What Is PC Steel Wire?
PC steel wire is a high-strength wire used in prestressed concrete to enhance the tension properties of concrete, which is typically weak in tension. By applying compressive force during manufacturing, it significantly increases the structure’s strength, clamping concrete at high stresses of about 80% of the yield point.
Key quality parameters include high tensile strength, elongation at break, low relaxation, straightness, workability, and uniformity.
Uses of PC Steel Wires
PC steel wires, with a strength of 5 to 6 times that of regular steel bars, are used for pre-stressing concrete through pre-tensioning or post-tensioning methods. Their applications span across:
- Road and rail bridges, sleepers, tanks, and construction
- Bridge structures, building foundations, and bodies
- Containers like tanks and reservoirs
- Disaster prevention equipment like rock-sheds and snow-sheds
- Cores for telegraph poles
Special cutting machines are used for PC steel wires in emergencies.
Types of PC Steel Wires
PC steel wires are categorized based on strength and shape:
- Normal strength types: SWPR1AN, SWPR1AL, SWPD1N, SWPD1L
- High strength types: SWPR1BN, SWPR1BL
- Shapes include round wire and irregularly shaped wire. Round wires are classified as Class A or B (Class B being stronger), and deformed wires as SWPR1BN or SWPR1BL, with ‘N’ for normal relaxation and ‘L’ for low relaxation.
Standards specify nominal dimensions, cross-sectional area, mass, stress and force tests, elongation, relaxation values, and strength levels. Winding, torsional, and bending properties are also outlined.