Research On The Enhance And Anti-crack Performance Of Steel Fiber In Concrete Structure

After reading a large quantity of references about steel-fiber concrete, the author summarizes basic characteristics of SFRC in the dissertation and affirms that the steel fibers in concrete can enhance the intensity and tenacity of concrete structure. The dissertation mainly discusses steel fiber's enhancement and anti-crack function in concrete from two angles of the material's thermodynamics characteristic and the structural design method:Firstly, by comparing with two pier-wall structure models which are made of steel fiber reinforced concrete (SFRC) or ordinary concrete (OPC), The properties of temperature and strain in early aged concrete are revealed and researches the steel fiber influence on early period concrete's thermodynamics characteristics. Based on FEM, the experiment models are numerically simulated by using Ansys, and then the dissertation analyzes the temperature and stress distribution characteristics of the two different pier-walls at different time. By comparison with the test results, steel fiber's influence on temperature and stress of early period concrete structure are studied and the reason why steel fiber can improve concrete structure's anti-crack function is explained from its thermodynamics angle.Secondly, after using other's experiment achievements, the dissertation analyzes anti-crack mechanism of steel fiber in the SFRC beam. The design method i.e. partial section of reinforced concrete beam has been put forward. On the foundation of referring other's achievements, SFRC's bearing capacity, crack width and mid-span's displacement's variety regulation under the influence of steel fiber reinforced concrete at different heights are analysed by using Ansys. Thus the design method of partial section of reinforced concrete beam reinforced by steel fiber proves to be more accuracy and more reasonable. It is useful for practices.