Description Class A3 Reinforcement (with periodic profile) are steel bars with a ribbed surface, designed for reinforcing reinforced concrete structures. They are one of the most common types of reinforcing materials in construction. Production Technology The manufacturing process includes several stages: 1. Raw Material Preparation: Steel billet – wire rod of the required chemical composition – is used. 2. Heating: The billet is heated to temperatures of 1000-1200°C to impart plasticity. 3. Rolling: In rolling mills, through a system of rolls, a bar of the specified diameter with a periodic profile is formed. 4. Cooling: After rolling, the reinforcement undergoes controlled cooling. 5. Cutting and Straightening: Cut to measured lengths and straightened. 6. Thermal Strengthening: Some reinforcement is subjected to heat treatment to increase strength. Characteristics and Assortment • Bar Diameters: from 6 mm to 80 mm. • Strength Class: A400, A500C, A600, A600C, A600K, A800, A800K, A1000. • Strength Characteristics: o Yield strength: 400-1000 MPa. o Tensile strength: 600-1200 MPa. o Elongation: 14-25%. • Length: bar 11.7 m or in coils (for small diameters). Advantages • High Strength and reliable bond with concrete. • Resistance to dynamic and static loads. • Good Weldability (for marking "C"). • Resistance to stress corrosion cracking (for marking "K"). • Versatile Application in various structures. • Compliance with international quality standards. Areas of Application • Monolithic Construction: foundations, columns, floors. • Precast Reinforced Concrete Production: panels, beams, slabs. • Road Construction: road slabs, bridge structures. • Construction of reinforced masonry structures. • Strengthening of slopes and embankments. • Production of reinforced concrete products for various purposes. Normative Documentation (GOST Standards) Main standards regulating the production of Class A3 reinforcement: GOST 34028-2016 – "Reinforcing rolled products for reinforced concrete structures. Technical specifications" • Defines technical requirements for reinforcing rolled products. • Establishes classification and marking. • Regulates test methods and quality control. GOST 5781-82 – "Hot-rolled steel for reinforcing reinforced concrete structures" • Establishes assortment and mechanical properties. • Defines acceptance and testing rules. • Regulates marking and packaging requirements. Additional Normative Documents: • GOST 10884-94 – Thermomechanically strengthened reinforcement. • GOST 52544-2006 – Welded periodic profile reinforcement. • SP 63.13330.2018 – Concrete and reinforced concrete structures. Reinforcement Marking: • A – reinforcement. • Number – yield strength (400, 500, 600, etc.). • C – weldable. • K – corrosion-resistant.