Prestressed concrete steel wire: high-strength material helps modern infrastructure upgrade

With the rapid development of infrastructure construction in China, prestressed concrete steel wire, as a key material, is becoming the core support for bridges, sleepers, high-rise buildings and other projects due to its excellent mechanical properties and wide application scenarios. This article will interpret the technological advantages of this "invisible hero" from three aspects: material characteristics, mainstream models, and industry applications.

1、 Material characteristics: High strength and corrosion resistance are equally important
The prestressed concrete steel wireis made of high Carbon Steel (with a carbon content of 0.6% -0.85%) through cold drawing or stabilization treatment, and has the following characteristics:

High strength: The tensile strength can reach 1470-1860MPa, which is 3-4 times that of ordinary steel bars;

Low relaxation: Through stabilization treatment, the stress loss rate can be controlled within 2.5%;

Durability: The surface can be coated with zinc or epoxy to resist concrete carbonation and chloride ion erosion.

2、 Mainstream models and standard specifications
Domestic common models are classified according to national standards (GB/T 5223, GB/T 5224):

Smooth steel wire: Φ 4.0mm - Φ 7.0mm, mostly used for pre tensioned prestressed beams;

Spiral ribbed steel wire (such as Φ H7.0mm) enhances the bond strength with concrete;

Scratched steel wire: surface indentation design, suitable for post tensioned prestressed tendons;

Galvanized steel wire: anti-corrosion type, used for corrosive environments or cable-stayed bridge cables.

International standards (such as ASTM A416) are divided into two categories: "low relaxation" and "normal relaxation", with a diameter range of 3mm-12mm.

3、 Application scenarios: From infrastructure to new energy
Transportation engineering:high-speed rail sleepers, main beams of cross sea bridges (such as the Hong Kong Zhuhai Macao Bridge using Φ 7mm galvanized Steel Wire);

Construction field: super high-rise building floor slabs, nuclear power plant safety shells;

New energy: Pre stressing anchoring system for wind turbine tower;

Municipal construction: large pipe piles, prefabricated comprehensive pipe galleries.

Steel wire for prestressed concrete refers to a general term for steel wire made from high-quality high carbon steel wire rods that have been pickled, phosphated, cold drawn, or stabilized. Pre stressed steel wire can be divided into two types according to different production processes: cold drawn steel wire and stress relieving steel wire. According to different surface states, it can be divided into smooth steel wire, scratched steel wire, spiral ribbed steel wire, and coated steel wire, etc.

The steel wire used for prestressed concrete is made of high-quality carbon structural steel Steel wire for prestressed concrete has the advantages of high strength, good flexibility, no joints, stable and reliable quality, convenient construction, no need for cold drawing, no need for welding, etc Mainly used for prestressed steel bars in large-span roof trusses, thin web beams, large-span crane beams, bridges, poles, and sleepers Steel strands for prestressed concrete are made by twisting and heat treating several high-quality carbon structural steel wires to eliminate internal stress.

The mechanical performance indicators of prestressed concrete steel strands are maximum load, elongation, yield load, and failure rate. The experimental effect must comply with the prescribed numerical values.