Dehumidification structure of anchor head under the inclined cable

Abstract

The present invention discloses a dehumidification structure for the lower anchor head of an inclined cable, comprising a fixed-end anchor, an anchor pad and a plurality of steel strands, wherein the plurality of steel strands are installed in the fixed-end anchor, the fixed-end anchor is located in the anchor pad, one end of the cable duct is sealed with the anchor pad, and the other end is internally sealed by a seal, the fixed-end anchor and the steel strand are partially accommodated in the cable duct, the steel strand passes through the seal and extends out of the cable duct, an air duct structure is pre-buried in the fixed-end anchor and inputs dry air into the cable duct, the dry air mixes and flows with the original air in the cable duct, and then returns to the inner cavity of the outer protective cover through the gap between the pre-buried air duct structure and the fixed-end anchor and the cable duct, thereby reducing the internal environmental humidity, thereby performing anti-corrosion protection on the exposed parts of the fixed-end anchor and the steel strand. Through the above design, dry air enters from the air inlet of the lower anchor head and is discharged from the exhaust hole of the lower anchor head, the distance passed by the gas is short, the energy loss is relatively small, and the requirements for the air supply equipment are low.

Description

Technical Field

[0001] The invention relates to a stay cable, in particular to a dehumidification structure of an anchor head under the stay cable. Background Art

[0002] Cable-stayed bridges, also known as tensioned bridges, are widely used due to their large spans and elegant design. The cables, the primary load-bearing and force-transmitting structural components of cable-stayed bridges, are primarily composed of high-strength steel wire and anchoring devices. Due to their long-term exposure to the adverse external conditions of rivers, lakes, and oceans, the steel wires and anchoring components are highly susceptible to corrosion, seriously impacting the bridge's aesthetics and service life. Therefore, corrosion prevention of the cables is a crucial component of bridge engineering. Despite the implementation of numerous anti-corrosion measures with significant results, corrosion of the lower anchor heads of the cables remains severe.

[0003] To prevent corrosion, several improvements have been made to the cable structure, such as those described in Patents CN201810653704.7 and CN201910639676.8. Both of these improvements aim to achieve overall dehumidification by delivering dry air from the lower anchor head through the gap between the cable body and the jacket tube to the upper anchor head. However, from the perspective of corrosion protection for the entire cable, the lower anchor head is the most critical component.

[0004] Problems with the cable-stayed cable in the patent with application number CN201810653704.7: Since the anchoring devices, anchor pads and bolts used for connection at both ends of the cable are made of metal materials, they are easily corroded if they are in a humid environment for a long time. In the above-mentioned steel strand cable-stayed cable, since the anchoring device is exposed to the cable body, the anchoring device still has the problem of easy corrosion. The anchoring device is a key component for achieving fixed connection between the cable body and the bridge deck and tower. The easy corrosion of the anchoring device can easily lead to the problem of unstable connection between the cable body and the bridge deck and tower.

[0005] The cable-stayed system described in patent application number CN201910639676.8 presents challenges: The cable must be sealed at multiple locations, creating significant challenges in maintaining a stable seal, particularly in sealing the gap between the outer sheath of the steel strand and the PE pipe connection at the tower end. Furthermore, cable-stayed systems are typically long, and supplying air from the lower anchor and exhausting it from the upper anchor results in significant drag and energy loss along the way, placing high demands on the air supply equipment. Summary of the Invention

[0006] In order to overcome the shortcomings of the existing technology, the purpose of the present invention is to provide a dehumidification structure for the lower anchor head of the inclined cable, which can prevent corrosion of the inclined cable and the lower anchor head, has a simple structure, is easy to seal at various locations, saves energy, and has low equipment requirements.

[0007] The purpose of the present invention is achieved by the following technical solutions:

[0008] A dehumidification structure for the anchor head of a cable-stayed cable, comprising a fixed-end anchor, an anchor pad and several steel strands, several of the steel strands being installed in the fixed-end anchor, the fixed-end anchor being located in the anchor pad, the dehumidification structure for the anchor head of the cable-stayed cable further comprising a cable duct, a seal and an air duct structure, one end of the cable duct being sealed with the anchor pad, and the other end being internally sealed by the seal, the fixed-end anchor and the steel strands being partially accommodated in the cable duct, the steel strands extending from the cable duct through the seal, the air duct structure being pre-buried in the fixed-end anchor and inputting dry air into the cable duct, the dry air being mixed with the original air in the cable duct and then flowing back to the inner cavity of the outer protective cover from the pre-buried air duct structure and the gap between the fixed-end anchor and the cable duct, thereby reducing the internal environmental humidity, thereby performing corrosion protection on the exposed parts of the fixed-end anchor and the steel strands.

[0009] Furthermore, the anchor plate is provided with an air hole, the interior of the cable duct is connected to the exterior of the cable duct through the air hole, a gap exists between the fixed end anchor and the cable duct, and the return air flows out of the cable duct from the air hole through the gap.

[0010] Furthermore, the dehumidification structure of the anchor head under the inclined cable includes an air duct structure, and the air duct structure includes a return air duct. The return air duct is pre-buried in the fixed end anchor, and the return dry air flows out of the cable duct from the return air duct.

[0011] Furthermore, the air duct structure further includes an air supply pipe, which is pre-buried in the fixed end anchor and transports dry air into the cable duct.

[0012] Furthermore, the dehumidification structure of the anchor head under the inclined cable also includes an inner protective cover, the fixed end anchor is connected to the inner protective cover, and the end of the steel strand is accommodated in the inner protective cover.

[0013] Furthermore, two through holes are provided at the end of the inner protective cover, and one end of the return air duct and the supply air duct passes through the through holes, and the other end extends into the cable duct.

[0014] Furthermore, the dehumidification structure of the anchor head under the inclined cable also includes an outer protective cover, the outer protective cover is sealed to the anchor plate, and the inner protective cover is located in the outer protective cover.

[0015] Furthermore, the outer protective cover is provided with an exhaust hole, there is a gap between the outer protective cover and the inner protective cover, the anchor plate is provided with an air hole, the interior of the cable duct is connected with the outside of the cable duct through the air hole, and there is a gap between the fixed end anchor and the cable duct, and the return dry air flows out of the cable duct from the air hole through the gap, and flows through the gap to the exhaust hole for discharge.

[0016] Furthermore, the air duct structure also includes an air supply hose, the outer protective cover is provided with an air inlet hole, one end of the air supply hose is connected to the air inlet hole, and the other end is connected to the air supply duct.

[0017] Furthermore, the dehumidification structure of the anchor head under the inclined cable also includes a shock absorber. The sealing member is a rubber sheet and there are two of them. The two rubber sheets are respectively located on both sides of the shock absorber. The outer edge of each rubber sheet is sealed with the inner wall of the cable guide tube, and the inner edge is sealed with the outer wall of the steel strand. The steel strand passes through the rubber sheet and the shock absorber.

[0018] Compared with the prior art, the steel strand of the dehumidification structure of the lower anchor head of the inclined cable of the present invention is installed in the fixed-end anchor, and the fixed-end anchor is located in the anchor pad. The dehumidification structure of the lower anchor head of the inclined cable also includes a cable duct, a seal and an air duct structure. One end of the cable duct is sealed with the anchor pad, and the other end is internally sealed by the seal. The fixed-end anchor and the steel strand are partially accommodated in the cable duct, and the steel strand extends from the cable duct through the seal. The air duct structure is pre-buried in the fixed-end anchor and inputs dry air into the cable duct. The dry air mixes and flows with the original air in the cable duct, and the exposed parts of the fixed-end anchor and the steel strand are dried and then flow out from the cable duct. Through the above design, the dry air enters from the air inlet of the lower anchor head and is discharged from the exhaust hole of the lower anchor head. The distance passed by the gas is short, the energy loss is relatively small, and the requirements for the air supply equipment are low. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A structural schematic diagram of the dehumidification structure of the anchor head under the inclined cable of the present invention;

[0020] Figure 2 for Figure 1 Schematic diagram of airflow dehumidification structure under the anchor head of the inclined cable;

[0021] Figure 3 for Figure 1 Schematic diagram of the structure of the outer protective cover of the dehumidification structure of the anchor head under the inclined cable;

[0022] Figure 4 for Figure 1 Schematic diagram of the structure of the inner protective cover of the dehumidification structure under the anchor head of the inclined cable.

[0023] In the figure: 10, outer protective cover; 11, air inlet; 12, exhaust hole; 13, air supply pipe connector; 14, exhaust pipe connector; 21, fixed end anchor; 22, anchor plate; 30, air cavity; 40, cable guide tube; 50, steel strand; 60, inner protective cover; 61, through hole; 70, seal; 80, shock absorber; 90, air duct structure; 91, air supply hose; 92, air supply pipe; 93, return air duct. DETAILED DESCRIPTION

[0024] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0025] It should be noted that when a component is referred to as being "fixed to" another component, it may be directly on the other component or there may be another intermediate component through which it is fixed. When a component is considered to be "connected to" another component, it may be directly connected to the other component or there may be another intermediate component at the same time. When a component is considered to be "set on" another component, it may be directly set on the other component or there may be another intermediate component at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used in this specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0027] See also Figures 1 to 4 The dehumidification structure of the anchor head under the inclined cable of the present invention includes an outer protective cover 10, a fixed end anchor 21, an anchor pad 22, a cable guide tube 40, a steel strand 50, an inner protective cover 60, a seal 70, a shock absorber 80 and an air duct structure 90.

[0028] The outer protective cover 10 is equipped with an air inlet 11, an exhaust hole 12, an air supply pipe connector 13, and an exhaust pipe connector 14. The air inlet 11 and exhaust hole 12 are located at the ends of the outer protective cover 10 and on the same side. The air supply pipe connector 13 is a steel pipe with external threads that can be connected to the air supply pipe of the dehumidification equipment. The air supply pipe connector 13 is welded to the air inlet 11 and supplies dry air to the dehumidification structure of the lower anchor head of the inclined cable. The exhaust pipe connector 14 is a specialized pipe fitting that can be connected to a temperature and humidity sensor and a silicone constant pressure valve. The exhaust pipe connector 14 is welded to the exhaust hole 12.

[0029] The fixed end anchor 21 has two more mounting holes on the basis of the original hole system, with a diameter of 10mm-12mm. One mounting hole is used to pre-embed the air supply pipe 92, and the other mounting hole is used to pre-embed the return air pipe 93. The anchor plate 22 is provided with air holes.

[0030] The inner protective cover 60 is provided with two through holes 61, located at the ends of the inner protective cover 60 and on the same side of the inner protective cover 60. One through hole 61 is determined by the position of the pre-buried air supply duct 92 and has an inner diameter slightly larger than the outer diameter of the air supply duct 92; the other through hole 61 is determined by the position of the pre-buried air return duct 93 and has an inner diameter slightly larger than the outer diameter of the air return duct 93.

[0031] There are two seals 70. In this embodiment, the seals 70 are rubber sheets with a thickness of 1.5 mm to 2 mm. The outer diameter of the seal 70 is 5 mm larger than the inner diameter of the cable guide 40. The seals 70 are pre-machined with holes corresponding to the positions of the straightened steel strands 50. The diameter of the holes is 1 mm smaller than the diameter of the steel strands 50.

[0032] The air duct structure 90 includes an air supply hose 91, an air supply pipe 92, and an air return pipe 93. The length of the air supply hose 91 is slightly longer than the length of the outer protective cover 10. The inner diameter of the air supply pipe 92 and the air return pipe 93 is 8mm-10mm.

[0033] When assembling the dehumidification structure of the anchor head under the inclined cable, one end of the steel strand 50 is fixedly installed on the fixed end anchor 21. The supply air duct 92 and the return air duct 93 are pre-buried in the two mounting holes of the fixed end anchor 21. At this time, the supply air duct 92 and the return air duct 93 are parallel to each other. The inner protective cover 60 is sealed and connected to the fixed end anchor 21, and the ends of the supply air duct 92 and the return air duct 93 extend from the through hole 61. At this time, the fixed end anchor 21 and the steel strand 50 are partially accommodated in the inner protective cover 60. The outer protective cover 10 is sealed and connected to the anchor pad 22. The inner protective cover 60 is located inside the outer protective cover 10. The diameter of the outer protective cover 10 is larger than that of the inner protective cover 60. There is a gap between the outer protective cover 10 and the inner protective cover 60, and an air cavity 30 is formed between the inner protective cover 60 and the outer protective cover 10. The air cavity 30 is connected to the cable guide tube 40 through the air holes on the anchor pad 22. When threading the steel strands 50, the two seals 70 are threaded together in the order corresponding to the hole positions. After all the steel strands 50 are threaded, the two seals 70 are moved to the appropriate position and separated. The shock absorber 80 is inserted into the steel strands 50 and then pressed into the cable guide 40. The cable guide 40 is sealed and fixed to the anchor plate 22, with a gap between the cable guide 40 and the fixed-end anchor 21. The cable guide 40 communicates with the air cavity 30 through the air holes in the anchor plate 22.

[0034] When using the dehumidification structure for the lower anchor head of the cable-stayed cable, treated dry air enters through the air inlet 11 of the outer protective cover 10, passes through the air supply hose 91 and air supply pipe 92, and enters the cable duct 40. There, it mixes with the moist air inside the cable duct 40. After encountering the seal 70, the air flows back. Part of the mixed air flows back to the air cavity 30 through the return air pipe 93, while the remaining mixed air flows back to the air cavity 30 through the gap between the cable duct 40 and the fixed-end anchor 21, the air holes in the anchor pad 22, and the gap between the outer protective cover 10 and the inner protective cover 60. The air is then discharged through the exhaust hole 12, reducing the internal humidity and providing corrosion protection for the exposed parts of the fixed-end anchor 21 and the steel strands 50.

[0035] In this embodiment, since the gap between the fixed end anchor 21 and the cable guide tube 40 is small, the delay resistance during exhaustion is large, so the return air duct 93 is provided.

[0036] Through the above design, dry air enters from the lower anchor head air inlet 11 and is discharged from the lower anchor head exhaust hole 12. The distance the gas passes through is short, the energy loss is relatively small, and the requirements for the air supply equipment are low.

[0037] Those skilled in the art can make various other corresponding changes and deformations based on the technical solutions and concepts described above, and all of these changes and deformations should fall within the scope of protection of the claims of the present invention.

Claims

1. A dehumidification structure for an anchor head under a stay cable, comprising a fixed end anchor, an anchor pad, and a plurality of steel strands, characterized in that: The plurality of steel strands are installed on the fixed-end anchors, and the fixed-end anchors are located in the anchor pads. The dehumidification structure of the anchor head under the inclined cable further includes a cable duct, a seal and an air duct structure. One end of the cable duct is sealed with the anchor pad, and the other end is internally sealed by the seal. The fixed-end anchor and the steel strands are partially accommodated in the cable duct, and the steel strands extend from the cable duct through the seal. The air duct structure is pre-buried in the fixed-end anchor and inputs dry air into the cable duct. The dry air mixes with the original air in the cable duct and then flows back to the inner cavity of the outer protective cover through the pre-buried air duct structure and the gap between the fixed-end anchor and the cable duct, thereby reducing the internal environmental humidity, thereby providing anti-corrosion protection for the exposed parts of the fixed-end anchor and the steel strands. The anchor plate is provided with an air hole, the interior of the cable duct is connected to the exterior of the cable duct through the air hole, a gap exists between the fixed end anchor and the cable duct, and the return air flows out of the cable duct from the air hole through the gap; The dehumidification structure of the anchor head under the inclined cable includes an air duct structure, and the air duct structure includes a return air duct. The return air duct is pre-buried in the fixed end anchor, and the return dry air flows out of the cable duct from the return air duct.

2. The dehumidification structure for the anchor head of the stay cable according to claim 1, characterized in that: The air duct structure further includes an air supply pipe, which is pre-buried in the fixed end anchor and transports dry air into the cable duct.

3. The dehumidification structure for the anchor head of the stay cable according to claim 2 is characterized in that: The dehumidification structure of the anchor head under the inclined cable also includes an inner protective cover, the fixed end anchor is connected to the inner protective cover, and the end of the steel strand is accommodated in the inner protective cover.

4. The dehumidification structure for the anchor head of the stay cable according to claim 3 is characterized in that: Two through holes are provided at the end of the inner protective cover, one end of the return air duct and the supply air duct passes through the through holes, and the other end extends into the cable duct.

5. The dehumidification structure for the anchor head of the stayed cable according to claim 3 is characterized in that: The dehumidification structure of the anchor head under the inclined cable also includes an outer protective cover, which is sealed with the anchor plate, and the inner protective cover is located in the outer protective cover.

6. The dehumidification structure for the anchor head under the stay cable according to claim 5, characterized in that: The outer protective cover is provided with an exhaust hole, and there is a gap between the outer protective cover and the inner protective cover. The anchor plate is provided with an air hole, and the interior of the cable duct is connected with the outside of the cable duct through the air hole. There is a gap between the fixed end anchor and the cable duct, and the return dry air flows out of the cable duct from the air hole through the gap, and flows through the gap to the exhaust hole for discharge.

7. The dehumidification structure for the anchor head of the stay cable according to claim 5, characterized in that: The air duct structure also includes an air supply hose. The outer protective cover is provided with an air inlet hole. One end of the air supply hose is connected to the air inlet hole, and the other end is connected to the air supply duct.

8. The dehumidification structure for the anchor head of the stay cable according to claim 1, characterized in that: The dehumidification structure of the anchor head under the inclined cable also includes a shock absorber. The sealing member is a rubber sheet and there are two of them. The two rubber sheets are located on both sides of the shock absorber. The outer edge of each rubber sheet is sealed with the inner wall of the cable guide tube, and the inner edge is sealed with the outer wall of the steel strand. The steel strand passes through the rubber sheet and the shock absorber.

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