JPH0437973Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention relates to a corrosion-proof structure for columnar bodies such as steel pipe piles used in ports, rivers, etc.

[Conventional technology]

Conventionally, as a corrosion protection structure for columnar bodies such as steel pipe piles,
As disclosed in Japanese Unexamined Patent Publication No. 59-21833, a corrosion-proofing material is attached to the outer periphery of the steel pipe pile, and the surfaces of both ends of the cover plate made of glass fiber-reinforced thermoplastic resin are made of the same material as the cover plate. A protective cover formed by fixing angle members is wrapped around the outer periphery of the steel pipe pile so that the cover plate is in close contact with the corrosion-resistant material, and the angle members on both sides are connected with bolts and nuts. A corrosion protection structure is known in which a protective cover is attached to a steel pipe pile.

In addition, as an anti-corrosion structure for steel pipes used in pipelines, etc., as disclosed in Japanese Patent Application Laid-open No. 17093/1983, an anti-corrosion coating is provided on the outer surface of the steel pipe.
A corrosion-proofing agent or adhesive is provided on the outer surface of the end of the steel pipe, and an end-protecting coating made of polyethylene or the like is provided on the outer surface of the end of the steel pipe. A corrosion-proof structure in which the material is wrapped around the material and fixed with a fastener is known.

[The problem that the idea aims to solve]

In the case of the conventional columnar anti-corrosion structure, the cover plate is made of glass fiber-reinforced thermoplastic resin, and connecting members made of angle members made of the same material are fixed to both ends of the cover plate. Therefore, the elongation of the cover plate is small, so it is not possible to press the cover plate evenly around the entire circumference of the corrosion-resistant material.Furthermore, the strength of the connecting member is weak, so the cover plate must be strongly tightened to remove the corrosion-resistant material. It is not possible to make a strong pressure contact with the In addition, since the pressure contact force of the cover plate is small and the pressure contact force is not uniform over the entire circumference, seawater, etc. may enter the inside of the corrosion protection material, resulting in incomplete corrosion protection, and if used for a long time. There is a problem that the cover plate may slip off.

In addition, in the case of the conventional columnar corrosion-resistant structure, the cover plate has poor durability against ultraviolet rays and seawater, and seawater enters between the connecting ends of the cover plate, causing early deterioration of the corrosion-resistant material. There is.

Furthermore, even if the corrosion protection structure of steel pipes in the conventional pipelines etc. is adopted as the corrosion protection structure of columnar bodies, the material constituting the protective coating is ordinary polyethylene rather than low density polyethylene, so the extensibility of the protective coating is limited. Because it is small and the protective coating is simply wrapped around the edge of the anticorrosive coating and the anticorrosive coating or adhesive and fixed with a fastener, the protective coating can be applied evenly and strongly over the entire circumference. There are problems in that it is not possible to press the ends together, and that the end protection coating has poor durability against ultraviolet rays.

[Purpose of the invention, structure]

The purpose of this invention is to provide a corrosion-protective structure for a columnar body that can advantageously solve the above-mentioned problems. Corrosion-resistant metal connecting members 4 are fixed to both ends of a cover plate 3 made of a low-density polyethylene plate that is in contact with a corrosion-proofing material 2 and contains carbon black, an ultraviolet deterioration inhibitor, and an oxidation deterioration inhibitor. A protective cover 5 is disposed so as to surround the outer surface of the corrosion-resistant metal 2, and is secured to the cover plate 3 by a fastener 6 inserted across each of the opposing corrosion-resistant metal connecting members 4.
Corrosion protection for a columnar body characterized in that a water-absorbing and swelling waterproof material layer 22 is provided on at least one of the mutually overlapping ends of the protective cover 5, which is pressed against the outer surface of the corrosion-proofing material 2 under tension. It's in the structure.

〔Example〕

Next, this invention will be explained in detail using illustrated examples.

Figures 5 to 7 show an example of the protective cover 5 used when implementing this invention, and it is a low-density polyethylene plate containing carbon black, an ultraviolet deterioration inhibitor, and an oxidation deterioration inhibitor. One side of a corrosion-resistant metal connecting member 4 with an L-shaped cross section extending in the width direction of the cover 3 is overlapped and fixed with adhesive to both ends of a rectangular cover 3, and the other side of the connecting member 4 is is provided with a large number of through holes 7, and a water-absorbing and swelling water-stop material layer 22 is provided on the other outer surface of each connecting member 4, that is, the surface to be polymerized.
is attached.

FIG. 8 shows an example of a sheet-shaped corrosion-proofing material 2 used when implementing this invention, and shows a cushioning material layer 8 made of a sheet of open-cell polyethylene.
A corrosion-proofing layer 9 made of petrolatum is integrally laminated on the top and bottom to form a corrosion-proofing layer 2.

1 to 4 show a corrosion-protective structure of a columnar body according to an embodiment of this invention using the protective cover 5 shown in FIGS. 5 to 7 and the anti-corrosion 2 shown in FIG. 8. The anti-corrosion 2 is wrapped around the outer surface of the corrosion-protected area including the splash zone and the tidal zone of the columnar body 1 made of steel pipe piles that supports the structure 10 such as the concrete deck slab for a pier. Petrolatum-based corrosion protection layer 9 in corrosion protection 2
is closely attached to the outer surface of the columnar body 1, and a protective cover 5 is wrapped around the outer side of the corrosion-proofing material 2, as shown in FIG. In this state, a relatively large gap D is provided between the pair of opposing connecting members 4 in the protective cover 5.

Next, as shown in FIGS. 1 and 2, a plurality of fasteners 6 made of bolts are installed between the pair of opposing connecting members 4 and the rubber waterproof packing 11 interposed between them. inserted, and its fastener 6
is strongly tightened, the cover plate body 3 is expanded within its elastic limit, and the pair of connecting members 4 are pressed against the water-stop packing 11 via the water-absorbing and swelling water-stop material layer 22, and cover plate body 3
Due to the tightening force, the anticorrosive material 2 is pressed against the outer surface of the columnar body 1 over almost the entire surface.

9 to 11 show other examples of anti-corrosion interposed between the steel columnar body 1 and the cover plate 3 of the protective cover. In the case of FIG. 9, the columnar body A corrosion-proofing material 2 made of petrolatum-based paste is interposed between the first
In the case of Figure 0, an anticorrosive layer 9 made of petrolatum paste is provided between the columnar body 1 and the cover plate body 3.
In the case of FIG. 11, between the columnar body 1 and the cover plate 3, a corrosion-proofing layer 9 made of petrolatum-based paste and a water-absorbing and swelling waterproof material layer 12 are interposed. A corrosion-proofing material 2 composed of a water material layer 12 and a buffer material layer 8 made of open-cell polyethylene is interposed.

12 to 20 show the structure of the end of the protective cover 5 and the connecting structure of the end of the protective cover 5. A water-absorbing and swelling waterproof material layer 22 is provided on the inner surface of one side of the cover plate 3 and the outer surface of the other side of the cover plate 3 that protrudes beyond the connecting member 4, as shown in FIG. , cover plate 3
The respective water absorbing and swelling water stop material layers 22 at both ends of are arranged so that they are mutually superposed and the respective connecting members 4 are directly superposed and are fastened together by the fastener 6, or
Alternatively, as shown in FIG. 14, the water-absorbing and swelling water-stop material layers 22 at both ends of the cover plate body 3 are superposed on each other, and a rubber water-stop packing 11 is interposed between each connecting member 4 to tighten it. They are tightened and connected by a tool 6.

In the case of FIGS. 15 to 17, one end of the cover plate 3 is bent along the flange portion of one of the connecting members 4, but the other configurations are as follows.
This is the same as in the case shown in FIGS.

In the case of FIGS. 18 to 20, both ends of the cover plate 3 are arranged on the same plane as the end surface of the connecting member 4, and a polyethylene water stop plate is provided on the inner surface of one end of the cover plate 3. One side of the water stop plate 21 is polymerized and bonded by adhesive or heat fusion, and a water absorbing and swelling water stop material layer 22 is formed on the outer surface of the other side of the water stop plate 21 and the inner surface of the other end of the cover plate 3. However, the tightened and connected state is as shown in Figures 13 and 14.
This is the same as the case shown in the figure.

When implementing this idea, the low density polyethylene constituting the cover plate 3 may have a melt index of 0.05 to 0.5 g/10 min, a longitudinal elastic modulus, for example.
A material having a density of 2000 Kgf/cm ² , a specific gravity of 0.915 to 0.97, and containing carbon black is used, and the thickness of the cover plate 3 is set to, for example, 1.0 to 5.00 mm. Furthermore, carbon black, an ultraviolet deterioration inhibitor, and an oxidation deterioration inhibitor are added to the low-density polyethylene.

As the buffer material layer 8, open foamed urethane or nonwoven fabric may be used. Further, a sacrificial anode powder such as zinc powder or aluminum powder or cement may be added to the petrolatum-based anticorrosive layer.

As the anticorrosive material 2, a bituminous anticorrosive material or an underwater curing paint may be used, or a bituminous anticorrosive material to which sacrificial anode powder such as zinc powder or aluminum powder or cement is added. May be used. Furthermore, the anticorrosive material 2 may be provided integrally with the inner surface of the cover plate 3 in advance using an adhesive or the like.

The inner surfaces of both ends of the cover plate body 3 are made of stainless steel or FRP at positions facing the connecting member 4.
Alternatively, a splint made of a material such as polyethylene may be polymerized and fixed with bolts or other fixing means, or on the inner surface of one end of the cover plate 3.
One side of the splint in the width direction may be overlapped and fixed at a position facing the connecting member 4, and the other side of the splint may be made to protrude from the edge of the cover plate 3. Further, the structure of the end portion of the protective cover 5 may be any structure other than that shown in the drawings.

[Effect of idea]

According to this invention, a protective cover 5 is constructed by fixing corrosion-resistant metal connecting members 4 to both ends of a cover plate body 3 made of a low-density polyethylene plate having extremely high extensibility within the elastic limit, and The protective cover 5 is disposed on the outer surface of the sheet-like corrosion-proofing material 2 that is in contact with the periphery of the corrosion-protected part 1, and the protective cover 5 is tightened by being inserted across the corrosion-resistant metal connecting members 4 at both ends. Due to the tightening force of the tool 6, the cover plate body 3 is expanded within its elastic limit and brought into strong pressure contact with the corrosion protection material 2, so that the corrosion protection material 2 can be brought into close contact with the columnar body 1 over almost the entire surface. Therefore, it is possible to prevent seawater etc. from entering between the corrosion-proofing material 2 and the columnar body 1, and to completely protect the corrosion-proofing part of the columnar body 1 where the corrosion-proofing material is wrapped. However, almost the entire surface of the corrosion-proofing material 2 can be reliably brought into close contact, and since the cover plate 3 is elastically stretched to a large extent and a large tensile force is constantly acting on it, the fastener 6 can It is possible to eliminate the possibility that the protective cover 5 will loosen and fall.

Furthermore, since the cover plate 3 made of a low-density polyethylene plate contains carbon black, an ultraviolet deterioration inhibitor, and an oxidation deterioration inhibitor, the durability of the cover plate 3 against ultraviolet rays, seawater, etc. is significantly improved. Since the water-absorbing and swelling water-blocking material layer 22 is provided on at least one of the mutually overlapping ends of the protective cover 5, seawater is prevented from entering the anti-corrosion material 2 from the joints at both ends of the protective cover 5. Therefore, effects such as being able to further improve the corrosion resistance of the columnar body 1 can be obtained.

[Brief explanation of the drawing]

Figures 1 to 4 show one embodiment of this invention, in which Figure 1 is a side view of the columnar anti-corrosion structure, Figure 2 is its enlarged cross-sectional plan view, and Figure 3 is the structure. FIG. 4 is a partially vertical side view showing a state in which the corrosion protection device is attached to a columnar body supporting the corrosion protection device, and FIG. 4 is a cross sectional plan view showing the state before the protective cover wrapped around the corrosion protection device is tightened. 5 to 7 show the protective cover used in the embodiment of this invention, in which FIG. 5 is a front view, FIG. 6 is a cross-sectional plan view, and FIG. 7 is a view of the end of the protective cover. FIG. 3 is an enlarged cross-sectional plan view. FIG. 8 is a perspective view of the corrosion protection used in the embodiment of this invention, and FIGS. 9 to 11 are sectional views showing other examples of the corrosion protection interposed between the columnar body and the cover plate. be. Figures 12 to 20 show other examples of the joints at both ends of the protective cover, in which Figure 12 is an exploded plan view of the joints at both ends of the first example, and Figures 13 and 14 are FIG. 15 is an exploded plan view of a second example of the two-end joints, and FIGS. 16 and 17 show examples of the second example of the two-end joints. FIG. 18 is an exploded plan view of the both-end joint portions of the third example, and FIGS. 19 and 20 are cross-sectional plan views showing examples of joining the both-end joint portions of the third example. In the figure, 1 is a columnar body, 2 is a corrosion-proofing layer, 3 is a cover plate, 4 is a corrosion-resistant metal connecting member, 5 is a protective cover, 6 is a fastener, 8 is a buffer material layer, 9 is a corrosion-proofing layer, 11 is rubber water-stop packing, 12 is a water-absorbing and swelling water-stop material layer, 13 is a splint, 14 is a countersunk bolt,
15 is a nut, 16 is a flange, and 22 is a water absorbing and swelling water stop material layer.

Claims (1)

[Scope of utility model registration request] A sheet-like anticorrosive material 2 is brought into contact around the corrosion-protected portion of the columnar body 1, and both ends of a cover plate body 3 made of a low-density polyethylene plate containing carbon black, an ultraviolet deterioration inhibitor, and an oxidation deterioration inhibitor. A protective cover 5 configured by fixing a corrosion-resistant metal connecting member 4 to a portion thereof is disposed so as to surround the outer surface of the corrosion-resistant metal connecting member 2, and the fastener is inserted through each of the facing corrosion-resistant metal connecting members 4. 6, the cover plate body 3 is tensioned and pressed against the outer surface of the corrosion-proofing material 2,
Corrosion-proof structure of a columnar body, characterized in that a water-absorbing, swelling, and water-stopping material layer 22 is provided on at least one of the mutually overlapping ends of the protective cover 5.