Deformed steel bar is the common name of hot-rolled ribbed steel bar. The grade of ordinary hot-rolled steel bar is composed of HRB and the small value of yield point of grade. H. R and B are the English first letters of hot rolled, ribbed and bars respectively. Hot rolled ribbed steel bars are divided into three grades: HRB335 (old brand 20MnSi), HRB400 (old brand 20MnSiV, 20MnSiNb, 20mnti) and HRB500. zmjt039
Reinforcement for reinforced concrete refers to straight bar or coiled bar steel used for reinforcement of reinforced concrete. Its shape is divided into smooth round reinforcement and deformed reinforcement, and the delivery status is straight bar and coiled bar.
Plain round steel bar is actually small round steel and round steel of ordinary low carbon steel. Deformed reinforcement is the reinforcement with ribs on the surface, usually with two longitudinal ribs and transverse ribs evenly distributed along the length direction. The shape of transverse rib is spiral, herringbone and crescent. Expressed in millimeters of nominal diameter. The nominal diameter of deformed reinforcement is equivalent to the nominal diameter of plain round reinforcement with equal cross section. The nominal diameter of reinforcement is 8-50mm, and the recommended diameters are 8, 12, 16, 20, 25, 32 and 40mm.
Reinforcement mainly bears tensile stress in concrete. Due to the action of ribs, deformed reinforcement has great bonding capacity with concrete, so it can better bear the action of external forces. Steel bars are widely used in various building structures, especially large, heavy, light thin-walled and high-rise building structures.
Weight calculation formula: w = 0.00617 × d × D = section diameter, mm.
Parameters of hot rolled deformed bar
Brand: HRB335, HRB400, HRB500
Nominal diameter a mm: 6-25 28-50, 6-25 28-50, 6-25 28-50
Bending center diameter of bending test: 3A, 4a, 5A, 6a, 7a.