GB/T 33953-2025Corrosion resistance bars for the reinforcement of concrete (English PDF)

6.1 Smelting method

Steel shall be smelted in a converter or electric arc furnace and shall be secondarily refined.

6.2 Delivery condition and delivery type

6.2.1 Steel bars are usually delivered in a hot-rolled condition. High corrosion

resistance bars can be delivered in hot-rolled and pickled condition, while corrosion resistance bars can be delivered in controlled-rolled and controlled-cooled condition.

6.2.2 The delivery type of steel bars shall comply with the provisions of GB 1499.2.

7.1 Chemical composition

7.1.1 The chemical composition (cast analysis) of the steel bar shall conform to the specifications in Table 2.Elements such as Nb, Ti, and RE may be added to the steel.

Table 2 -- Chemical composition of steel bars (cast analysis) 7.1.2 The nitrogen content of the steel shall not exceed 0.012%, and the supplier is permitted not to conduct analysis. A higher nitrogen content is permissible if the steel contains a sufficient amount of nitrogen-binding elements.

7.1.3 The permissible deviation of the chemical composition of finished steel bars shall

comply with the provisions of GB/T 222.

7.2 Mechanical properties

7.2.1 The mechanical property characteristics of steel bars, such as lower yield strength

ReL, tensile strength Rm, percentage elongation after fracture A, and percentage total elongation at maximum force Agt, shall conform to the provisions of Table 3.Among the mechanical property characteristics listed in Table 3, R°eL/ReL is the maximum guaranteed value, and the others are the minimum guaranteed values.

7.2.2 For steel bars with a nominal diameter of 28 mm~40 mm, the percentage elongation after fracture (A) of each grade is allowed to be reduced by 1%; for steel bars with a nominal diameter greater than 40 mm, the percentage elongation after fracture (A) of each grade is allowed to be reduced by 2%.

Table 3 -- Mechanical properties of steel bars

7.3 Process performance

7.3.1 Bending performance

After bending the steel bar 180° according to the bending indenter diameter specified in Table 4, no cracks shall appear on the surface of the bent part. ......