiber.