Type of steel plate suitable for construction projects

In construction engineering, steel plate as the core structural material, its performance is directly related to the safety, durability and economy of the project. However, there are many kinds of steel plates on the market, from ordinary carbon steel to special alloy steel, from hot rolled plate to galvanized plate, how to accurately select according to the project needs? This paper will systematically analyze the key material selection factors and provide practical suggestions.

Define the core requirements of the building project load-bearing and mechanical properties of high-rise buildings: high-strength low-alloy steel plates (such as Q345B, Q420C) should be prefered, whose yield strength can reach more than 345MPa to meet the vertical load and wind load requirements of super high-rise buildings. Large-span structure: High toughness steel plate (such as S355JR) is recommended to ensure cracking resistance under dynamic load. Case: Shanghai Tower adopts Q420C steel plate to reduce column section size and improve space utilization. Weather resistance and corrosion environment Coastal or chemical projects: weathering steel (such as Corten series) or galvanized steel (zinc layer ≥275g/m²) must be selected to resist salt spray and acid rain erosion. Ordinary factory: Ordinary carbon steel (such as SS400) with anti-rust paint can meet the needs, but need regular maintenance. Temperature adaptability in low temperature areas (such as Northeast, Northern Europe) : steel plates that need to meet low temperature impact work standards (such as ASTM A36-40 ℃ class) to avoid brittle fracture.

Thickness selection sheet (<3mm) : suitable for non-load-bearing enclosures (such as walls, roofs), lightweight and low cost. Medium thick plate (3-20mm) : Used for the main stress components such as beams, columns and trusses, the optimal thickness should be determined by ANSYS or Tekla structural simulation. Extra-thick plate (>20mm) : dedicated to super high-rise core cylinder, heavy equipment base, need to pay attention to the Z resistance to lamellar tear performance (such as Z15, Z25). The size and cutting process is preferred to choose the standard size of the steel mill (such as 2000×6000mm), and non-standard customization will increase the cost by 15%-30%. Laser cutting accuracy (±0.5mm) is better than flame cutting (±2mm), but the cost is higher, and it is suitable for precision connection nodes. Fire protection requirements: Choose the steel plate coated with fire retardant coating (fire resistance limit 1-3 hours), or directly purchase composite fire protection board (such as Baosteel BFP series). Aesthetic requirements: Pre-painted color steel plate (PE/PVDF coating) can be selected to reduce the on-site spraying process. Third, cost control and supplier management strategy budget optimization skills Batch procurement: a single purchase volume > 50 tons can enjoy the steel mill direct supply price (lower than the market price 8%-12%). Alternative: Use hot-rolled plate instead of cold-rolled plate in non-critical parts, saving about 20%. Supplier selection criteria Certification qualification: Ensure that suppliers have passed ISO 9001 quality management system certification, and provide MTC (Material Certificate) of steel. Testing capability: Third-party testing reports (such as SGS, BV) are required, focusing on the verification of chemical composition (C, Mn, Si content) and mechanical properties (yield strength, elongation). Risk avoidance contract terms: clear delivery delay compensation (0.1%-0.3% liquidated damages per day), substandard quality return and exchange terms. Inventory management: JIT (just-in-time) procurement is adopted to avoid rust losses caused by open storage of steel plates.

Industry trend: Green steel and intelligent material selection of environment-friendly steel plate EU standard EN 10025-5 S355J2W weathering steel, can reduce maintenance costs by more than 30%. "Zero-carbon steel plates" produced by hydrogen metallurgy processes (such as Sweden's SSAB's HYBRIT technology) reduce carbon emissions by 95%. Digital tool applications use BIM software (such as Revit) to integrate steel sheet property data and automatically match project requirements. Through the steel data, my steel network and other platforms real-time price comparison, lock the low-cost procurement window.

Choosing steel plates for construction is not simply "the thicker the better" or "the more expensive the safer", but requires comprehensive mechanical properties, environmental adaptability, processing costs and supply chain reliability. It is suggested that the engineer and the procurement team jointly formulate the Technical Specification of the Project Steel plate, and establish a hierarchical management system for suppliers, so as to finally realize the triple optimization of quality, cost and construction period.