JPS6299485A - Corrosion preventive material and method for shape steel - Google Patents

Abstract

PURPOSE:To prevent the corrosion of a shape steel to be used in corrosive environment by pressing and fixing a corrosion preventive material formed by adhering water impermeable films and corrosion preventive sheets to both faces of respectively uncured FRPs by using jigs. CONSTITUTION:The flexible and water impermeable film 1C is adhered to one face of the FRP consisting of the cured FRP 1a near through-holes 1e for penetration of screw bodies and the uncured FRP in the other part and the corrosion preventive sheet 1d having self-adhesiveness, water impermeability, electrical insulating characteristic, etc., is adhered to the other face to form the corrosion preventive material 1. The above-mentioned corrosion preventive material 1 is deposited on the surface of a steel sheet pile 2 prior to the curing of the liquid curing resin of the uncured FRP 1b. The screw bodies 3 embedded in the sheet pile 2 are penetrated into the above-mentioned through-holes 1e. A hard backing strip 7 is pressed to the recesses 2a, 2b of the steel sheet pile via the screw bodies 3 and is tightened and fixed by tightening members 5 and tightening jigs 8. The surface of the steel sheet pile 2 is thereby coated with the above-mentioned material 1 and is thus subjected to the corrosion preventive treatment.

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial Application Field" The present invention relates to a method for protecting steel sections used in corrosive environments.

More specifically, the present invention relates to methods for preventing corrosion of shaped steel, such as steel sheet piles or steel pipe sheet piles, which are mainly driven into the sea and used as the foundations of seawalls and quays, in the underwater area, tidal zone, and stagnation zone.

[Conventional technology 1] In general, steel materials used in the marine environment are not only immersed in seawater containing a large amount of salt, washed by waves and currents, but also exposed to spray or the ocean atmosphere containing sea salt particles. This causes corrosion and wear and tear, and if it is not perforated during long-term use, it can lead to destruction.

In the past, various methods have been proposed to prevent this kind of corrosion. One of them is to coat heavily corroded areas with a corrosion-resistant material such as petrolaum dam, and then coat the outside with anti-corrosive materials such as petroleum dam. To prevent the peeling and damage of the anti-corrosion layer when subjected to external impact or pressure such as a collision with an object, and to clarify the penetration of seawater into the anti-corrosion layer and the elution of the anti-corrosive material into the sea. Methods of applying protective covers are known. (For example, Japanese Unexamined Patent Publication No. 5'1-II'1471F1, Publication No. 55-
1'1515, etc.) [Problems to be Solved by the Invention] However, although the above-mentioned protective cover was effective in protecting the anti-corrosion layer from external impact and pressure, It has been impossible to stop the infiltration of seawater and the elution of protective materials into seawater.

That is, the above-mentioned protective cover is usually made by laminating fibers such as glass or polyester and liquid hardened resin on the inner or outer surface of a molding die manufactured to match the shape of the steel section to be protected against corrosion. However, slight differences in shape between the above-mentioned forming mold and the section steel are unavoidable, and there are manufacturing differences in the ε steel itself;
Not only is it extremely difficult to manufacture a protective cover suitable for the lla shape of a section steel due to shrinkage during curing of the liquid hardening resin impregnated into the fibers, but it is also difficult to create a protective cover suitable for the lla shape of the section steel. Since unevenness is unavoidable, a gap may be created between the anti-corrosion layer and the protective cover, and seawater may enter the anti-corrosion layer, deteriorating the anti-corrosion performance (4).
There was a problem in that long-term corrosion protection could not be achieved due to seawater penetrating into the surface of the shaped steel inside the corrosion protection layer.

[Prior Art 2] In order to solve the above-mentioned problems with the protective cover, the applicant used a protective cover in which a cushioning material such as plastic foam or the like is pasted on the inside of a fiber-reinforced plastic ivy board. proposed a corrosion-resistant coating (Utility Model Publication No. 56-9703),
Practical for coating and preventing corrosion on steel materials of various shapes.

[Problem 2 to be solved by the invention] However, the protective cover to which the above-mentioned cushioning material is attached completely adheres to the anti-corrosion layer coated on a single section steel or steel pipe, and seawater does not penetrate into the anti-corrosive layer. Is it possible to prevent the elution of anti-corrosion and corrosion-resistant materials into seawater? However, it is difficult to completely adhere to the protective cover, and a gap may form between the anticorrosion layer and the protective cover, allowing seawater to enter the anticorrosion layer as described above, or causing the anticorrosive material to leak into the seawater. However, there still remained problems such as long-term corrosion protection being impossible.

This is due to the fact that steel sheet pile quays and steel pipe sheet pile quays are not constructed from a single section steel, but are constructed by connecting multiple section steel sections and driving them into the soil.

In other words, it is difficult to drive each section of steel into the soil in a straight line due to differences in sea conditions such as waves and currents, and physical conditions such as the hardness and softness of the ground. This is because the orientation of each steel section differs slightly at the connecting part, so the cross section of the entire wall where the section steels are connected has an irregular shape everywhere. .

This invention improves the above-mentioned problems that occur when applying corrosion protection, and provides corrosion protection by adhering not only to a single section steel but also to irregularly shaped walls made by connecting multiple sections without any gaps. This was done for the purpose of forming a coating layer with excellent strength and durability.

[Means for Solving the Problem] In order to achieve this object, the present invention has the following configuration.

That is, the anticorrosion material for shaped steel according to the first invention is hardened at least in the vicinity of the screw body where the through hole is provided, and is applied to one surface of the FRP where the liquid hardened resin in other parts is unhardened. A resin film having flexibility is adhered thereto, and an anticorrosion sheet having anticorrosion properties such as adhesiveness, water impermeability, and electrical insulation properties is adhered to the other side.

Further, in the method for preventing corrosion of a shaped steel according to the second invention, the surface of the shaped steel in which the threaded body is implanted is hardened at least in the vicinity where the through hole for penetrating the threaded body is provided, and the liquid in the central part is hardened. The flexible resin FILNO is adhered to one side of the FRP, where the cured resin is not yet cured, and the anticorrosion sheet i. After the anticorrosive material for the bonded shaped steel is applied before the liquid hardened resin is cured, the anticorrosion sheet faces the surface of the shaped steel, and the screw body passes through the through hole. , a hard backing plate formed to overlap the shape of the recess of the section steel is pressed against the recess of the section steel, and a screw body implanted in the section steel and a tightening member screwed thereto and/or The feature is that the tightening is fixed using a tightening jig.

[Function] The anti-corrosion material according to the present invention has a corrosion-resistant sheet that is highly adhesive, water-impermeable, and electrically insulating, and a portion that is in charge of the deformation of the section steel during anti-corrosion construction is soft, and hardens after the anti-corrosion construction. Since the FRP as a protective material of the anti-corrosion sheet and the water-impermeable resin sheet are bonded together, the anti-corrosive material and the protective material can be applied to the shaped steel at the same time. The anti-corrosion material applied to the section steel is crimped using a hard patch formed to polymerize, and the FRP is molded to match the shape of the section steel before construction, so the anti-corrosion material prevents deformation of the section steel. It can freely adhere to the surface of the shaped steel, completely coating it and preventing corrosion.

Furthermore, the soft part of FRP contained in the anti-corrosion material hardens and increases its strength after construction, so the anti-corrosion sheet inside the FRP can be strongly protected.

[Embodiments] The present invention will be explained below based on embodiments shown in the drawings.

The embodiments shown in FIGS. 1 and 2 are explanatory diagrams regarding the anticorrosion material of the first invention.

FIG. 1 is a sectional view, and FIG. 2 is a schematic explanatory view.

FIG. 3, FIG. 4, and FIG. 5 are examples of a steel sheet pile quay according to the second invention.

FIG. 3 is a perspective view, FIG. 4 is a sectional view of a main part, and FIG. 5 is a completed sectional view.

In Figures 1 and 2, the through hole (1
The area where e) is provided is an FRP (la) made by impregnating a cloth or mat with a liquid cured resin and hardening it, and adjacent to this cured FRP is an FRP (la) made by hardening a liquid cured resin. There is uncured F, RP (Ib) impregnated into a continuous cloth or mat.

A water-impermeable film (lc) is adhered to one side of the FRP, and an anti-corrosion sheet (1d) having anti-corrosion properties such as adhesiveness, water-impermeability, and insulation properties is adhered to the other side. has been done.

In the above, the hard part of FRP is provided in the flat part of the steel section, and the uncured soft part of the cured resin is provided in the position corresponding to the bending part of the section steel and the connection part between the steel sheet piles.

As the water-impermeable film used in this invention, a synthetic resin film such as polyethylene or vinyl chloride resin, a flexible epoxy resin, or a film obtained by impregnating a cloth or mat with a modified polyester resin is used.

Preferably, a film is used in which a mat made of polyester i-fiber is impregnated with a flexible polyester resin.

The anti-corrosion sheet used is a sheet formed by mixing modified rubber and petrolatum-based anti-corrosion.

Next, in FIGS. 3 and 4, the above-mentioned anti-corrosion material (1) is applied to the steel sheet pile <2) on which the screw body (3) is installed, and the liquid hardened material impregnated in a part of this anti-corrosion material is Before the resin hardens, the anti-corrosion sheet (Id) adhered to the anti-corrosive material is placed so that it faces the surface of the steel sheet pile, and the screw body (3) passes through a hole provided in the anti-corrosive material. After the steel sheet pile is installed, a hard backing plate (6) formed to overlap the shape of the recess (2a) of the steel sheet pile and provided with a through hole for the screw body is placed near the recess (2a) of the steel sheet pile. The screw body passes through the through hole of the above-mentioned backing plate and is pressed and fixed into the recess (2a) of the steel sheet pile using the backing seat plate (4) and the tightening member (5).

Furthermore, a hard patch plate (7) formed to overlap with the shape of the recess (2h) of the steel sheet pile is attached to the recess (2h) of the steel sheet pile.
The plate is pressed against the steel sheet pile using the tightening screw (8a) of the tightening jig (8), which is fixed by a screw body planted in the center of the front surface of the steel sheet pile and a tightening member screwed onto this screw body. Tighten firmly.

The uncured liquid cured resin impregnated into the cloth or mat of the anticorrosion material (1) is surrounded watertight by an impermeable film, an impermeable anticorrosion sheet, and cured FRP. It will not leak outside.

When a steel sheet pile is coated with anti-corrosion coating as described above, the unhardened FRP (Ih) hardens within a few hours and the whole becomes a hard FRP.
A polymerized coating is formed into RP in the shape of a steel sheet pile.

Next, FIG. 5 shows the state in which the caul plates (6) and (7) and the tightening jig (8) have been removed after the anti-corrosion coating has been carried out as described above.

(9) is a synthetic resin cap, and other parts are given the same reference numerals as in FIG. 4. The synthetic resin cap (9) is for protecting the screw body from corrosion.

The caul plate and tightening jig used in this invention are normally removed, but they may be left attached (Q).

In this invention, the method of implanting the threaded body in the shaped steel includes a method using electric welding and a method of drilling a hole in the steel sheet pile, cutting a tapped screw, and screwing the threaded body.

As the threaded body installed by electric welding, a bolt made of mild steel or a stainless steel bolt may be used.

Mild steel bolts, stainless steel bolts, brass bolts, and titanium bolts are used as the screw bodies that are screwed onto the tap screws and implanted.

Preferably, mild steel bolts or stainless steel bolts are used and are implanted into the steel sheet pile (2) by electric welding.

The anti-corrosion material used in this invention can be applied directly to the surface of the shaped steel, but if the surface of the shaped steel is corroded or has irregularities such as joints, it may be necessary to use a soft, adhesive, water-impermeable, electrically insulating material, etc. After applying the anticorrosion paste, apply the anticorrosion material.

[Effects of the Invention] As described in detail above, according to the present invention, an anticorrosion sheet having adhesive properties, water impermeability, and electrical insulation properties is applied to the surface of the section steel, and deformed and bent portions of the section steel are coated during anticorrosion construction. The part corresponding to the corrosion protection is soft, and the FRP and water-impermeable resin sheet that hardens after the anti-corrosion coating is adhered to the anti-corrosion sheet, so it can be coated closely to the shaped steel. In addition, it is possible to cover irregularly shaped portions such as those where a plurality of connected steel sections are oriented in a W direction with sufficient tightness.

Furthermore, the water-impermeable outer layer of the anti-corrosion material is flexible and has a buffering function, so it absorbs external impact and protects the inner FRP and anti-corrosion sheet.

Moreover, since the soft part of FRP hardens after a certain period of time and increases its strength, it has sufficient strength as a protective material for the anti-corrosion sheet, and the anti-corrosion sheet can be strongly protected.

Furthermore, the anti-corrosion material is secured by a threaded body embedded in the shaped steel and a tightening member screwed onto this threaded body, allowing for long-term corrosion protection without failure. becomes.

Further, since the above-mentioned anti-corrosion material can be applied underwater, and the above-mentioned anti-corrosion +4 material is watertightly surrounded by an impermeable film, the present invention can be applied to shaped steel in water very easily. It is something that can be implemented.

As mentioned above, the present invention contributes to the corrosion protection of shaped steel! j, it is extremely large.

[Brief explanation of drawings]

FIG. 1 and FIG. 2 are explanatory diagrams regarding the anticorrosion material for the section steel of the first invention. 3, 4, and 5 are explanatory diagrams of an embodiment of the steel sheet pile quay of the second invention, and FIG. 3 is a perspective view,
FIG. 4 is a sectional view of the main part, and FIG. 5 is a completed sectional view. (1)・・・・・・・・・ Anti-corrosion material: (Ia
) Hard Ihi FRP (Ih) Uncured FRP (1c) Impermeable film (1d) Anticorrosion sheet (!e) Through hole

Claims (2)

[Claims] (1) F in which at least the vicinity of the through-hole of the screw body is hardened, and the liquid hardened resin in other parts is unhardened.
A shaped steel made by adhering a flexible, water-impermeable film to one side of RP and adhering an anti-corrosion sheet with adhesive, water-impermeable, electrically insulating and other anti-corrosion properties to the other side. Anti-corrosion material. (2) One side of the FRP where at least the vicinity of the through-hole for the screw body is hardened on the surface of the shaped steel with the screw body implanted, and the liquid hardened resin in other parts is unhardened. A flexible, water-impermeable film is adhered to one side, and the other side is
An anticorrosion material for a shaped steel, which is made by adhering an anticorrosion sheet having anticorrosion properties such as adhesiveness, water impermeability, and electrical insulation, is applied to the steel section by applying an anticorrosion material to the section steel, with the anticorrosion sheet facing the surface of the section steel, before the liquid hardening resin hardens. , and after the screw body is attached so as to pass through the through hole, a hard patch plate formed so as to overlap the shape of the recess of the section steel is pressed against the recess of the section steel, and the section steel is removed. 1. A method for preventing corrosion of a shaped steel, which comprises tightening and fixing the shaped steel using a screw body installed in the body and a tightening member and/or a tightening jig screwed onto the screw body.