High-strength prestressed steel strands are made by twisting multiple steel wires into steel wires, which are called steel strands. Steel strands are widely used as tension members, wires, reinforcing cores, prestressing materials, barrier wires, ground wires, etc., in many engineering fields such as bridges, power, water conservancy, buildings, and enclosures. So, let's learn about the construction process of high-strength prestressed steel strands!

　　I. Production of High-Strength Prestressed Steel Strands

　　High-strength prestressed steel strands are cut to the length required by the design. When constructing a bridge, add 200mm to the length required by the design, and then adjust the subsequent steel strand feed length according to the construction situation of the bridge. The allowable length error is 10mm. Cutting is done using an abrasive saw to ensure that the cut ends are flat; welding cutting methods must not be used. After cutting, take measures to tie the steel strand ends to prevent cracking. After cutting, tie the steel strands, move them into place, and make preparations with markings. Do not drag the steel strands directly during transportation. Do not cause damage or rust on the surface of the steel strands.

　　II. Threading a Bundle of Steel Strands

　　Before threading, clean the pull-out seat, support plate, or throttle hole. When tying, use a tying anchor rod to fix one end of the steel strand, and thread the other end into the corrugated pipe in order according to the number. The steel strand ends must be wrapped in a bullet-shaped form. Do not scatter the ends when threading. The same hole should be threaded completely according to the number.

　　III. Prestress Tensioning

　　After the high-strength prestressed steel strands are tensioned, tension the front flange, the top plate, the rear bottom plate, and the front two sides and the middle in sequence according to the design requirements. The prestress size is mainly based on the hydraulic pressure gauge reading, considering the elongation of the prestressing tendons.

　　How should high-strength prestressed steel strands be constructed?

　　1. Install the prestressed pipe well. Anchor plates and prestressed plastic corrugated pipes are used for corrugated pipe installation. Pay attention to the accurate positioning of the corrugated pipe during construction. Use the mold on the bridge or support as the cutting point for the steel strands and cut the steel strands one by one with an abrasive saw.

　　2. Single-end tensioning method, using a P-anchor to fix the prestressing tendon anchor end. To ensure the construction quality of the P-anchor, the raw materials are brought to the site, and a vernier caliper is used to perform dimensional matching tests. This includes testing the compression spring, compression head, and the overall steel strand after compression.

　　3. Fix the anchor end anchor plate at the nominal position according to the P-anchor design drawings, and after the P-chain anchor root and the traction abutting anchor plate are completed. One end is fixed, forming the anchor end.

　　4. Install the anchor rod. After the concrete is cast and cured, start installing the anchor rod. The jack meets the standard, and after the concrete reaches the design strength, install the jack and start the tensioning construction. Then, perform prestress tensioning construction. The next step is to seal the anchor rod. After the prestressed engineering is completed, seal the transverse reinforcement bundle. This is a high-strength prestressed steel strand for the completion of a large bridge.

　　The above is an introduction to the construction process of high-strength prestressed steel strands. If you need to learn more about related knowledge, please feel free to contact us!