JPS6123097Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an anti-corrosion coating coated to prevent corrosion of the outer surface of an outdoor steel structure or the like.

Steel pipe piles used in outdoor steel structures, such as the piers of the Nagashi Bridge, are subject to severe corrosion, especially in areas where the tide is ebb and flow and where seawater is splashed, but no satisfactory method of protecting piers has been found to date. Not yet. In addition, the piers for the Sagashi Bridge must be constructed in seawater, so
There is a problem in that it is difficult to install the protective material.

Conventional methods for preventing corrosion of outdoor steel structures include painting, synthetic resin lining, tape coating, or wrapping with anticorrosion tape and then covering the outside with a protective sheet made of synthetic rubber or synthetic resin. Since these all use organic materials, they burn at high temperatures, so they could not be used in places that require fire resistance. Concrete coatings are also used as fire-resistant and anti-corrosion coatings, but concrete coatings are difficult to construct, and if the thickness of the coating is too small, cracks may occur during hardening and drying, and environments where salt can penetrate and carbon dioxide can diffuse. Corrosion protection performance deteriorates relatively quickly in some areas, so it is necessary to cover the concrete thickly, but a thick concrete coating may place a large load on the structure, which may pose a safety problem in terms of the strength of the structure. However, it had a drawback that it could not be applied to many structures.

In view of the above-mentioned drawbacks, this invention was made with the aim of providing a corrosion-resistant coating that is fire-resistant, lightweight, easy to install, and can exhibit corrosion-preventing effects over a long period of time. .

In other words, the gist of the present invention is that the surface of the structure to be protected against corrosion is coated with a bituminous adhesive material that has waterproof properties and adhesive properties, and the outside of the adhesive material is covered with an exterior material that is lightweight, has heat insulating properties, and has fire resistance. It has a fire-resistant and anti-corrosion coating.

Next, one embodiment of this invention will be described by way of an example.

FIG. 1 is a sectional view of the main part of the anticorrosion material used in this invention. A 5 cm thick lightweight fireproof exterior material 1 made of compression-molded calcium silicate crystals reinforced with glass wool is coated with an adhesive asphalt paint (mainly consisting of rubber asphalt and a solvent) anti-corrosion layer 2 on one side. It is adhered to a thickness of 3 mm and is integrated with the fireproof exterior material to form a coating anticorrosion material. Figure 2 shows the state in which this anti-corrosion material is wrapped around the foundation steel pipe pile 4 of the bridge.
The anti-corrosion material having the asphalt paint 2 adhered to the inner surface thereof is tightly fastened to the steel pipe pile by a corrosion-resistant stainless steel band 3 and is tightly covered. For testing, a test piece of a steel pipe coated in the same manner as shown in Figure 2 was immersed in seawater, and after 6 months had elapsed, it was taken out and inspected, and almost no abnormalities were observed in the steel pipe. As a comparative test, a steel pipe coated with only the above-mentioned asphal paint showed corrosion in some parts, and a steel pipe coated only with the above-mentioned calcium silicate exterior material showed corrosion on the entire surface.

The above example shows a lightweight fire-resistant exterior material made by compression molding calcium silicate crystals mixed with reinforcing materials, but other materials such as calcium silicate, foamed gypsum, and glass fiber that do not contain reinforcing materials are also used. Foamed gypsum materials containing reinforcing materials, porous cement, molded products of carbonized cork, etc. may also be used. Calcium silicate-based fireproof exterior materials are preferred because they are easily available. It is appropriate for the fireproof exterior material to be lightweight, with a bulk specific gravity of approximately 1.5g/ ^cm3 or less, especially approximately
It is preferably 1.0 g/cm ³ or less. Furthermore, fireproof exterior materials generally have not only fire resistance but also heat insulation properties, and protect the adhesive material on the inner surface.

In addition to the rubber asphalt-based adhesive mentioned above, various bituminous materials can be used as the adhesive material to be attached to the inner surface of the fireproof exterior material. Examples of bituminous materials are asphalt, coal tar, or their combinations of oil-drying,
Some are blended with one or more of other oils and fats, rubber, synthetic resins, fillers, gilsonite, petroleum pitch, coal tar pitch, etc. Rubber asphalt-based materials are preferable because they have excellent water-blocking properties, anti-corrosion properties, as well as elasticity and weather resistance. These bituminous materials can be diluted with industrial gasoline, toluene, xylene, or other organic solvents, or heated and melted to adhere to fireproof exterior materials. These bituminous materials are conventional and are described in detail in, for example, "Asphalt and Its Applications" published by the Asphalt Industry Association. The adhesive material used in the present invention may also contain a curing agent, such as a mixture of an epoxy resin and an epoxy resin curing agent.

Alternatively, the adhesive material can be impregnated into juute cloth, felt cloth, etc., and the juute cloth, felt cloth, etc. sufficiently containing the adhesive material can be attached to the fireproof exterior material. The bituminous adhesive material can also be applied directly to the steel structure and coated with a sheathing material thereon.

The thickness of the fireproof exterior material is increased or decreased as appropriate depending on the required fireproof performance. Furthermore, the fire-resistant exterior material can be molded into various shapes according to the shape of the steel material to be protected against corrosion, or it can be used in the form of a pine or sheet wrapped around it. When coating the structure to be protected with this anticorrosion material, the structure may or may not be primed. When coating structures in the sea or underwater, water is removed by coating and tightening the anticorrosive material onto the structure. The outer surface of the covering body usually only needs to be fastened with a band, but if necessary, it may be covered with a stainless steel plate, an aluminum plate, an iron plate, etc.

Since this invention is constructed as described above, even if there are local irregularities on the surface of the steel material to be protected, the adhesive layer adheres to the surface of the steel material to be protected and prevents the intrusion of water and air, which are the causes of corrosion. Furthermore, the outer fireproof exterior material has not only fire resistance but also heat insulation properties and an appropriate thickness, so the inner adhesive material is protected from climate change, fire, and physical impact, so it has excellent corrosion and fire resistance. It is extremely effective for protecting outdoor steel structures, etc. The present invention can be easily installed on structures by pasting anti-corrosion material on the inner surface of the exterior material in advance, and is especially suitable for structures where undercoating cannot be applied or water cannot be removed, such as underwater or underwater structures. Particularly suitable for covering bridge piers, etc. In recent years, the number of liquefied gas cargoes has increased, and countermeasures against fires at bridges are required, and the coated anti-corrosion body of the present invention is suitable for this purpose as well. Furthermore, the anticorrosive material used in the present invention is lightweight, reducing the burden on the structure and enabling long-term protection of the structure. Furthermore, the bituminous adhesive material used in the present invention not only has excellent water-blocking properties and anti-corrosion properties, but is also advantageous in that it is easily available. The fire-resistant and anti-corrosion material used in this invention is
Of course, it can also be used for corrosion protection of steel structures that do not require fire resistance.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part of the anticorrosive material used in this invention, and FIG. 2 is a perspective view of an embodiment of the invention. 1... Fireproof exterior material, 2... Adhesive material, 3... Fireproof stainless steel band, 4... Steel pipe pile.

Claims (1)

[Scope of utility model registration request] A bituminous adhesive material that has waterproof and adhesive properties on the surface of the structure to be protected from corrosion, and calcium silicate, foamed gypsum, porous cement, or carbonized cork that is lightweight, heat-insulating, and fire-resistant on the outside of the adhesive material. A fire-resistant and anti-corrosion covering covered with an exterior material consisting of.