Stay cables are an integral component of modern cable-stayed bridges, among the most popular worldwide. Stay cables provide essential support and stability to the bridge deck and come in various types depending on specific applications and design specifications. In this article, we’ll examine the different types of stay wires.
Parallel Wire Cables
Parallel wire cables are the most common type of stay cable and consist of a bundle of parallel wires that have been prestressed to support the bridge deck. These are typically made of high-strength steel wires arranged similarly to the cable. Parallel wire cables can be used in single-plane or multi-plane configurations, depending on how your bridge is designed.
Fan Cables
Fan cables are stay cables comprising bundles of wires attached to one point on the bridge deck and spread out in a fan-like configuration for support.
The cables are usually secured to a pylon or tower at the top, with each wire prestressed for added strength. They’re often employed on cable-stayed bridges with just one pylon or tower.
Harp Cables
Harp cables are stay cables composed of multiple wires attached to two or more points on the bridge deck and arranged in a harp-like configuration to support the structure.
They’re usually anchored to a pylon or tower at the top, with individual wires prestressed for extra strength. Harp cables are commonly employed on cable-stayed bridges with multiple pylons or towers for various spans.
Inverted Fan Cables
Inverted fan cables are a variation of the fan cable, wherein a bundle of wires attaches to the bottom of the bridge deck and spreads out in a fan-like configuration for support.
Anchoring these cables to a pylon or tower at the top ensures secure attachment and individual wires have been prestressed for extra strength. They’re commonly used on cable-stayed bridges with one pylon or tower far from the bridge deck.
Semi-Fan Cables
Semi-fan cables are a hybrid between fan cables and parallel wire cables. These consist of bundles of wires attached to one point on the bridge deck, spreading out in fan-like patterns on one side while paralleling on the other.
At the top, these semi-fan cables anchor directly to a pylon or tower, and each wire has been prestressed for additional support. They’re typically employed on cable-stayed bridges with one pylon or tower where specific patterns must be used for optimal support on the deck.
Ribbon Cables
Ribbon cables are stay cables comprising one or multiple flat steel ribbons prestressed to support the bridge deck. Arranged in a parallel configuration, these ribbons form the cable, and its ends are secured to either a pylon or tower at the top. Ribbon cables often apply in cable-stayed bridges with one pylon or tower where specific patterns must be followed for optimal deck support.
Bottom Line
Stay cables are an integral component of cable-stayed bridges and come in various types depending on the application and design requirements. Parallel wire cables are the most common type, while fan cables, harp cables, inverted fan cables, semi-fan cables, and ribbon cables may also be utilized.