EXPERIMENTAL STUDY ON BOND-ANCHORAGE OF HOT ROLLED RIBBED BARS OF FINE GRAINS IN CONCRETE

Hot rolled ribbed bars of fine grains are new type of steel bars with high strength and good ductility,its characteristic value of yielding strength is 500 MPa.Experiment in bond-anchorage of the new re-bars was performed through 25 groups(75 pieces) of pull-out specimens,the main factors that affect the bond-anchorage strength such as the strength of concrete,the development length of bars,the diameter of bars,the cover thickness of concrete and the transverse steel ratio were analyzed.The results show that the bond-anchorage property of hot rolled ribbed bars of fine grains in concrete is almost the same as the common hot rolled ribbed bars,the anchorage development length of the new re-bars can be designed with the stipulations in Code for Design of Concrete Structures(GB 500102002).This proposal may be as a reference for the applications of hot rolled ribbed bars of fine grains in projects.