A main cable protection structure construction method using fireproof felt tape

Abstract

The present invention relates to a method for constructing a main cable protection structure using a fireproof felt tape, and the specific steps are as follows: Step 1: Cleaning the main cable surface; Step 2: Construction of a double-layer fireproof protective layer; Step 3: Construction of a sealing protective layer; Step 4: Construction of a coating layer. By changing at least one layer of the traditional butt-bundled aerogel felt fireproof protective layer into a spirally wound fireproof protective layer, it is ensured that at least one complete and continuous winding surface is formed, so that the bonding between the two fireproof protective layers is tighter and more complete, which greatly alleviates the problem of the fireproof protective layer at high places being easy to slide down. At the same time, by using a fireproof felt tape of aerogel felt (including self-adhesive type), not only the bonding force between the aerogel felt and the main cable surface is directly improved, and the flatness of the construction is improved, but also the construction is convenient, and the construction efficiency is greatly improved. The aerogel felt material is built into the flame-retardant coating cloth, which can effectively solve the problem of powdering of the aerogel felt material during the main cable protection construction process, and is more environmentally friendly.

Description

Technical Field

[0001] The invention relates to the technical field of fire protection of main cables of suspension bridges, and in particular to a main cable protection structure construction method using fireproof felt belts. Background Art

[0002] As the main component material of long-span bridge cables, high-strength steel wires have a large thermal conductivity. Under high temperatures of fire, they will heat up rapidly with the increase of ambient temperature, and their mechanical properties will also decrease. Therefore, correctly evaluating the mechanical properties of high-strength steel wires under high temperatures of fire is the basis for studying the high-temperature mechanical properties of main cables of suspension bridges.

[0003] The existing fire protection measures for bridge main cables are mainly based on coating fire retardant coatings or single-layer fire retardant coating materials. However, these measures have limitations such as limited protection effect and insufficient durability. Aerogel felt, as a new type of high-efficiency thermal insulation material, has excellent fire resistance and has been gradually used in the protection of bridge main cables.

[0004] In the construction method of using double-layer aerogel felt as the fire-resistant and heat-insulating layer of the main cable, since the aerogel felt has a high degree of hydrophobicity, low surface energy and good chemical stability, its adhesion to various types of glue is weak, so it is usually tied and fixed with cable ties outside the aerogel felt layer. However, the main cable of the suspension bridge has a large span and is approximately parabolic in shape. As time goes by, the aerogel felt tied and fixed at a high place will gradually slide down due to its own weight and the vibration of the bridge structure. Because both layers of aerogel felt are tied and fixed, the sliding of the outer layer of aerogel felt exacerbates the sliding of the inner layer of aerogel felt. Therefore, the aerogel felt at a higher height gradually accumulates towards the main cable position at a lower height, affecting the fireproof structure of the entire main cable.

[0005] In addition, when using a wrapping machine to construct the outer wrapping tape, there is a risk that the wrapping machine will squeeze and damage the aerogel felt, which not only weakens the fireproof effect, but also causes a large area of ​​the aerogel felt to fall off, causing certain pollution and harming human health. Summary of the invention

[0006] Aiming at the problem that the double-layer aerogel felt fire-resistant layer in the prior art is fixed with tie bands, which causes it to gradually slide down in the long term, the present invention provides a main cable protection structure construction method using fire-resistant felt tape, and the specific steps are as follows:

[0007] Step 1: Clean the surface of the main cable;

[0008] Step 2: Double-layer fire protection layer construction

[0009] The first fire-resistant protective layer and the second fire-resistant protective layer are sequentially arranged on the surface of the main cable, and are constructed by a combination of coating and spiral winding or a spiral winding method;

[0010] Step 3: Construction of sealing protective layer

[0011] Firstly, a layer of flame retardant sealant is scraped on the second fireproof protective layer, and then a layer of bundle-shaped heat-insulating special fiber cloth is wrapped around it; then, a layer of flame retardant sealant is scraped on the second fireproof protective layer, and then a layer of bundle-shaped heat-insulating special fiber cloth is wrapped around it;

[0012] Step 4: Coating application

[0013] A flexible fluorocarbon topcoat is applied on the dried sealing protective layer on the outer surface.

[0014] Furthermore, in the combined method of coating and spiral winding in step 2, the first fire-resistant protective layer is coated with a flame-retardant fire-resistant felt material on the surface of the main cable by butt coating and fixing with a fire-resistant cable tie, and then a water-based EVA adhesive is applied thereon, and the second fire-resistant protective layer thereon is continuously and evenly wrapped with a fire-resistant felt tape, and the two adjacent circles of the fire-resistant felt tape are tightly fitted; the outside of the second fire-resistant protective layer is fixed with a fire-resistant cable tie.

[0015] Furthermore, the fireproof felt belt comprises the fire-resistant layer and the outer covering layer; the fire-resistant layer is accommodated between two layers of the outer covering layer, and the edges of each layer are fixed by pressing; the fire-resistant layer is composed of a single layer or multiple layers of fire-resistant material; the outer covering layer is a flame-retardant covering cloth.

[0016] Furthermore, the fire-resistant layer is composed of a single layer or multiple layers of aerogel felt; the outer covering layer is made of one of double-sided glass fiber cloth, aluminum foil cloth, and high silica cloth, and the gap between the cloth surfaces of the outer covering layer is smaller than the size of the aerogel felt particles.

[0017] Furthermore, in the spiral winding method in step 2, the first fire-resistant protective layer and the second fire-resistant protective layer are both continuously and evenly wound with self-adhesive fireproof felt tape, the two adjacent circles of the self-adhesive fireproof felt tape are tightly fitted, and the second fire-resistant protective layer is fixed with a fire-resistant cable tie.

[0018] Furthermore, the self-adhesive fireproof felt tape comprises the fireproof felt tape and an adhesive layer, and the adhesive layer is arranged on or below the outer covering layer.

[0019] Furthermore, the adhesive layer 8 is a double-sided adhesive colloid.

[0020] Furthermore, the adhesive layer 8 is a butyl tape with a thickness greater than or equal to 1 mm, the width of the adhesive layer is smaller than the width of the outer covering layer, and the distance between a single-side edge of the adhesive layer and an edge of the outer covering layer on the same side is greater than 8 mm.

[0021] Furthermore, the fire-resistant cable ties are 304 stainless steel cable ties with a size of 0.25 mm×10 mm, and are fastened by bundling every 8 to 12 cm.

[0022] Furthermore, the total thickness of the flame retardant vulcanized rubber sealant in step 3 is 3000 μm; and the thickness of the flexible fluorocarbon topcoat in step 4 is 40 μm.

[0023] Compared with the prior art, the invention has the following beneficial effects:

[0024] By replacing at least one layer of the traditional butt-bundled aerogel felt fire-resistant protective layer with a spirally wound fire-resistant protective layer, it is ensured that at least one complete and continuous winding surface is formed, making the bonding between the two layers of fire-resistant protective layers tighter and more complete, greatly alleviating the problem of the fire-resistant protective layer at high places being easy to slide down. At the same time, by using aerogel felt (including self-adhesive) fireproof felt tape, not only the bonding force between the aerogel felt and the main cable surface is directly improved, the smoothness of the construction is improved, but also the construction is convenient, and the construction efficiency is greatly improved. The aerogel felt material is built into the flame-retardant coating cloth, which can effectively solve the problem of aerogel felt material powdering during the main cable protection construction process, and is more environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A flow chart of a main cable protection structure construction method using a fireproof felt tape according to the present invention;

[0026] Figure 2 A schematic diagram of a main cable protection structure using a fireproof felt belt according to the present invention;

[0027] Figure 3 A schematic diagram of a fireproof felt belt in an embodiment of the present invention;

[0028] Figure 4 This is a schematic diagram of the structural layers of the fireproof felt belt in Example 1 of the present invention;

[0029] Figure 5 This is a schematic diagram of the structural layer of the self-adhesive fireproof felt tape in Example 2 of the present invention;

[0030] Figure 6 It is a schematic diagram of the sewing edge pressing form in the present invention;

[0031] Figure 7 It is a schematic diagram of the nailing and edge pressing form in the present invention;

[0032] In the figure: 1. Main cable surface; 2. First fire resistant protective layer; 3. Second fire resistant protective layer; 4. Sealing protective layer; 5. Coating layer; 6. Fire resistant layer; 7. Outer covering layer; 8. Adhesive layer; 9. Edge pressing part. DETAILED DESCRIPTION

[0033] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. 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 creative work should fall within the scope of protection of the present invention.

[0034] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. The orientation or position relationship indicated by the terms "upper", "lower", "front", "back", "top", "bottom", etc. is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or part referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. It should be understood that the data used in this way can be interchanged where appropriate, so as to describe the embodiments of the present invention described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.

[0035] In order to solve the problem that the double-layer aerogel felt fire-resistant layer in the prior art is fixed with cable ties during construction, which causes it to gradually slide down over a long period of time, the outer fire-resistant protective layer is wrapped on the inner fire-resistant protective layer by a spiral wrapping construction method, so that the structure of the two fire-resistant protective layers is tighter and more stable, and the overall fire-resistant structural property of the bridge is better.

[0036] like Figure 1 As shown, a construction method of a main cable protection structure using a fireproof felt tape, the specific steps are as follows:

[0037] Step 1: Clean the main cable surface 1 to ensure there is no oil stain, water stain or other debris attached;

[0038] Step 2: Double-layer fire protection layer construction

[0039] The first fire-resistant protective layer 2 and the second fire-resistant protective layer 3 are sequentially arranged on the main cable surface 1, and the construction is carried out by using a combination of coating and spiral winding or a spiral winding method;

[0040] Step 3: Construction of sealing protective layer 4

[0041] A sealing protection system of 2 glues and 2 cloths is adopted. First, a layer of flame retardant sealant is scraped on the second fire protection layer 3, and a layer of fiber cloth for bundle-shaped heat insulation is wrapped; then a layer of flame retardant sealant is applied, and a layer of fiber cloth for bundle-shaped heat insulation is wrapped. The flame retardant sealant is a flame retardant vulcanized rubber sealant. When applying the sealant, ensure that the thickness of the applied colloid is uniform without omissions, and when wrapping the fiber cloth for bundle-shaped heat insulation, ensure that the wrapping force is uniform without bulging. The total thickness of the sealing layer is 3000μm.

[0042] Step 4: Coating layer 5 application

[0043] Two coats of 40μm flexible fluorocarbon topcoat are applied on the dried sealing protective layer 4 on the outer surface. To further ensure the beauty of the construction effect, the coating color is consistent with the original design of the main cable.

[0044] Example 1

[0045] The combination of coating and spiral winding in step 2 is that the first fire-resistant protective layer 2 is butt-coated and fixed with fire-resistant cable ties, and the flame-retardant fire-resistant felt is coated on the main cable surface 1. Before formal construction, the size of the flame-retardant fire-resistant felt is determined according to the size of the main cable. The length of each piece of flame-retardant fire-resistant felt is the length of the main cable at the corresponding position, and the width is the circumference of the circular cross-section of the section of the main cable, so as to ensure that the section of the main cable is just butt-coated with a layer of flame-retardant fire-resistant felt. The size must be accurate and the edges must be neat during cutting to ensure that there are no excessive gaps during coating. During construction, first, a double-sided tape is added every 30 cm on the surface of the main cable to preliminarily fix the first fire-resistant protective layer 2 to prevent it from sliding. Then the cut single piece of flame-retardant fire-resistant felt is butt-coated and covered on the surface of the main cable, and fixed with a fire-resistant cable tie until the flame-retardant fire-resistant felt is evenly covered on the surface of the main cable 1 in turn to form the first fire-resistant protective layer 2. Then apply 1-2mm water-based EVA adhesive, and the second fire-resistant protective layer 3 on it is continuously and evenly staggered with fire-resistant felt tape. After each circle of winding, it is compacted in the direction of the previous circle, and the adjacent two circles of fire-resistant felt tape are tightly fitted. In order to better fix, the winding part outside the second fire-resistant protective layer 3 is fixed with a fire-resistant cable tie.

[0046] like Figure 3 As shown, the fireproof felt tape is a long strip roll, and its width and thickness can be customized according to project needs.

[0047] like Figure 4 As shown, the fireproof felt belt includes the fireproof layer 6 and the outer covering layer 7; the fireproof layer 6 is accommodated between two layers of the outer covering layer 7, and the edges of each layer are fixed by pressing; the fireproof layer 6 is composed of a single layer or multiple layers of fireproof material; the outer covering layer 7 is a flame-retardant covering cloth.

[0048] In order to better fix the fireproof layer 6 in the outer covering layer 7, the self-adhesive fireproof felt tape is fixed by pressing the edges on both sides in the length direction. A variety of fixing methods can be used, such as Figure 4 , Figure 6 and Figure 7 As shown in the edge pressing part 9. Figure 6 As shown, the edge pressing method adopts sewing thread to fix (stitching fix). At the same time, in order to further improve the fire prevention effect, the sewing thread is a fireproof line. Figure 7 As shown, the edge pressing method adopts stapling. The principle of stapling is similar to that of staple binding, and the fire-resistant layer 6 and the outer covering layer 7 are fixed together using a thin metal nail or other material similar to a staple, and the nail passes through the cloth and is bent at the back to keep the two layers connected.

[0049] The fire-resistant layer 6 is composed of a single layer or multiple layers of aerogel felt. The outer layer 7 is made of one of double-sided glass fiber cloth, aluminum foil cloth, and high silica cloth. These materials are resistant to high temperatures and have certain flame retardancy and chemical resistance, which can improve the overall fire resistance of the structure. The gap between the outer layer 7 is smaller than the size of the aerogel felt particles to ensure that the powder of the aerogel felt will not leak out.

[0050] The fire-resistant cable ties are 304 stainless steel cable ties with a size of 0.25mm×10mm, and are tied together every 8 to 12cm for fixation.

[0051] By using spiral winding of fireproof felt tape as the construction method of the second fireproof protective layer, a complete and continuous winding surface is formed outside the first fireproof protective layer, which improves the bonding effect between the two fireproof layers to a certain extent. Compared with the two-layer coating and docking binding construction method, it alleviates the problem of the high-altitude fireproof protective layer being easy to slide down to a certain extent. At the same time, by embedding the aerogel felt material into the flame-retardant coating cloth, the problem of aerogel felt material powdering during the main cable protection construction process can be effectively solved, which is more environmentally friendly.

[0052] Example 2

[0053] The spiral winding method in step 2 is that the first fire-resistant protective layer 2 and the second fire-resistant protective layer 3 are both continuously and evenly wound with self-adhesive fireproof felt tapes, the adjacent two circles of the wound self-adhesive fireproof felt tapes are tightly fitted, the first fire-resistant protective layer 2 and the second fire-resistant protective layer 3 are staggered and wound, and the wrapping force is uniform and tight. The second fire-resistant protective layer 3 is fixed with a fire-resistant cable tie.

[0054] like Figure 5 As shown, the self-adhesive fireproof felt tape comprises a fireproof felt tape and an adhesive layer 8, and the adhesive layer 8 is arranged on the top or bottom of the outer covering layer 7.

[0055] In order to ensure the self-adhesive effect, the adhesive layer 8 is a double-sided adhesive colloid.

[0056] The adhesive layer 8 is a butyl tape with a thickness greater than or equal to 1 mm. The width of the adhesive layer 8 is smaller than the width of the outer covering layer 7, and the distance between the single-side edge of the adhesive layer 8 and the edge of the outer covering layer 7 on the same side is greater than 8 mm.

[0057] This construction method ensures that both fire-resistant protective layers are two complete and continuous winding surfaces, and the adhesion between the two is relatively high. Compared with the two-layer coating and docking binding construction method, it greatly alleviates the problem of the high-altitude fire-resistant protective layer being easy to slide down. By applying a self-adhesive fireproof felt tape, not only the adhesion between the aerogel felt and the main cable surface is directly improved, the flatness of the construction is improved, but also the construction is convenient, and the construction efficiency is greatly improved. The beneficial effects of the fireproof felt tape using aerogel felt are described in Example 1.

[0058] Based on the dimensions involved in the present invention, in engineering construction, under the premise of achieving the same technical effect, errors are allowed in the selection of the dimensions of the materials used or the inevitable deviations in the construction process.

[0059] The above is only a preferred embodiment of the present invention, and is not intended to limit the scope of implementation of the present invention. It should be noted that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should all be included in the protection scope of the present invention.

Claims

1. A method for constructing a main cable protection structure using a fireproof felt tape, characterized in that: The specific steps are as follows: Step 1: Clean the surface of the main cable (1); Step 2: Double-layer fire protection layer construction The main cable surface (1) is provided with a first fire-resistant protective layer (2) and a second fire-resistant protective layer (3) in sequence, and is constructed by a coating, a spiral winding combination method or a spiral winding method; Step 3: Construction of sealing protective layer (4) Firstly, a layer of flame retardant sealant is scraped on the second fireproof protective layer (3), and then a layer of bundle-shaped heat-insulating fiber cloth is wrapped around it; then, a layer of flame retardant sealant is scraped on the second fireproof protective layer (3), and then a layer of bundle-shaped heat-insulating fiber cloth is wrapped around it; Step 4: Application of coating layer (5) A flexible fluorocarbon topcoat is applied on the dried outer surface of the sealing protective layer (4).

2. A method for constructing a main cable protection structure using a fireproof felt tape according to claim 1, characterized in that: The combined method of wrapping and spiral winding in step 2 is that the first fire-resistant protective layer (2) is coated with a flame-retardant fire-resistant felt material on the surface of the main cable (1) by butt-wrapping and fixing with a fire-resistant cable tie, and then a water-based EVA adhesive is applied. The second fire-resistant protective layer (3) thereon is continuously and evenly wrapped with a fire-resistant felt tape, and the two adjacent circles of the fire-resistant felt tape are tightly fitted; the outside of the second fire-resistant protective layer (3) is fixed with a fire-resistant cable tie.

3. A method for constructing a main cable protection structure using a fireproof felt tape according to claim 2, characterized in that: The fireproof felt belt comprises the fireproof layer (6) and an outer covering layer (7); the fireproof layer (6) is accommodated between two layers of the outer covering layer (7), and the edges of each layer are fixed by pressing; the fireproof layer (6) is composed of a single layer or multiple layers of fireproof material; the outer covering layer (7) is a flame-retardant covering cloth.

4. A method for constructing a main cable protection structure using a fireproof felt tape according to claim 3, characterized in that: The fire-resistant layer (6) is composed of a single layer or multiple layers of aerogel felt; the outer covering layer (7) is made of one of double-sided glass fiber cloth, aluminum foil cloth, and high-silica cloth, and the cloth surface gap of the outer covering layer (7) is smaller than the size of the aerogel felt particles.

5. A method for constructing a main cable protection structure using a fireproof felt tape according to any one of claims 3 and 4, characterized in that: The spiral winding method in step 2 is that the first fire-resistant protective layer (2) and the second fire-resistant protective layer (3) are both continuously and evenly wound with self-adhesive fireproof felt tape, and the two adjacent circles of the self-adhesive fireproof felt tape are tightly fitted, and the second fire-resistant protective layer (3) is fixed with a fire-resistant cable tie.

6. A method for constructing a main cable protection structure using a fireproof felt tape according to claim 5, characterized in that: The self-adhesive fireproof felt tape comprises the fireproof felt tape and an adhesive layer (8), wherein the adhesive layer (8) is arranged on the upper side or the lower side of the outer covering layer (7).

7. A method for constructing a main cable protection structure using a fireproof felt tape according to claim 6, characterized in that: The adhesive layer (8) is a double-sided adhesive colloid.

8. A method for constructing a main cable protection structure using a fireproof felt tape according to claim 6, characterized in that: The adhesive layer (8) is a butyl tape with a thickness greater than or equal to 1 mm. The width of the adhesive layer (8) is smaller than the width of the outer covering layer (7), and the distance between a single-side edge of the adhesive layer (8) and an edge of the outer covering layer (7) on the same side is greater than 8 mm.

9. A method for constructing a main cable protection structure using a fireproof felt tape according to any one of claims 2 and 5, characterized in that: The fire-resistant cable ties are 304 stainless steel cable ties with a size of 0.25 mm×10 mm, and are fixed by bundling every 8 to 12 cm.

10. A method for constructing a main cable protection structure using a fireproof felt tape according to claim 1, characterized in that: The total thickness of the flame retardant vulcanized rubber sealant in step 3 is 3000 μm; the thickness of the flexible fluorocarbon topcoat in step 4 is 40 μm.

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