Prestressed steel strand is 3,7, or 19 high-strength steel wire composed of twisted steel cable, and after the elimination of stress treatment (stabilization treatment) for prestressed concrete or similar purposes.
The main characteristics of prestressed steel strand and relaxation properties of high strength is good, other than the upright when expanded. Common tensile strength rating of 1860 MPa, as well as 1720,1770,1960,2000,2100 MPa strength grade of the class.
All countries have a standard for pre-stressed strand, such as: China Standard GB / T 5224, American Standard ASTM A416, British Standard BS 5896 and the Japanese standard JIS G3536, Australia and New Zealand Standard AS / NZS 4672, the Brazilian Standard NBR-7483
In most post-tensioning and pre-tensioned prestressed engineering, smooth strand is the most widely used in prestressed steel. Die pulling strand is mainly used for upgrading works, but also in the category of nuclear power projects. Galvanized steel strand tied commonly used in the bridge, cables, and external prestressing works. The use of epoxy coated and galvanized steel strand prestressed strand is similar.
5.Categories In accordance with a strand of steel wire strand number can be divided into two, three wire strand, 7-wire strand and 19 strand wire. In accordance with the surface morphology can be divided into smooth strand strand nicks, mode pulling strand (compact), galvanized steel strand, epoxy coated strand and so on. You can also according to diameter, or intensity level, or standard classification.
6.Manufacturing methods High-carbon steel wire rod, after a surface treatment after the cold drawing into wire, and then structure a certain amount of steel wire strand twisted synthetic stock, and then through the elimination of the stabilization process of stress made. To extend the durability, wires can have metal or non-metallic coating or coating, such as galvanized, coated epoxy resins. To increase the bond strength with concrete, the surface could have scored and so on. Die pull of the prestressed steel strand in the strand through a die after the compression process, the structure is more compact, more suitable anchor grip surface. Production of strand (unbonded steel strand) the ordinary pre-stressed strand coated anti-corrosion grease or wax after the package of high-density polyethylene (HDPE) to become.