GB1499.2-2024

Steel for the reinforcement of concrete—Part 2:Hot rolled ribbed bars

钢筋混凝土用钢第2部分：热轧带肋钢筋

GB 1499.2-2024 es una norma nacional china obligatoria vigente: Steel for the reinforcement of concrete—Part 2:Hot rolled ribbed bars. Sector: Electrónica. Enfoque: Seguridad de productos. Entrada en vigor: 25 sept 2024.

La aplicabilidad depende del alcance del producto, la vía de certificación, los avisos de la autoridad competente y las reglas de transición. Solicite una traducción o verifique la fuente antes de usar esta ficha en una decisión de cumplimiento.

Resumen de cumplimiento

Este resumen está disponible por ahora solo en inglés.

Alcance y aplicabilidad

This standard applies to hot rolled ribbed bars (ordinary and fine-grain) used for the reinforcement of concrete. It covers various grades including HRB400, HRB500, HRB600, and their seismic variants designated with an E suffix. It is not applicable to recycled steel bars re-rolled from finished steel products or quenched and self-tempered (QST) bars.

Requisitos técnicos

The standard comprehensively defines the dimensional parameters, chemical composition, and mechanical properties for concrete reinforcement bars. It specifies the nominal diameter range (6mm to 50mm), cross-sectional areas, and theoretical unit weights. Strict tolerances are established for weight deviations, rib geometry, and bending characteristics to ensure structural integrity. Regarding material composition, the standard sets upper limits for critical elements such as carbon, silicon, and manganese, alongside strict controls on carbon equivalent (Ceq) and nitrogen content. The mechanical properties section mandates minimum characteristic values for yield strength, tensile strength, elongation, and maximum force total elongation. Seismic grades (E-designated) must meet specific tensile-to-yield strength ratios to guarantee energy dissipation during earthquakes. Additionally, the standard outlines requirements for bending and reverse bending performance, ensuring the bars do not crack under specific bending diameters. For specialized applications like railway bridges, fatigue performance testing is mandated. It also sets criteria for metallurgical structure, prohibiting tempered martensite on the core circle, and requires fine-grain bars to achieve a grain size of grade 9 or finer.

Métodos de ensayo

Testing protocols include tensile, bending, and reverse bending tests conducted on non-machined specimens. Chemical composition is verified via spectroscopic methods, with reference to GB/T 4336 and GB/T 223 series standards for arbitration. Dimensional verification involves precise measurement of inner diameter, rib height, and spacing. Macroscopic metallographic, Vickers hardness, and microstructure tests are employed to detect any improper heat treatment like quenching. Furthermore, fatigue performance is evaluated according to GB/T 28900 for dynamic load structures.

Preguntas frecuentes

What products are regulated under GB 1499.2-2024?

The standard applies to hot rolled ribbed bars for concrete reinforcement, including both ordinary and fine-grain types. It explicitly excludes rebar rolled from finished steel products and quenched and self-tempered bars.

What are the main updates in GB 1499.2-2024 compared to the 2018 version?

The 2024 edition transitions from a recommended to a mandatory national standard. Key updates include revised weight tolerance limits, updated fatigue performance requirements, new sampling rules for dimensions, and changes to mixed-batch criteria and packaging regulations.

How are the rebar grades designated in this standard?

Grades are designated by HRB (Hot Rolled Ribbed Bars) or HRBF (Fine Grain) followed by a yield strength value (400, 500, 600). The suffix E (e.g., HRB400E) indicates seismic grade bars with specific tensile-to-yield ratio requirements for earthquake-resistant structures.

The summary above provides a high-level overview of GB 1499.2-2024. To ensure complete compliance for your construction materials entering the Chinese market, a precise and professional translation of the full technical specifications is essential. Purchase our high-quality English translation of GB 1499.2-2024 today to access all detailed parameter tables, dimensional tolerances, and precise testing procedures.

Indicaciones de aplicabilidad

Tipo: Producto
CCS: H44
ICS: 77.140.15
Organismo competente: Ministry of Industry and Information Technology
Comité técnico: National Technical Committee on Steel of Standardization Administration of China

Relaciones

Sustituye a:GB/T 1499.2-2018