The standard number is GB/T1499.2-2018 and will be officially implemented on November 1, 2018.

The main changes in this standard compared with GB/T 1499.2-2007 are as follows:

- increased smelting methods;

- canceled the 335MPa grade steel bar;

- an increase of 600MPa grade steel bars;

- increased the number of steel bars with E;

- Appropriate tightening of the length tolerance and bending;

- Appropriate tightening of the weight tolerance, clear weight deviation is not allowed to retest;

- The requirement for the reverse bending test of the steel bar with the grade E is used as a routine inspection item;

- Added provisions for fatigue test methods for steel bars;

- increased the rules for metallographic inspection;

- increased macroscopic metallographic, cross-section Vickers hardness, microstructure and test methods;

- a method of measuring the increase in the end of the transverse rib;

- Replace the surface mark with the "registered factory name (or trademark)" and "the production license number of the hot rolled steel bar for reinforced concrete obtained by the enterprise (the last 3 digits)", and delete the "nominal diameter of not more than 10 mm" Rebar, can not roll signs,

The method of hanging signs can be used";

- Removed Appendix A, "Methods for Measuring the Total Elongation of Rebar under Maximum Force".

This section uses the redrafting method to refer to ISO 6935-2: 2015 "Steel for reinforced concrete Part 2: Ribbed steel bars", and the degree of conformity with ISO 6935-2: 2015 is not equivalent.

This standard has the following provisions regarding the positive and negative bending of steel bars:

Bending performance

The steel bars should be subjected to a bending test. After bending the diameter of the bending head as specified in the following table, the surface of the steel bar shall not be cracked.