Experemental Study On Shear Capacity Of Reinforced Concrete Beam With 500MPa Hot Rolled Bars Of Fine Grains

500MPa hot rolled bars of fine grains is a new type of fine‐grained steels, which is a new research and development of our country according to the technology that control the temperature. It's a new type steel bar which has many merits, such as hi‐strength and strong ductility. Now this kind of steel bar has been taken in by《Hot ribbed bar of reinforced conrete》(GB1499.2‐2007) which started in March 2008, but it hasn't been taken in by《Code for design of concrete structures》(GB50010‐2002), because the domestic study of this new king of steel bar strart late and the relevant testing information is absent.Based on the experiments of 16 concrete beams with 500MPa hot rolled bars of fine grains, 1 with HRB400 bars and 1 with HRB600 bars as stirrup under concentrated load. They are observed that the crack, deflection, bearing capacity and failure mode when the strength grade of concrete, shear span ratio, stirrup strength, stirrup ratio, sectional dimensions, cross‐sectional shape, such as conditions are not at the same time, some comparisons are made between test results and calculated values.Based on the test results , discussing the beams with 500MPa hot rolled bars of fine grains as stirrup which diagonal crack width can or not satisfy the engineering requirements for applicability and durability The testing results indicate that 500MPa hot rolled bars of fine grains'design strength of extension take 420MPa, if the influence coefficient of long term sustainned loading takes 1.5, the limitation of concreter structure diagonal crack width's requirement can be satisfied during the state of regular service. The propositional design strength is discussed when the 500MPa hot rolled bars of fine grains as stirrup. Based on the analysis of experimental results, in the formula in code for design of concrete structures, the propositional design strength of 500MPa hot rolled bars of fine grains is 420MPa.At the basis of the experiment, the reinforced concrete beams were analyzed by the nonlinear finite element method. The process of the experiment are simulated with the finite element software ANSYS. From the comparison of the numerical results and experimental ones, it can be seen that the numerical shows excellent agreement with the experimental ones.