JPH0242972B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a corrosion protection method for uniformizing the thickness of a corrosion protection layer of a steel pipe pile, particularly a steel pipe pile installed in water.

[Conventional technology]

Steel pipe piles installed mainly in the ocean, such as in seawall structures, piers, sea berths, and dolphins, undergo rapid corrosion due to the harsh conditions of the surrounding environment, and to prevent this, on-site anti-corrosion repairs are often performed to cover and paint them. There are many things.

One method for such on-site repairs is to attach a formwork to the outer periphery of the steel pipe pile, fill the gap between the outside surface of the steel pipe pile and the inside surface of the formwork with an underwater curable resin, allow it to harden, and then remove the frame. There is a way to expose the anti-corrosion coating.

In this repair work, it is necessary to maintain a constant gap between the formwork and the steel pipe pile when attaching the formwork to the steel pipe pile in order to make the thickness of the anticorrosive coating uniform, so spacers are used.

[Problem that the invention seeks to solve]

First, there is a method of attaching this spacer to the formwork in advance.In this case, the effect of using the spacer, that is, the gap between the steel pipe pile and the formwork can be secured reliably and uniformly, but the spacer fixed part In order to improve the strength of the formwork, not only is that part complicated, but since the spacer is originally attached to the formwork, when the anticorrosive coating is repaired and the frame is removed, the anticorrosion layer is not present in the area in contact with the spacer. Therefore, a double operation is required, in which case the resin must be added to that part again.

Separately, before installing the formwork, we affix a spacer that itself has corrosion resistance to an appropriate location on the surface of the steel pipe pile, then attach the formwork and pour resin into the gap to create a shape that encloses the spacer. There is a method of removing the frame and leaving the spacer. However, in this case, there was a problem that the spacers might fall off when the formwork was attached, and it was difficult to attach each spacer one by one underwater.

[Means for solving problems]

The present invention was completed by focusing on the above-mentioned points that require improvement, and involves providing a formwork on the outer circumferential surface of a steel pipe pile, injecting an underwater curable resin, and hardening it. In a corrosion protection method for steel pipe piles that forms a corrosion protection layer, a spacer band consisting of a plurality of spacers suspended and supported at approximately equal intervals is fixed to a predetermined position of a steel pipe pile with a single touch on a string-like body with a binding fitting at one end. This invention relates to a formwork corrosion protection method for steel pipe piles, which is characterized by the fact that formwork is later attached.

The spacer used here needs to be sufficiently compatible with or adhesive with the resin to be cast and exhibit sufficient corrosion resistance.

From another point of view, it is preferable that the insulation resistance is high and the water absorption is low.

The material of one string-like body is flexible,
It has an affinity or compatibility with the casting resin, and specifically includes fibers such as polyamide and polyester, rubber, and metal wires.

The spacer and string-like body described above are, for example, the second
As shown in the figure, the steel pipe piles connected at intervals determined according to the desired pitch P determined according to the thickness of the target steel pipe pile and the situation at the location where the pile is erected are used.

The method of connection may be through a string-like body insertion hole that is integrally formed when the spacer is molded, or in some cases, a suitable hole may be bored in the spacer and the string-like body is inserted through the hole. It's okay if it's hot.

One end of the spacer band formed in this way can be tied with one touch by providing a binding fitting as shown in FIG. 1, for example, and locking the spacer band with a wedge portion of the fitting.

It goes without saying that both ends of the string-like body can be simply tied together by hand.

The operation of the present invention will be explained using FIGS. 2 to 8.

FIG. 2 is an example of a spacer band formed according to the present invention, and shows the relationship between two string-like bodies 1 and a spacer 2. In this case, an example is shown in which the spacers 2 are provided at equal intervals in the string-like body 1 at appropriate intervals P.

One end of the string-like body 1 is provided with a binding fitting 3 as shown in FIG. 3, and this metal fitting is designed so that after keeping the string-like body 1 in a tensioned state, the open end thereof is inserted into the insertion opening 4 and folded back. Then, as shown in FIG. 4, it has a locking function.

Therefore, if the spacer 2 is prepared to have a desired thickness, the spacer 2 can be easily set on the target pile without making any other troublesome preparations.

〔Example〕

As shown in FIG. 9, the string-like body 1 with the spacers 2 suspended around the steel pipe pile 5 driven in the water was wrapped around the string-like body 1 and tied together. Thereafter, the formwork 6 was wound and fixed around it, and a uniform gap d could be secured as shown in FIG.

Note that the shape of the spacer may be such that the front shape is as shown in FIGS. 5 to 7, taking into consideration the characteristics such as the viscosity of the casting resin. Moreover, its cross-sectional shape can also take various shapes as shown in FIGS. 8a to 8e.

〔Effect of the invention〕

By implementing the present invention, the following effects can be expected.

(1) Spacer installation work is quick because several or more spacers can be installed on the outside surface of a steel pipe pile with one touch.

(2) Since the spacers are fixed in advance to the string-like body at a certain interval, the spacers are installed on the outer surface of the steel pipe pile at the specified intervals, and the spacers do not twist.

(3) Since it is fixed by the tension of the string-like body, there is no need for adhesives, and it can be fixed to the outer surface of the steel pipe pile even in underwater areas.

(4) Since the string-like body can be connected with one touch using the connecting fittings, it can be easily installed even underwater.

(5) By using the same quality or adhesive material for the spacer as the casting resin, it becomes integrated with the casting resin and forms an anti-corrosion layer, so there is no need to repair the spacer after demolding. .

(6) Spacers can be installed at regular intervals even when the steel pipe pile has changed from a circular shape to an oval shape.

[Brief explanation of the drawing]

Fig. 1 is a front view of the binding fitting, Fig. 2 is a developed front view of the cord-like band with a spacer attached, Figs. Figures 7 to 7 are front views of the spacer, Figures 8a to 8e are cross-sectional views of the spacer, Figure 9 is an explanatory diagram of a steel pipe pile wrapped with a string band, and Figure 10 shows a case where a formwork is applied. It is a partially cutaway front view. 1...String band, 2...Spacer, 3...Binding fittings, 4...Insertion port, 5...Steel pipe, 6...Formwork.

Claims (1)

[Claims] 1 In the corrosion protection method for steel pipe piles, which involves providing a formwork on the outer peripheral surface of the steel pipe pile and injecting an underwater curable resin and curing it to form a corrosion protection layer, a string-like body with a binding fitting attached at one end is placed at a predetermined position on the steel pipe pile. A formwork corrosion prevention method for steel pipe piles, characterized in that a spacer band in which a plurality of spacers are suspended and supported at approximately equal intervals is fixed with one touch, and then a formwork is attached.