POLYMER BLEND CRADLE FOR CABLE-STAYED BRIDGE

A cable-stayed bridge includes a pylon, a deck, and a cable stay. The pylon may include a passage formed therethrough. The cable-stayed bridge includes a polymer blend cradle extending through the passage of the pylon. The cable stay is coupled to the deck at each end of the cable stay and passes through the passage through the pylon via the polymer blend cradle.

TECHNICAL FIELD/FIELD OF THE DISCLOSURE

The present disclosure relates generally to structural construction components and specifically to cradles for cable stayed bridges.

BACKGROUND OF THE DISCLOSURE

Cable-stayed bridges typically include a pylon, a deck, and one or more cable stays extending between the deck and the pylon such that the deck is supported from the pylon by the cable stays. Typical cable-stayed bridges anchor the cable stays at the deck and the pylon.

SUMMARY

The present disclosure provides for a cable-stayed bridge. The cable-stayed bridge may include a pylon. The pylon may include a passage formed therethrough. The cable-stayed bridge may include a polymer blend cradle extending through the passage of the pylon. The cable-stayed bridge may include a deck. The cable-stayed bridge may include a cable stay. The cable stay may be coupled to the deck at each end of the cable stay. The cable stay may pass through the passage through the pylon via the polymer blend cradle.

DETAILED DESCRIPTION

FIG.1depicts cable-stayed bridge10. Cable-stayed bridge10may include pylon12and deck14. Deck14may be mechanically coupled to pylon12by cable stays16. In some embodiments, cable stays16may be anchored to deck14. In some embodiments cable stays16may be anchored at each end to deck14and may pass through passages18extending through pylon12.

In some such embodiments, as shown inFIG.2, each passage18may be formed by positioning polymer blend cradle100through pylon12. In an embodiment in which pylon12is formed from concrete, polymer blend cradle100may be positioned within the form for pylon12with the concrete poured and cast around polymer blend cable100.

In some embodiments, as shown inFIG.3, polymer blend cradle100may be tubular. In some embodiments, polymer blend cradle100may be arcuate in profile such that a cable stay16positioned therethrough enters and exits substantially straight from polymer blend cradle100as shown inFIG.2. Such an arrangement may, for example and without limitation, reduce stress concentration due to bending of cable stay16as cable stay16extends through polymer blend cradle100when installed to cable-stayed bridge10.

In some embodiments, polymer blend cradle100may be formed from a blended polymer material. By forming polymer blend cradle100from a selected blended polymer, the friction between cable stay16and polymer blend cradle100may be increased when compared with the friction between cable stay16and a metal cradle. Without being bound to theory, polymer blend cradle100may, for example and without limitation, deform more than a metal cradle, therefore increasing the surface area between cable stay16and polymer blend cradle100while also conforming to the outer profile of cable stay16. Additionally, forming polymer blend cradle100from a blended polymer material may, for example and without limitation, reduce manufacturing costs and reduce the likelihood that corrosion of cable stay16occurs compared to a metal cradle. For example, by forming polymer blend cradle100from a non-conductive polymer, galvanic corrosion caused by dissimilar metals in cable stay16and a metal cradle may be prevented.

In some embodiments, polymer blend cradle100may be formed from a blend of one or more of polyethylene, high-density polyethylene, polypropylene, high-stiffness grades of polypropylene, and nylon. In some embodiments, polymer blend cradle100may be formed with glass-filled, fiber-filled, mineral bead-filled, or sand-filled polymer. In some embodiments, polymer blend cradle100may be at least partially formed from carbon fiber.

In some embodiments, as shown inFIG.4, polymer blend cradle100may be circular in cross-section. In other embodiments, polymer blend cradle100may be formed such that the cross-sectional profile includes one or more friction-enhancing features.

For example,FIG.5depicts polymer blend cradle100ahaving V-shaped section101apositioned on the concave lower surface of polymer blend cradle100a. In such an embodiment, V-shaped section101amay further increase the friction between polymer blend cradle100aand cable stay16and further enhance the friction-increasing properties of the blended polymer material. In some embodiments, the interior of polymer blend cradle100amay be large enough to permit cable stay16to pass therethrough relatively unencumbered to allow for construction of cable-stayed bridge10. In some embodiments, as the weight of deck14is taken up by cable stay16, cable stay16is pulled downward into V-shaped section101a, thereby increasing the friction between polymer blend cradle100aand cable stay16.

As another example,FIG.6depicts polymer blend cradle100bhaving keyway section101bpositioned on the concave lower surface of polymer blend cradle100b. In such an embodiment, keyway section101bmay further increase the friction between polymer blend cradle100band cable stay16and further enhance the friction-increasing properties of the blended polymer material. In some embodiments, the interior of polymer blend cradle100bmay be large enough to permit cable stay16to pass therethrough relatively unencumbered to allow for construction of cable-stayed bridge10. In some embodiments, as the weight of deck14is taken up by cable stay16, cable stay16is pulled downward into keyway section101b, thereby increasing the friction between polymer blend cradle100band cable stay16.

As another example,FIG.7depicts polymer blend cradle100c. Polymer blend cradle100cmay have a cross-section that includes upper circular path101cand lower circular path103c. Upper circular path101cand lower circular path103cmay be intersecting such that upper circular path101cand lower circular path103ctogether form the interior of polymer blend cradle100c. In some embodiments, the diameter of upper circular path101cmay be large enough to permit cable stay16to pass therethrough relatively unencumbered to allow for construction of cable-stayed bridge10. In some embodiments, the diameter of lower circular path103cmay be smaller than the diameter of upper circular path101csuch that as the weight of deck14is taken up by cable stay16, cable stay16is pulled downward from upper circular path101cinto lower circular path103c, thereby increasing the friction between polymer blend cradle100cand cable stay16.