JPH0340918Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention relates to a corrosion-protective structure for members driven into the underwater ground, such as existing steel pipe piles and steel sheet piles.

[Prior art]

Conventionally, as an anti-corrosion structure for members driven into the submerged ground such as steel pipe piles and steel sheet piles, as disclosed in Japanese Patent Application Laid-open No. 58-29916, anti-corrosion was applied as the innermost layer on the surface of the members driven into the submerged ground. In addition to providing a main anti-corrosion layer, a buffer material layer to withstand impact is provided as an intermediate layer, and a plate-shaped or sheet-shaped protective cover layer made of reinforced plastic or corrosion-resistant metal is provided as the outermost layer. Layered anti-corrosion structures are known.

In addition, when fixing the anti-corrosion body to a steel pipe pile, (1) is a fixing means that is tightened and fixed with a large number of bolts and nuts through a flange that is integrally provided with a protective cover layer; (2)
A fixing means is adopted in which several bands are placed at intervals in the vertical direction from the outside of the protective cover, and when the three-layer anti-corrosion body is fixed to the steel sheet pile, (3) A fixing method is adopted in which the anti-corrosion body is tightened and fixed using a large number of stud bolts planted in the steel sheet pile, and (4) a fixing means is adopted in which the anti-corrosion body is temporarily fixed to the steel sheet pile and then fixed with a drive pin from the outside of the anti-corrosion body. ing.

[Problem that the invention attempts to solve]

However, in the case of the fixing means (1) and (2) above, when the distance between the bolts or tightening bands is large or the tightening force is insufficient, a gap may be created between the corrosion protector and the surface of the steel pipe pile. seawater may enter the gaps, making it impossible to achieve sufficient corrosion protection. If you reduce the distance between bolts and tightening bands,
Although it can counteract the intrusion of seawater to some extent, it increases the cost of materials and construction.

On the other hand, when driving steel sheet piles, the steel sheet piles are rarely installed as planned, and construction errors such as tilting in the front and rear directions, tilting in the left and right directions, twisting, elongation, and shrinkage occur in the steel sheet piles. The reality is that this is unavoidable, and the joint fitting portion of steel sheet piles has a complicated shape, unlike webs and flanges. For this reason, when the anti-corrosion body is fixed to the steel sheet pile wall using the fixing means (3) and (4) above, a gap is likely to be created between the anti-corrosion body and the surface of the steel sheet pile wall, and seawater may infiltrate into that gap. Therefore, sufficient anticorrosion effect cannot be exhibited. In addition, reducing the spacing between stud bolts and drive pins can prevent seawater from entering to some extent, but this increases material and construction costs, resulting in higher costs.

Furthermore, if the surfaces of steel pipe piles and steel sheet pile walls are uneven due to corrosion, gaps will form between the depressions and the anti-corrosion body, and seawater may infiltrate into these gaps, so sufficient anti-corrosion effects cannot be achieved. You can't expect it.

[Purpose of the invention, structure]

The purpose of this invention is to provide an anti-corrosion structure for a member driven into the submerged ground, which can advantageously solve the above-mentioned problems. A water-absorbing, swelling, sacrificial anode-forming anticorrosive layer 2 is provided on the surface, which is formed by adding a sacrificial anode-forming powder to a water-absorbing, swelling, viscosoftening, anticorrosive.
The anti-corrosion structure of the member for driving into the submerged ground is characterized in that the anti-corrosion layer 2 for forming a sacrificial anode by water absorption and swelling is covered with a protective cover 3 made of a thin plate of plastic or corrosion-resistant metal.

〔Example〕

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

FIG. 5 and FIG. 6 show the anti-corrosion cover 4 used in the embodiment of this invention,
A cushioning material layer 5 made of foamed rubber or synthetic resin foam such as foamed polyethylene is integrally provided on the inner surface of the protective cover 3 made of a thin plate of polyethylene or other plastic or a thin plate of corrosion-resistant metal such as stainless steel. The inner surface of 5 is made of urethane-based water-absorbing, swelling and softening anti-corrosive material, zinc powder,
A water-absorbing, swelling sacrificial anode-forming anticorrosive layer 2, which is formed by adding and mixing a sacrificial anode-forming powder such as aluminum powder, is integrally provided, and the water-absorbing, swelling, sacrificial anode-forming anticorrosive layer 2, protective cover 3, and buffer material layer are integrally provided. 5 are aligned so that they are located on the same plane, and the other ends of the water absorption swelling sacrificial anode forming anticorrosive layer 2 and the buffer material layer 5 in the left and right direction are arranged on the same plane. , and the upper and lower ends of the other end of the protective cover 3 in the left and right direction are also aligned.
It is aligned so as to be located on the same plane as the other end of the water absorption swelling sacrificial anode forming anticorrosion layer 2 and the buffer material layer 5.

A presser plate 6 and a flange 7 are arranged in series at the vertically intermediate portion of the other end of the protective cover 3 in the left-right direction, and a presser plate 6 and a flange 7 are provided in a row in the vertical direction on the outer surface of the protective cover 3 at a position slightly away from the bottom of one end in the left-right direction. Extending L-shaped cross-section stainless steel connecting fitting 8
A corrosion-resistant material, for example, a stainless steel connecting fitting 9, which has an L-shaped cross section and is polymerized on one side and fixed with an adhesive, an adhesive, or a screw (not shown), and further extends vertically to the presser plate 6 and flange 7. are polymerized and fixed with adhesive or screws (not shown), and a large number of through-holes 10 for bolt insertion are provided on the sides perpendicular to the protective cover 3 of each of the connecting fittings 8 and 9 and on the flange 7. ing.

As the water-absorbing, swelling and viscosoftening anti-corrosive material constituting the water-absorbing and swelling sacrificial anode-forming anti-corrosive layer 2, for example, Chemiguard U-1 (manufactured by Sanyo Kasei KK) is used.

FIGS. 1 to 4 show a corrosion-proof structure of a member driven into the submerged ground according to an embodiment of this invention using the anti-corrosion cover 4, which supports a structure 11 such as a concrete deck slab for a pier. The anti-corrosion cover 4 is wrapped around the outer surface of the area to be protected from corrosion, including the splash zone and the tidal zone, in the steel submerged ground driving member made of steel pipe piles. A large number of bolts 12 are inserted through the bolts 12, and the anti-corrosion cover 4 is tightened by the bolts 12, and the anti-corrosion layer 2 in the anti-corrosion cover 4, which absorbs water and swells to form a sacrificial anode, is applied to the outer surface of the steel submerged ground driving member 1. It is pressed. Furthermore, stainless steel tightening bands 13 are wound around the outer surfaces of the upper and lower ends of the anti-corrosion cover 4 wrapped around the steel bottom driving member 1 and fixed with bolts 14 .

When implementing this invention, the buffer material layer 5 is omitted, and a sacrificial anode forming powder such as zinc powder or aluminum powder is added to and mixed with a urethane-based water-absorbing, swelling and viscosifying preventive material as shown in FIG. A water-absorbing, swelling, sacrificial anode-forming, anticorrosive layer 2 may be fixed to the inner surface of the protective cover 3. Alternatively, as shown in FIG. Before the food layer 15 hardens, a sacrificial anode-forming powder is sprinkled on the inner surface of the water-absorbing, swelling, viscosoftening, anticorrosive layer 15, thereby forming the water-absorbing, swelling, viscosoftening, anticorrosive layer 15 and the sacrificial anode-forming powder-containing layer 16. A water-absorbing, swelling, sacrificial anode-forming anticorrosive layer 2 may be formed.

Furthermore, as shown in FIG. 9, a water absorption swelling sacrificial anode forming anticorrosive layer 2 consisting of the water absorption swelling viscosoftening anticorrosive layer 15 and sacrificial anode forming powder containing layer 16 as described above and a protective cover 3 are provided. Between the cushioning material layer 5
may be interposed integrally.

As shown in FIGS. 1, 6, and 9, if a cushioning material layer 5 is provided inside the protective cover 3,
Impact force when driftwood or the like collides with the protective cover 3 is buffered and dispersed by the buffer material layer 5 and transmitted to the water-absorbing, swelling, sacrificial anode-forming, anti-corrosion layer 2 and the water-absorbing, swelling, viscosoftening, anti-corrosion layer 15. Therefore, it is possible to eliminate the possibility that the water-absorbing swelling sacrificial anode-forming anticorrosive layer 2 and the water-absorbing swelling viscosoftening anticorrosive layer 15 are partially crushed by excessive impact force.

As a means for tightening and fixing the anti-corrosion cover to the steel pipe pile, any means other than those shown may be employed.

In addition, the protective cover 3 is made of polyethylene, which has improved durability by containing an ultraviolet deterioration inhibitor such as carbon black and an oxidation deterioration inhibitor such as a phenol or sulfur compound, especially in its excellent resistance to environmental stress cracking. Low density polyethylene is preferred.

[Effect of idea]

According to this invention, a corrosion-proof cover 4 having a water-absorbing, swelling, sacrificial anode-forming corrosion-proof layer 2 and a protective cover 3 is provided.
When attached to the surface of the steel submerged ground driving member 1, even if there is a gap between a part of the water absorption swelling sacrificial anode forming anticorrosive layer 2 and the steel submerged subsurface ground driving member 1, water absorption will not occur. When the swelling sacrificial anode-forming corrosion-resistant layer 2 absorbs water in seawater, it swells and becomes viscous. adheres to the surface,
Therefore, the gap between the inner surface of the water-absorbing swelling sacrificial anode-forming anticorrosive layer 2 and the surface of the steel submerged subgrade member 1 is automatically eliminated, and the surface of the steel submerged subgrade member 1 is reliably protected from corrosion. When the sacrificial anode forming anticorrosive layer 2 absorbs water and swells, a microcurrent is generated between the sacrificial anode forming powder and the steel underwater ground driving member 1, and the sacrificial anode forming powder turns into steel. Since it melts out earlier and so-called cathodic protection is performed, effects such as significantly improving the corrosion resistance of the steel submerged underground member 1 can be obtained.

[Brief explanation of the drawing]

The drawings show an embodiment of this invention,
Figure 1 is a cross-sectional plan view showing the anti-corrosion structure of the underwater foundation driving member, and Figure 2 is a partially vertical side view showing the state in which a retaining plate is attached to the steel underwater foundation driving member that supports the structure. , FIG. 3 is an enlarged side view of a part of FIG. 2, FIG. 4 is an enlarged sectional view taken along the line A-A in FIG. 3, and FIG.
FIG. 6 is a sectional view taken along the line B--B in FIG. 5. 7 to 9 are cross-sectional views showing other examples of the anti-corrosion structure of the submerged ground driving member of this invention. In the figure, 1 is a submerged ground driving member, 2 is a water absorption swelling sacrificial anode forming anticorrosion layer, 3 is a protective cover, and 4
is an anti-corrosion cover, 5 is a buffer layer, 7 is a flange, 8
9 is a connecting fitting, 12 is a bolt, 13 is a tightening band, 14 is a bolt, 15 is a water-absorbing, swelling and softening anticorrosive layer, and 16 is a sacrificial anode-forming powder-containing layer.

Claims (1)

[Scope of utility model registration request] A water-absorbing, swelling sacrificial anode-forming anti-corrosion layer 2 is provided on the surface of the steel submerged ground driving member 1, and the water-absorbing, swelling, sacrificial anode-forming anti-corrosion layer 2 is formed by adding sacrificial anode-forming powder to a water-absorbing, swelling, viscosoftening, anti-corrosive material. An anti-corrosion structure for a member driven into the submerged ground, characterized in that a formed anti-corrosion layer 2 is covered with a protective cover 3 made of a thin plate of plastic or corrosion-resistant metal.