Multi-strand-anchor

I. Component Description

Circular Anchor Plate (Anchor Head): The body is a forged alloy steel component with a colored zinc-plated anti-rust finish. The face features evenly spaced conical cable holes (arranged in an outer ring and a center position), with each conical hole paired with a two-piece wedge set.
Conical Wedges: The black, cone-shaped components shown on the left; the inner surface features gripping teeth. During tensioning and subsequent retraction, the conical surface wedges tightly against the steel strand, enabling the independent anchoring of each individual strand.

II. Key Product Features

1. Structural Load-Bearing Characteristics

Concentrated Multi-Hole Anchoring: A single anchor plate anchors multiple steel strands simultaneously, concentrating the support for high-tonnage prestressing loads. Compared to distributed single-hole anchors, this offers superior structural integrity and more concentrated, efficient stress transfer.
Center + Outer Ring Hole Layout: Holes are evenly distributed around the circumference alongside a central hole, ensuring symmetrical and uniform load distribution. This prevents eccentric loading or twisting of the anchor plate during tensioning and is suitable for the simultaneous tensioning of multiple strands.
Independent Conical Hole Design: Each steel strand corresponds to a dedicated conical hole and wedge set. The anchoring status of individual strands remains independent, meaning an issue with a single wedge does not directly compromise the anchoring safety of the entire assembly.

2. Material and Corrosion Resistance

The anchor plate is made of forged alloy steel; compared to castings, it has fewer internal defects and higher compressive strength, allowing it to withstand the concentrated compressive stresses of high-tonnage tensioning. The colored zinc-plated surface resists corrosion from site humidity and rainfall.
The matching wedges undergo quenching and tempering for hardening; the toothed surface is highly hard, ensuring a secure grip on the steel strand’s outer layer. Their slip resistance and fatigue resistance meet the requirements for long-term dynamic loading in bridge applications. 

3. Construction and Compatibility Advantages

High tensioning efficiency: Allows for the simultaneous tensioning of an entire bundle of steel strands using a single jack, significantly reducing the number of steps required for staged tensioning; this makes it the preferred choice for bridge box girders and long-span prestressed components.
High versatility: Compatible with standard 15.2mm prestressing strands; the complete installation process can be carried out using standard tensioning jacks, anchor limit plates, and bearing plates.
Convenient maintenance and inspection: The engagement of each set of wedges can be inspected individually after tensioning, and subsequent re-tensioning or troubleshooting can be performed on a per-strand-hole basis.

4. Key Application Scenarios

Suitable for post-tensioned prestressed projects involving bundled steel strands—such as highway and railway bridge box girders, long-span roof beams, hydraulic dams, and large-scale basement prestressed structures—this system represents the most commonly used bundled working anchorage in the bridge and construction sectors.