Construction and a tension element comprising a cable and a plurality of strakes

Patent metadata

Field	Value
Publication number	US-9476172-B2
Application number	US-201314409790-A
Country	US
Kind code	B2
Filing date	Jun 28, 2013
Priority date	Jun 28, 2012
Publication date	Oct 25, 2016
Grant date	Oct 25, 2016

Abstract

The invention provides a construction comprising a structural element and at least one cable ( 100 ) arranged in tension to carry at least a part of the weight of the structural element. The cable defines an outer surface ( 102 ) onto which a plurality of strakes ( 104 ) form protrusions for reducing rain and wind induced vibrations. Each strake has a height being a distance from a strake root part connected to the outer surface of the cable and a strake end part terminating the strake outwards form the cable, a width being transverse to the height, and a length transverse to the height and width and along which length the strake is connected to the cable. The length of each strake is shorter than the circumference of the outer surface, and the height is less than 5 percent of the diameter of the cable.

First claim

The invention claimed is:

1. A construction comprising a structural element and at least one cable arranged in tension to carry at least a part of the weight of the structural element, the cable defining an outer surface onto which a plurality of strakes form protrusions for reducing rain and wind induced vibrations, wherein each strake has a height being a distance from a strake root part connected to the outer surface of the cable and a strake end part terminating the strake outwards form the cable, a width being transverse to the height, and a length transverse to the height and width and along which length the strake is connected to the cable, the length of each strake being shorter than the circumference of the outer surface, wherein the height is less than 5 percent of the diameter of the cable, and wherein the longitudinal direction of the strake extends in a direction substantially orthogonal to the longitudinal direction of the outer surface.

2. A construction according to claim 1 , wherein the length of each strake is less than half of the circumference of the outer surface.

3. A construction according to claim 1 , wherein the cable defines a plurality of first cross-sections along which no strakes are defined, and a plurality of second cross-sections along which one or more strakes are defined.

4. A construction according to claim 1 , wherein a plurality of strakes are arranged to form a predetermined pattern on the outer surface of the cable.

5. A construction according to claim 4 , wherein the plurality of strakes is arranged to form a helical pattern along the outer surface of the cable.

6. A construction according to claim 4 , wherein the plurality of strakes is arranged to form a periodic pattern along the outer surface of the sheath.

7. A construction according to claim 4 , wherein each strake extends in a direction transverse to the predetermined pattern.

8. A construction according to claim 7 , wherein the cable comprises at least one strand housed in a sheath which defines the outer surface of the cable.

9. A construction according to claim 1 , wherein the outer surface is substantially smooth.

10. A tension element for carrying at least a part of a structural element, the tension element comprising a cable and a plurality of strakes, the cable defining an outer surface onto which the plurality of strakes form protrusions for reducing rain and wind induced vibrations, wherein each strake has a height being a distance from a strake root part connected to the outer surface of the cable and a strake end part terminating the strake outwards form the cable, a width being transverse to the height, and a length transverse to the height and width and along which length the strake is connected to the cable, the length of each strake being shorter than the circumference of the outer surface, wherein the height is less than 5 percent of the diameter of the cable, and wherein the longitudinal direction of the strakes extends in a direction substantially orthogonal to the longitudinal direction of the outer surface.

11. A method for reducing rain and wind induced vibrations in a cable which carries at least a part of the weight of a structural element in a construction, the method comprising the steps of:
providing a plurality of stakes, each having a length being shorter than the circumference of the cable;
arranging the strakes so that the longitudinal direction of the strakes extends in a direction substantially orthogonal to the longitudinal direction of the cable, and
connecting the plurality of strakes to an outer surface of the cable,
wherein a height of the at least one strake is less than 5 percent of the diameter of the cable.

Assignees

• Univ Danmarks Tekniske

Inventors

• Georgakis Christos Thomas
• Kleissl Kenneth

Classifications

• E01D11/04

  Cable-stayed bridges · CPC title

• E01D11/02

  Suspension bridges · CPC title

• F15D1/004

  oriented essentially parallel to the direction of flow · CPC title

• E01D11/00 Primary

  Suspension or cable-stayed bridges · CPC title

• F15D1/10

  around bodies of solid material · CPC title