JP2511296B2 - Structure of anticorrosion cover - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a circumference of an underwater structure that comes into contact with water in order to prevent corrosion of an underwater structure such as a steel pipe pile or a reinforced concrete pile that is driven into water. The present invention relates to an anticorrosion cover attached to a surface.

2. Description of the Related Art Steel pipe piles or reinforced concrete piles placed on the seabed in a harbor or the like are likely to be corroded by seawater at the surface in contact with seawater.

Therefore, various measures have been conventionally taken to prevent the corrosion of such an underwater structure.

The generally used cover method is to wrap a pile surface with a petrolatum tape as an anticorrosion layer, with a cushioning material made of various foams as an intermediate layer, and surrounding it with a fiber reinforced resin (FRP). It has a structure covered by a protective cover.

The protective cover is a cylindrical body divided in half,
Foam is lined on its inner peripheral surface, applied from both sides to the peripheral surface of the anticorrosion layer wrapped around the pile, and the flanges protruding from the sides of each protective cover are tightened with bolts to form the anticorrosion layer. Close to the sea to block seawater from the surface of the pile.

Some of the above structures do not have an intermediate cushioning material, and in that case, it is necessary to sufficiently secure the tightening margin such as the packing shape and thickness of the flange tightening portion of the protective cover.

Problems to be Solved In the conventional structure of the anticorrosion cover, the anticorrosive material is pressed against the pile by the tightening pressure at the time of construction, and the pressure after construction is not strengthened with time.

Therefore, at the time of construction, selection of materials, structure and construction method in consideration of adhesion to piles and sufficient anticorrosion property are required, resulting in high cost and complicated construction.

In addition, various foaming materials as intermediate cushioning materials have relatively low mechanical properties and soft characteristics, so there are cases where an excessive load such as a heavy cover weight cannot be applied, and design restrictions and countermeasures are required. Become.

Means and Actions for Solving the Problems The present invention has been made in view of the above points, and the purpose thereof is to provide a water swelling mechanism to simplify the construction and to provide an optimal design of an anticorrosion cover. The point is to provide the structure.

That is, the present invention, in the structure of the anticorrosion cover attached to the anticorrosion area of the underwater structure such as piles driven in water,
From an inner layer made of food-proof material and in direct contact with the structure, an outer layer made of a protective cover, and an intermediate layer made of a water-swelling material occupying a predetermined range and a foaming material occupying the remaining range between the inner layer and the outer layer. This is the structure of the anticorrosion cover that is configured.

Since the water swelling material is interposed in the intermediate layer, it is possible to increase the degree of adhesion of the food protection material to the pile after construction, improve corrosion resistance and durability, and perform complicated operations such as setting the clamping pressure during construction. To make construction easy.

In addition, an optimal anticorrosion design is possible by appropriately disposing a water swelling material and a foam material as the intermediate layer.

Furthermore, the water swelling material can protect the foam material,
The durability against external damage is also improved.

Embodiment An embodiment according to the present invention shown in FIGS. 1 to 10 will be described below.

FIG. 1 is a perspective view showing a state in which the anticorrosion cover 2 according to the present embodiment is attached to a steel pipe pile 1 that is struck on the seabed.

A pair of protective covers 3 obtained by dividing the cylindrical body in half are applied to the surface anticorrosive area of the cylindrical steel pipe pile 1 from both sides through the anticorrosion material and the intermediate material, and project on the side portions of each protective cover 3. The flanges 4 are tightened with bolts 9 to fix the anticorrosion cover 2 to the steel pipe pile 1 at a predetermined position.

The protective cover 3 used here is a molded product of fiber reinforced resin FRP made of glass fiber and polyester resin,
The details are shown in FIGS. 2 to 5 and 6.

The semi-cylindrical protection cover 3 has bolt holes 5 provided at equal intervals along the longitudinal direction on a flange 4 projecting from its side, and the back surface of the flange 4 and the outer peripheral surface of the main body of the protection cover 3 are provided. A plurality of substantially triangular reinforcing portions 6 are provided in the upper part and the lower part so as to reinforce the flange 4 to which the tightening force of the bolt 9 directly acts.

The main body of the protective cover 3 is provided with water-conducting holes 7 penetrating the protective cover 3 in the upper portion and the lower portion as appropriate.
On the inner peripheral surface where the water guiding holes 7 are provided, water guiding grooves 8 are formed in a vertical and horizontal lattice shape so as to communicate with the water guiding holes 7 (see FIGS. 4 and 5).

A water swelling material 10 and a foam material 11 are lined on the inner peripheral surface of the protective cover 3 as shown in FIG.

The upper and lower parts are water swelling materials 10, and the foam material 11 occupies the central portion sandwiched between them.

The water guiding hole 7 and the water guiding groove 8 are formed on the inner peripheral surface of the main body of the protective cover 3 on which the upper water swelling material 10 is lined.

 The same applies to the lower water swelling material 10.

Therefore, in the upper part and the lower part of the anticorrosion cover 2, water penetrates through the water guiding holes 7 to reach the water swelling material 10, and is further guided to the water guiding groove 8 to reach the outer peripheral surface of the water swelling material 10.

The water swelling material 10 can absorb this water and expand.

The water swelling material 10 is made of a vulcanized rubber or other plastic as a base material and a water-absorbing polymer mixed therein, and preferably has a volume expansion coefficient of 5 to 1000%.

FIG. 7 shows a state in which a pair of protective covers 3 lined with the water swelling material 10 and the foam material 11 are combined in this way.

The gasket 13 is sandwiched between the flanges 4 of the protective cover 3 which are opposed to each other, the bolt 9 penetrates the bolt hole 5 and the gasket 13 and is tightened, and the protective covers 3 tighten the steel pipe pile 1 therein.

An elongated set plate 14 is stretched in the vertical direction on the inner peripheral surface of the seam of both flanges 4 along the seam.

The gasket 13 is sandwiched between the flange 4 and the ends of the water swelling material 10 or the foam material 11 and reaches the set plate 14. Even if there is water that the set plate 14 should try to penetrate from the gasket 13, While the set plate 14 is made of FRP, the water swelling material 10 or the foam material 11 smoothly moves on the outer surface of the set plate 14 when tightened by a bolt, and the tightening is performed smoothly. Be useful.

As shown by notching in FIG. 7, the water swelling material 10 is lined on the upper and lower portions of the protective cover 3, and the foam material 11 is lined on the central portion.

FIG. 8 is a cross-sectional view of the upper portion of the protective cover 3 lined with the water swelling material 10, and the lower portion is also the same.

FIG. 9 is a transverse sectional view of the central portion of the protective cover 3 lined with the foam material 11.

When attaching the protective cover 3 lined with the water swelling material 10 above and below the center foam material 11 to the steel pipe pile 1, the anticorrosion cover 2 is wrapped around the surface of the steel pipe pile 1 with the anticorrosion tape 15. The inner layer of

Put the set plate 14 on the predetermined symmetrical position of the anticorrosion tape 15 wrapped around the anticorrosion area of the steel pipe pile 1, cover the protective covers 3 from both sides, and make sure that the seam between the protective covers 3 is at the set plate 14. , The gasket 13 is sandwiched between the flanges 4 of the same joint.

Then, when the flange 4 is tightened with the bolt 9, the water swelling material 10 and the foam material 11 of the intermediate layer can press the anticorrosion tape 15 against the steel pipe pile 1 to bring them into close contact.

After the protective cover 3 is fixed to the steel pipe pile 1 in this way, the clay-like finish is formed on the upper and lower end faces exposed to the outside of the protective cover 3, the water swelling material 10 and the anticorrosion tape 15 over the outer peripheral surface of the steel pipe pile 1 in the vicinity thereof. Material 16 is applied and completely closes the end face.

The finishing material 16 is made of an epoxy resin and has a property of being hardened even in water.

Thus, the attachment of the anticorrosion cover 2 to the steel pipe pile 1 is completed and the state shown in FIG. 1 is obtained.

The XX cross section of the end of the anticorrosion cover 2 in FIG. 1 is as shown in FIG. 10, and the anticorrosion tape 15 is formed on the surface of the steel pipe pile 1.
Is wound around to form an inner layer, and the water swelling material 10 lined on the protective cover 3 of the outer layer presses the anticorrosion tape 15 as an intermediate layer.

The finishing material 16 covers the end surfaces of the anticorrosion tape 15, the water swelling material 10, and the protective cover 3 having the three-layer structure in a watertight manner to prevent water from entering from the interface of each layer.

Since the anticorrosion cover 2 according to the present embodiment has the above-described structure and is attached to the steel pipe pile 1, the bolt 9 at the time of construction is used.
By tightening the protective cover 3 with the anti-corrosion tape 15, the anticorrosion tape 15 is adhered to the steel pipe pile 1 to block water and prevent corrosion of the steel pipe pile 1, and after the construction, it passes through the water guiding holes 7 provided in the upper and lower portions of the protective cover 3. When the water that has infiltrated is guided to the water guiding groove 8 and spreads to the outer surface of the water swelling material 10, the water swelling material 10 absorbs and expands, and the expansion pressure causes the anticorrosion tape 15 to further adhere to the steel pipe pile 1. And the anticorrosion effect can be enhanced, and long-term durability can also be obtained.

Therefore, at the time of construction, materials, structures, and construction methods in consideration of adhesion to the steel pipe pile 1 and sufficient corrosion resistance are not required, and low cost and simplification of construction can be achieved.

 It can also be installed on existing piles.

The cushioning effect is maintained by the foam material 11 of the intermediate layer and the water swelling material 10 having a high elastic modulus, the constraint of the load when only the foam material is used as the middle layer is relaxed, the degree of freedom in design is increased, and the water swelling material is increased. It is possible to set the arrangement of 10 and the foam material 11 and the occupied volume, etc. according to the application, the situation of the site, etc., and the optimum anticorrosion design can be done.

That is, when the entire pile is in the submerged area, the upper and lower parts may be the water swelling material layer as in this example, but when the upper part of the pile is in the air, only the submerged area is the water swelling material layer and the It is also conceivable to make the region a foam layer.

Further, since the foam material 11 is structured to be protected by the water swelling material 10, the durability against external damage is also improved.

In the above examples, the anticorrosion tape 15 was wrapped around the steel pipe pile 1, and the protective cover 3 having the water swelling material 10 and the foam material 11 lined thereon was applied and tightened. However, instead of the anticorrosion tape 15, It may be possible to further line the inner surface of the water swelling material 10 and the foam material 11 and integrally mold it, and by doing so, the work of winding the anticorrosion tape 15 around the steel pipe pile 1 at the site can be omitted. Can be further simplified.

Effect of the Invention Since the present invention is configured to combine the water swelling material and the foaming material in the intermediate layer of the anticorrosion cover, it is possible to obtain enhanced adhesion of the anticorrosion material to the underwater structure after construction, and anticorrosion property. Can be improved and durability can be maintained over a long period of time.

In addition, the construction can be simplified and the cost can be reduced.

 Construction is possible regardless of whether it is new or existing.

By combining a water-swelling material and a foaming material, the degree of freedom in design is increased, and the most effective optimum anticorrosion design for the anticorrosion specification conditions of the anticorrosion object is possible.

Further, the foaming material is protected by the water swelling material and durability against external damage can be increased.

[Brief description of drawings]

FIG. 1 is a perspective view of a steel pipe pile provided with an anticorrosion cover according to an embodiment of the present invention, FIG. 2 is a plan view of the protective cover of the anticorrosion cover, FIG. 3 is an inside view of the same, and FIG. 3 is a sectional view taken along line IV-IV, FIG. 5 is a sectional view taken along line VV of FIG. 3, FIG. 6 is a perspective view showing a combination of a protective cover, water swelling material and foam material, and FIG. 7 is an anticorrosion cover. Fig. 8 is an external view of Fig. VIII-VII in Fig. 7.
I sectional view, FIG. 9 is a IX-IX sectional view of FIG. 7, and FIG.
It is a XX sectional view of a figure. 1 ... Steel pipe pile, 2 ... corrosion protection cover, 3 ... protection cover,
4 ... Flange, 5 ... Bolt hole, 6 ... Reinforcement part, 7 ...
… Water guide hole, 8 …… Water guide groove, 9 …… Bolt, 10 …… Water swelling material, 11 …… Foam material, 13 …… Gasket, 14 …… Set plate, 15 …… Corrosion-proof tape, 16 …… Finishing material .

Claims (1)

(57) [Claims] 1. A structure of an anticorrosion cover attached to an anticorrosion area of an underwater structure such as a pile to be driven in water, an inner layer made of an anticorrosive material and in direct contact with the structure, an outer layer consisting of a protective cover, and the inner layer. A structure of an anticorrosion cover, comprising: a water-swelling material that occupies a predetermined range between the outer layer and the outer layer; and an intermediate layer made of a foam material that occupies the remaining range.