Construction and installation method for main cable protection belt

Abstract

The invention discloses a main cable protection belt construction and installation method, relates to the technical field of bridge main cable protection, and aims to enhance the sealing performance and stability of a bridge main cable protection structure. Comprising the following steps: winding: spirally winding protective belts on a main cable, and overlapping the adjacent protective belts to form at least two layers and at most three layers; welding, wherein the protective belt is heated to be welded; sealing a circular seam, namely sealing the circular seam of the cable clamp by using a wedge-shaped rubber strip and a sealant, wrapping by using an ultraviolet-proof starting belt, and fixing by using a hoop; and anti-skid treatment: coating an anti-skid agent on the top of the protective belt. According to the construction and installation method for the main cable protection belt, the construction quality and the protection performance of the protection belt are remarkably improved, and the sealing performance and the long-term stability of a system are enhanced.

Description

Technical Field

[0001] The invention relates to a bridge main cable protection technology. Background Art

[0002] In modern bridge engineering, especially large structures such as suspension bridges and cable-stayed bridges, the main cable is a key load-bearing element, and its long-term performance and durability are crucial. In order to prevent corrosion and other environmental factors, it is usually necessary to protect the main cable. The following protection methods are mainly used in the prior art, such as traditional tape wrapping, heat shrink tubing, coating, etc. The Chinese invention patent with publication number CN107326806A discloses a rigid-flexible composite main cable protection system, which is spirally wound on the surface of the circular cross-section metal component of the main cable of the suspension bridge. The protection system includes a first layer of elastomeric isolation layer and a second layer of rigid wrapping tape; the elastomeric isolation layer is an elastomeric tape or an elastic coating, which is wrapped in overlapping laps, hot-pressed or applied on the surface of the circular cross-section metal component; the rigid wrapping is a tape prepreg or hand-laid fiber-reinforced composite material, and the rigid wrapping tape is wrapped around the outside of the elastomeric isolation layer. The elastomeric isolation layer of the present invention can be directly wrapped around the surface of the main cable steel wire of the suspension bridge to bear the deformation difference between the outer wrapping tape and the main cable due to temperature changes, wind and earthquakes, vehicles and other loads. The present invention adopts a method of wrapping a layer of rigid wrapping tape on the surface of the elastomeric isolation layer to form a set of rigid-flexible composite material protection system.

[0003] The above technical solution still has the problem of unsatisfactory protection effect: there may be gaps or poor overlap between the protection belts, which cannot form a continuous and sealed protection layer, which is easy to cause moisture and other corrosive substances to invade, shortening the service life of the main cable and affecting the overall protection effect. At the same time, the sealing treatment of important parts such as the seams of the cable clamp ring is not perfect, which can easily become the weak link of the protection system.

[0004] Any discussion of the background technology throughout the specification does not mean that the background technology is necessarily the prior art known to technicians in the relevant field; any discussion of the prior art throughout the specification does not mean that the prior art is necessarily widely known. Summary of the invention

[0005] The present invention aims to provide a main cable protection belt construction and installation method to enhance the sealing and stability of the protection structure.

[0006] The main cable protection belt construction and installation method includes the following steps:

[0007] S5. Winding: spirally wind the protective strip on the main cable, with adjacent protective strips overlapping to form a minimum of two layers and a maximum of three layers;

[0008] S6. Welding, heating the protective belt to weld it;

[0009] S7. Ring seam sealing: Use wedge-shaped rubber strips and sealant to seal the ring seam of the cable clamp, then wrap it with UV-resistant starter tape and fix it with a clamp;

[0010] S8. Anti-slip treatment: apply anti-slip agent on the top of the protective belt.

[0011] The beneficial effects are as follows:

[0012] 1. Improve the protection performance. By spirally winding adjacent protective belts to overlap to form a two-layer or three-layer structure, the main cable surface is fully protected and the ability to resist corrosion, UV rays and mechanical damage is enhanced. Heating the protective belts to an appropriate temperature ensures good welding between the protective belts, forming a continuous and sealed whole, effectively preventing the intrusion of moisture and other corrosive substances.

[0013] 2. To enhance the sealing and long-term stability, the seam of the cable clamp is sealed with a wedge-shaped rubber strip and sealant, and then wrapped with a starter belt and fixed with a stainless steel clamp. This multi-level sealing design not only provides a physical barrier, but the material of the starter belt can resist ultraviolet aging, further extending the service life of the protection system. The start and end of the protection belt are embedded in the groove of the cable clamp to avoid the joint being exposed to the outside and reduce the risk of damage caused by external factors.

[0014] In summary, the main cable protection belt construction and installation method of the present invention not only significantly improves the construction quality and protection performance of the protection belt, but also enhances the sealing and long-term stability of the system. These improvements make the method have important practical application value and development prospects in large bridge construction.

[0015] Furthermore, when wrapping the tape in S1 begins, the end of the protective tape is located on the side of the main cable and faces downward, and the wrapping direction is uniformly from the inside of the main cable to the outside of the main cable.

[0016] Furthermore, when the tape is continued in S1, a new tape is inserted from bottom to top into the gap of the already tape-wrapped portion.

[0017] Furthermore, in S1, the belt is wrapped from the low-position cable clamp to the high-position cable clamp, and the higher protection belt is overlapped and pressed on the outer surface of the lower protection belt.

[0018] Furthermore, each heating cycle in S2 lasts for 5 to 7 minutes, the temperature is 125 ± 5°C, the heating is timed for 2 to 4 minutes, and the heating tube is rotated 1 / 4 turn before heating for another cycle.

[0019] Furthermore, the starting end and the ending end of the protective belt winding in S3 are embedded in the cable clamp groove.

[0020] Furthermore, the joints of the wedge-shaped rubber strip in S3 are located on the left and right sides. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a cross-sectional schematic diagram of the main cable protection structure in an embodiment of the present invention.

[0022] Figure 2 Schematic cross-sectional view of the multi-layer overlapping structure after the main cable protection belt is wrapped in the embodiment. DETAILED DESCRIPTION

[0023] The present invention is further described in detail below through specific embodiments:

[0024] The reference numerals in the drawings of the specification include: main cable 1, cable clamp 2, sealant 3, wedge-shaped sealing strip 4, stainless steel clamp 5, starting belt 6, protective belt 7, winding steel wire 8.

[0025] The main cable protection belt construction and installation method uses materials such as protection belt, starting belt, wedge-shaped rubber strip, sealant, stainless steel clamp, belt wrapping machine, heating blanket, etc. The protection belt is a 1.2m thick modified aminosulfonated polyethylene rubber laminated product. It is a three-layer structure sheet composed of CSM rubber membrane, polyester fiber and CSM rubber membrane. It has a 9x9 grid-shaped reinforced polymer to ensure the stability of the system space. The completed main cable protection structure is as follows Figure 1 shown.

[0026] To install the cover strip:

[0027] 0. Preparation: Before the construction of the protective belt, the main cable needs to be wrapped with wire. The wire wrapping tension must meet the design requirements. The wire wrapping surface must be kept flat and arranged tightly. The welding points on the wire wrapping need to be polished and smooth. There should be no bulges in the wire in the groove of the cable clamp ring seam.

[0028] 1. Winding: First, start the protective tape, then install it on the tape wrapping machine, and finally use the tape wrapping machine to wrap it. During the winding process, multiple layers of coverage are formed. The stacking area must be ≥52% and as close to 52% as possible, forming a two-layer or three-layer protective layer. The spiral stacking method covers the surface of the steel cable with two layers of protective tape. The thickness of the two layers is 2.4mm, and the thickness of the overlapping part is 3.6mm when it is 3 layers. When a roll of tape is used up, a new roll of tape is connected according to the specifications. When winding, ensure that the spacing between each circle is equal.

[0029] The structure after winding is as follows Figure 2 As shown, d1 is the overlapping width of the three layers, d2 is the seam spacing, and d3 is the protection strip width.

[0030] Other points:

[0031] At the beginning of wrapping, the end of the protective tape is located on the side of the main cable and facing downwards. The winding direction is uniformly from the inside of the main cable to the outside of the main cable. The inter-winding joint should be arranged at the 3 o'clock position on the outside of the main cable. Uniform spacing and sufficient tension need to be maintained during the winding process. The evaluation standard of the winding tension is that the index finger cannot be smoothly inserted between two adjacent layers of wrapping tape.

[0032] At the tape continuation part, the new tape is inserted from bottom to top into the gap of the already taped part, and the overlapping length of the two is ≥50mm.

[0033] The belt is wrapped from the low-position cable clamp to the high-position cable clamp. When the two sections of the protection belt overlap at the intersection, the higher protection belt is pressed on the outer surface of the lower protection belt. The starting and ending points of the belt wrapping between every two cable clamps are manually wrapped.

[0034] 2. Heating: Use a heating blanket to evenly heat the protective belt to make it welded. Each heating cycle is 6 minutes in total. Heat for 3 minutes at a time. Rotate the heating tube 1 / 4 turn: heat for 6 minutes, move to the next position and heat according to the above steps. The temperature is 125±5℃.

[0035] Other points:

[0036] During the welding process of the protective strip, the forward movement distance of the heating should not be too large. Multiple sets of heating blankets can be operated at the same time, but the opening directions must be staggered, and the front-to-back distance between two adjacent ones should be an integer multiple of 700mm.

[0037] 3. Ring seam sealing: Apply a circle of sealing silicone glue on the ring seam of the cable clamp, with brand ≥800; then install a circle of wedge-shaped rubber strip on the outer ring of the protective belt in the adjacent place, and knock it into the ring seam with a wooden hammer to make the wedge-shaped rubber strip and the sealant bite; a layer of UV-proof starting belt should be added outside the wedge-shaped rubber strip. The starting belt is a chlorosulfonated polyethylene (CSM) rubber film with a thickness of 0.7±0.5mm. Since the rubber strip is wedge-shaped, it is also conical after adding the starting belt. Finally, a stainless steel clamp is used to fix the end with a larger outer diameter of the starting belt. The starting belt shrinks and wraps the wedge-shaped rubber strip, and the end of the starting belt forms a bonding seal with the wrapping belt.

[0038] Other points:

[0039] The starting and ending ends of the protective belt wrap need to be embedded in the grooves of the cable clamp, the cable clamp ring seam is fully filled with sealant, a wedge-shaped rubber strip is installed at the ring seam, and the end face of the wedge-shaped rubber strip and the end face of the cable clamp are bonded and sealed with sealant.

[0040] The joints of the wedge-shaped rubber strip are located on the left and right sides, not on the top and bottom.

[0041] 4. Anti-slip layer of the main cable walkway: Anti-slip agent needs to be applied on the top of the protective belt. The method is: apply a 300m wide glue tape on the top of the main cable, and then sprinkle a layer of quartz sand on the glue tape for anti-slip. Figure 2 The dotted line on the upper left edge is the anti-slip coating.

[0042] 5. Inspection: If the steel cable needs to be inspected during use, a piece of protective tape can be cut off, and then only a new tape and a wind tube are needed to repair it.

[0043] The above is only an embodiment of the present invention. For those skilled in the art, several modifications and improvements can be made without departing from the scheme of the present invention, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The protection scope required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. The main cable protection belt construction and installation method is characterized by: The following steps are involved: S1. Winding: spirally wind the protective strip on the main cable, with adjacent protective strips overlapping to form a minimum of two layers and a maximum of three layers; S2. Welding, heating the protective belt to make it welded; S3. Ring seam sealing: Use wedge-shaped rubber strips and sealant to seal the ring seam of the cable clamp, then wrap it with UV-resistant starter tape and fix it with a clamp; S4. Anti-slip treatment: apply anti-slip agent on the top of the protective belt.

2. The main cable protection belt construction and installation method according to claim 1 is characterized in that: When the tape wrapping in step S1 starts, the end of the protective tape is located on the side of the main cable and faces downward, and the wrapping direction is uniformly from the inside of the main cable to the outside of the main cable.

3. The main cable protection belt construction and installation method according to claim 2 is characterized in that: When the tape is continued in S1, the new tape is inserted into the gap of the already tape-wound part from bottom to top.

4. The main cable protection belt construction and installation method according to claim 3 is characterized in that: In S1, the belt is wrapped from the low-position cable clamp to the high-position cable clamp, and the higher protection belt overlaps and presses on the outer surface of the lower protection belt.

5. The main cable protection belt construction and installation method according to claim 4 is characterized in that: Each heating cycle in S2 is 5 to 7 minutes in total, the temperature is 125 ± 5°C, the heating is timed for 2 to 4 minutes, and the heating tube is rotated 1 / 4 turn before heating for another cycle.

6. The main cable protection belt construction and installation method according to claim 5 is characterized in that: The starting end and the ending end of the protective belt winding in S3 are embedded in the cable clamp groove.

7. The main cable protection belt construction and installation method according to claim 6 is characterized in that: The joints of the wedge-shaped rubber strips in S3 are located on the left and right sides.

Images