JP2960637B2 - Corrosion protection structure of steel pipe pile - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anticorrosion structure for a steel pipe pile, and more particularly, to a corrosion prevention structure for a steel pipe pile in a marine structure, which covers a splash or a tidal zone of seawater on the steel pipe pile.

[0002]

2. Description of the Related Art Steel pipe piles of offshore structures are subjected to anticorrosion treatment such as painting in order to prevent seawater corrosion. Corrosion proceeds unbearably.

[0003] Anticorrosion is performed by applying a resin coating of an epoxy resin or a fluororesin.
In the tidal zone, long-term anticorrosion is impossible, and repairing is also impossible, so the service life of the structure is determined by the corrosion resistance of the resin.

On the other hand, an anticorrosion construction method using a titanium plate having extremely excellent corrosion resistance is disclosed, for example, in Japanese Utility Model Application Laid-Open No. Sho 62-44948. That is, an L-shaped steel 7 made of titanium is attached to a steel pipe pile 1 coated with a resin 3 as shown in FIG. 5A by welding 9, and both ends of the titanium plate 2 are connected to the L-shaped steel as shown in FIG. 5B. 7 proposes a method of tightening with titanium screws 8 to cover the surface of the steel pipe pile 1 and prevent corrosion. However, the production cost is high due to the welding work of the titanium thin plate end and the titanium L-shaped steel, and the installation of the cover of the existing steel pipe pile is underwater due to the screw structure, so it is necessary to attach by a diver There are also drawbacks such as extremely high mounting cost.

[0005]

SUMMARY OF THE INVENTION The present invention is to improve a conventional corrosion prevention structure of a steel pipe pile made of a titanium plate, and when the steel pipe pile is wound around a seawater splash / tidal zone,
It is an object of the present invention to provide a simple and reliable steel pipe pile anticorrosion structure.

[0006]

In order to achieve the above object, the present invention has the following constitution. That is, (1) in a corrosion prevention structure of a steel pipe pile, a titanium or titanium alloy plate is wound around a steel pipe pile whose surface is coated with a seawater-resistant insulating material by bending both ends in the axial direction of the steel pipe pile outward, and An anticorrosion structure for a steel pipe pile, wherein a bent portion is fitted and inserted into a fitting member in which a seawater-resistant insulating material is coated on the inner surface of a titanium or titanium alloy plate having a bent portion processed into a C shape. And (2) In the corrosion prevention structure of a steel pipe pile, a titanium or titanium alloy plate coated on one side with a seawater-resistant insulating material is coated on the steel pipe pile, and both ends in the axial direction of the steel pipe pile are outside with the coated surface inside. Wherein the bent portion is fitted and inserted into a fitting member having a C-shaped titanium or titanium alloy plate coated with a seawater-resistant insulating material on the inner surface thereof. It is a structure.

[0007]

The anticorrosion structure of a steel pipe pile according to the present invention has a surface coated with a seawater-resistant insulating material such as a resin.
Even when the titanium or titanium alloy plate is wound, the two do not come into direct contact with each other, and galvanic corrosion (electrolytic corrosion) caused by a potential difference between steel and titanium does not occur.

[0008] Further, a titanium or titanium alloy plate is bent outward at both axial ends of the steel pipe pile and wound around the steel pipe pile,
Since the bent portion is fitted to a fitting member of a titanium or titanium alloy plate whose cross section is processed into a substantially C shape (hereinafter simply referred to as a C shape), the installation work of the steel pipe pile of the existing offshore structure is also possible. It can be easily implemented from the sea. In addition, since the resin is applied to the inner surface of the fitting member, a structure in which seawater does not enter can be obtained.

The seawater-resistant insulating material coated on the surface of the steel pipe pile and coated on the inner surface of the fitting member processed into a C shape is made of epoxy resin, polymer resin, fluororesin, mortar, adhesive rubber material or the like. be able to.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on an embodiment shown in the drawings. FIG. 1 shows an example of a corrosion prevention structure for a steel pipe pile according to the present invention. The surface of an existing JIS 5525 steel pipe pile 1 having an outer diameter of 400 mm is coated with a polymer resin 3 and the steel pipe pile 1 is covered with a titanium plate 2. That is, as shown in FIG. 2, the steel pipe pile 1 coated with the polymer resin 3 is provided with bent portions 4 and 4 'at both ends in the axial direction of the steel pipe pile having a thickness of 1.0 mm. Next, the fitting member 5 processed into the C shape shown in FIG.
The bent portions 4, 4 'of the titanium plate 2 wound around the steel pipe pile 1 are inserted from above and fitted. In addition,
The tip of the fitting member 5 is tapered 6 to facilitate insertion. FIG. 4 is an enlarged view of a portion where the bent portions 4 and 4 ′ of the titanium plate are inserted and fitted into the fitting member 5.

In FIG. 4, a C-shaped titanium plate 2 is wound around the surface of a flexible resin 3 coated on a steel pipe pile 1, and a fitting member 5 having an inner surface coated with a resin 3 'is attached to a fitting member 5.
Since the bent portions are inserted and fitted, a completely close contact structure is provided, so that the entry of seawater can be completely blocked.

When the surface of the resin 3 coated on the steel pipe pile 1 is hardened and lacks flexibility, a flexible resin is applied to the inner surface of the titanium plate 2 processed into a C shape and wound. The bent portion 4 is attached to a fitting member 5 having an inner surface coated with resin.
Are fitted to each other to form a completely close contact structure, so that the ingress of seawater can be completely shut off. The same effect can be achieved even if the resin 3 is coated on either the steel pipe pile 1 or the titanium plate 2.

With such a structure, a seawater-resistant insulating material such as a polymer resin coated on a steel pipe pile or a titanium plate (titanium alloy plate) protects and completely seals the surface of the steel pipe pile. Therefore, corrosion of the steel pipe pile due to seawater intrusion can be prevented. In addition, the current generated by the potential difference between steel and titanium in the pile body is insulated, and galvanic corrosion of the steel pipe pile can be prevented. Needless to say, the same effect can be obtained by winding the steel pipe pile 1 with a titanium alloy.

[0014]

As described above, according to the present invention, a steel pipe pile, which is an existing offshore structure, can be easily and reliably protected from splashing and tidal zones by seawater. Effect is extremely large.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a corrosion prevention structure of a steel pipe pile according to the present invention.

FIG. 2 is a perspective view showing an example of a titanium plate wound around a steel pipe pile used in the present invention.

FIG. 3 is a perspective view showing an example of a fitting member used in the present invention.

FIG. 4 is a sectional view taken along line AA ′ of FIG. 1;

5 (a) and 5 (b) are perspective views showing examples of a conventional anticorrosion structure.

[Description of Signs] 1 Steel pipe pile 2 Titanium plate 3, 3 'Seawater resistant insulating material (resin coating) 4, 4' Titanium plate bent part 5 Fitting member 6 Taper 7 Titanium L-shaped steel 8 Titanium screw

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kazuo Sakai 2-6-3 Otemachi, Chiyoda-ku, Tokyo Inside Nippon Steel Corporation (72) Inventor Yasuo Takahashi 2-6, Otemachi 2-6, Chiyoda-ku, Tokyo 3. Inside Nippon Steel Corporation (56) References JP-A-61-10348 (JP, U) JP-A-62-44948 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB Name) E02D 31/06 E02D 5/28 E02D 5/60

Claims (2)

(57) [Claims] An anticorrosion structure for a steel pipe pile, wherein a titanium or titanium alloy plate is wound around a steel pipe pile whose surface is coated with a seawater-resistant insulating material by bending both ends in the axial direction of the steel pipe pile outward, and A corrosion prevention structure for a steel pipe pile, wherein the bent portion is fitted and inserted into a fitting member in which a seawater-resistant insulating material is coated on the inner surface of a titanium or titanium alloy plate processed into a C shape. 2. An anticorrosion structure for a steel pipe pile, wherein a titanium or titanium alloy plate coated on one side with a seawater-resistant insulating material is coated on the steel pipe pile, and both ends in the axial direction of the steel pipe pile are coated with the coated surface inside. A steel pipe pile characterized in that it is bent outward and wound, and this bent portion is fitted and inserted into a fitting member in which a seawater-resistant insulating material is coated on the inner surface of a titanium or titanium alloy plate processed into a C shape. Anticorrosion structure.