JPH0415792Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The present invention is applicable to anti-corrosion piles driven in places with severe corrosion, such as the coast, and more specifically to untreated areas near the welded upper and lower pile joints. This invention relates to a protective structure for an anticorrosive layer that covers a material.

(Prior art) Conventionally, as shown in Fig. 4, upper and lower piles 1,
2 are covered in advance with a predetermined anti-corrosion layer 3 made of polyethylene resin, leaving an untreated portion near the joint portion 4, but the untreated portion is covered with a heat-shrinkable polyethylene resin layer after welding the joint portion 4. It is covered with a resin anti-corrosion layer 5. At that time, the anticorrosion layer 5 was contracted by heating and polymerized onto the anticorrosion layers 3, 3 of the upper and lower piles 1, 2.

(Problem to be solved by the invention) Since the conventional technology is as described above, when welded upper and lower piles are driven, the lower end of the anticorrosion layer 5 covering the untreated portion directly receives the resistance of the soil. It had the disadvantage that it curled up and was prone to corrosion near the joint.

An object of the present invention is to provide a corrosion-proof pile that can eliminate the above-mentioned drawbacks and sufficiently prevent corrosion in the vicinity of the joint.

(Means for Solving the Problems) The joint structure of the anti-corrosion pile according to the present invention is characterized by having a small diameter portion 6a and a large A first anti-corrosion layer 6 consisting of the diameter portion 6b is applied, a heat-shrinkable second anti-corrosion layer 5 covering the untreated portion of the joint 4 is applied by heating to the small diameter portion 6a, and the second anti-corrosion layer 5 consisting of the large diameter portion 6b is applied to the small diameter portion 6a. The point is that the third corrosion protection layer 3 on the lower pile 2 side is applied.

(Function) Since the joint structure of the anti-corrosion pile according to the present invention is configured as described above, the large-diameter portion 6b of the first anti-corrosion layer 6 applied to the untreated upper part of the lower pile 2 and the lower pile 2 The second anti-corrosion layer 3 forms a friction cutter by polymerizing with the upper end portion of the predetermined third anti-corrosion layer 3, thereby covering the untreated portions above and below the joint.
This prevents the lower end of the anti-corrosion layer 5 from turning up.

(Example) An example of the present invention will be described in detail below with reference to FIGS. 1 to 3.

As shown in Fig. 3, a polyolefin resin tape is wrapped around the upper part of the lower pile 2, and
A first anticorrosive layer 6 is formed, which includes a large diameter portion 6b and a large diameter portion 6b. The thickness of the small diameter portion 6a of the first anti-corrosion layer 6 is approximately equal to the predetermined anti-corrosion thickness of the lower pile 2;
The thickness of a is at least twice the predetermined anticorrosion thickness, and the overall length of the first anticorrosion layer 6 in the vertical direction is about 300 to 400 mm. Then, a predetermined third anticorrosion layer 3 (made of the same material as the first anticorrosion layer 6) of the lower pile 2 is applied to the large diameter portion 6b of the first anticorrosion layer 6 by extrusion coating. As a result, a ring-shaped friction cutter is formed approximately 150 mm below the upper end of the first anticorrosive layer 6.

At the site, the lower pile 2 coated with anti-corrosion layers 3 and 6 as described above is welded to the upper pile 1 at the joint 4, the upper end portion is placed on the predetermined anti-corrosion layer 3 of the upper pile 1, and the lower end portion is coated with the anti-corrosion layer 3. A sheet-like anti-corrosion cover made of heat-shrinkable polyethylene resin is wrapped around the small-diameter portion 6a of the layer 6 so as to be polymerized and heat-shrinked to cover it, thereby forming the second anti-corrosion layer 5. Alternatively, the lower end portion of a tube-shaped anti-corrosion tube made of polyethylene resin may be overlapped with the small diameter portion 6a of the first anti-corrosion layer 6 of the lower pile 2 on which the anti-corrosion layers 3 and 6 have been applied as described above before welding, and after welding the joint portion 4, The second anti-corrosion layer 5 may be formed by pulling the anti-corrosion tube upward and overlapping the lower end portion of the predetermined anti-corrosion layer 3 of the upper pile 1 with the anti-corrosion tube and heat-shrinking the tube.

Of course, any coating is subjected to pretreatment for adhesion.

As shown in FIG. 2, it is desirable to form the lower end of the second anti-corrosion layer 5' into a tapered shape in order to improve the performance of the friction cutter. Also the first
It is desirable that the lower end of the anti-corrosion layer 6 be tapered so as not to interfere with the construction of the predetermined third anti-corrosion layer 3 on the lower pile 2.

(Effect) As can be seen from the above explanation, the present invention
The lower end of the second anti-corrosion layer 5 covering the untreated portion in the vicinity is connected to the large diameter portion of the first anti-corrosion layer 6 and the predetermined third portion of the lower pile 2.
Since the friction vine formed with the anti-corrosion layer 3 does not receive resistance from the soil, it does not curl up, and therefore it is possible to protect the anti-corrosion layer at the joint part and obtain a corrosion-resistant pile that is resistant to corrosion. can.

[Brief explanation of drawings]

Fig. 1 is a longitudinal cross-sectional view showing one embodiment of the joint structure of a corrosion-resistant pile according to the present invention, Fig. 2 is a longitudinal cross-sectional view showing another embodiment of the present invention, and Fig. 3 is a longitudinal cross-sectional view showing an embodiment of the joint structure of a corrosion-proof pile according to the present invention. FIG. 4 is a vertical cross-sectional view of a conventional anti-corrosion pile. 1... Upper pile, 2... Lower pile, 3... Predetermined anti-corrosion layer (third anti-corrosion layer), 4... Joint part, 5... Second anti-corrosion layer, 6... From the small diameter part and the large diameter part corrosion protection layer (first
anti-corrosion layer), 6a... small diameter portion, 6b... small diameter portion.

Claims (1)

[Scope of utility model registration request] At the upper part of the lower pile 2 near the joint part 4 of the upper and lower piles 1 and 2, there is a first part consisting of a small diameter part 6a and a large diameter part 6b.
A corrosion protection layer 6 is applied, and a joint portion 4 is provided on the small diameter portion 6a.
The lower part of the heat-shrinkable second anti-corrosion layer 5 covering the upper and lower untreated parts is applied by heating, and the third anti-corrosion layer 3 on the lower pile side is applied to the large diameter part 6b. Features a corrosion-resistant pile joint structure.