Exrerimentl Study On Shear Performance Of Syeel Fiber Reinforced Concrete T-beam Without Stirrups

Steel fiber reinforced concrete(SFRC)is a new kind of multiphase composite material formed by adding short steel fiber with random distribution in ordinary concrete,which significantly improves the mechanical properties of concrete.SFRC can effectively hinder the development of internal cracks of concrete and increase the ductility of concrete.SFRC beams are quite different from ordinary concrete beams in terms of failure forms,mechanical properties and other aspects.In this paper,a shear test was carried out on SFRC T-beams without stirrups,which provided a reference for the feasibility of using steel fiber in T-beams.The main contents of this paper are as follows:(1)In this paper,ten SFRC T-beams without stirrups and two ordinary concrete T-beams without stirrups were tested.During the test,the development and extension of cracks in the test beams were observed.Meanwhile,the displacement was measured.The main strain values of concrete in the shear span area and the strain changes of concrete in the shear compression area were measured.(2)The influence of steel fiber volume fraction on the cracking load of SFRC T-beams without stirrups was studied.The formulas for calculating cracking load were analyzed and verified by tested data.(3)The effect of steel fiber volume ratio on the shear force of steel fiber reinforced concrete reinforced T-beam without web reinforcement is analyzed.Combined with their own test data of some scholars,the shearing resistance of SFRC beams was calculated according to the relevant specification,which suggested that the formula of shear resistance on SFRC beams without stirrups can be used for SFRC T-beams without stirrups and had good agreement with the test.