JPH01182409A - Method of retaining soil using decorative steel material - Google Patents

Abstract

PURPOSE:To obtain a decorative steel material which can be installed at a job-site by forming a mechanical plating film on the outer surface of the steel material directly or indirectly through a plated layer, and thereafter, by forming a decorative layer on the outer surface of the steel material after the outer surface being chemically treated so as to form a soil retaining steel material. CONSTITUTION:A mechanical plating film 3 is formed on the outer surface of a steel material 1, and a decorative material 2 is formed over the film 3 so as to form a decorative steel material to be used for soil retaining construction, which can be installed at a job site and can sustain its aesthetical appearance for a long term. Further, the mechanical plating film 3 is formed such that shots which are obtained by coating Fe-Zn alloy or Fe-Zn-Al alloy on steel spherical cores are sprayed onto the outer surfaces of the steel material 1 so as to mechanically coat the Fe-Zn alloy or the Fe-Zn-Al alloy on the outer surface of the steel material 1. Then, the outer surface of the mechanical plating film is chemically treated. It is noted that the film is coated on the outer surface of the steel material through the intermediary of a plated layer.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to the so-called earth retaining method used in bank protection work, landslide prevention work, housing land development work, etc. Concerning an earth retaining method that takes care not to damage the surrounding landscape.

(Background of the Invention) In recent years, environmental conservation and maintenance of the scenery of scenic spots have become more important, and even in the above-mentioned construction work, the aesthetic appearance after construction is often an issue. For example, in bank protection work for rivers and lakes,
It is not enough to simply achieve the construction purpose of earth retaining, but after construction, consideration must be given to ensure that the parts that are visible to the public blend in well with the surrounding environment.

On the other hand, in order to reduce construction costs, it is necessary to use materials as cheap as possible and to proceed with construction efficiently. Civil engineering materials that meet these requirements include steel sheet piles, steel pipe piles, and shaped steel. However, these steel materials themselves develop rust, which is characteristic of steel materials, in environments where civil engineering works are carried out, and they do not maintain their aesthetic appearance for a long time after construction.

Therefore, civil engineering steel materials are sometimes subjected to some kind of surface treatment to prevent rust and maintain their aesthetic appearance, but as will be explained later, the methods proposed so far have either been ineffective or require too much effort to be put into practical use. There is no sex.

Therefore, there is currently a strong demand for an earth retaining method that is easy to construct and can maintain its aesthetic appearance over a long period of time.

(Prior Art) Civil engineering steel materials are, in principle, used as hot-rolled without any special surface treatment. However, when used in areas where corrosion is particularly severe, such as on the coast, Zn plating or application of anti-corrosion paint is sometimes carried out as anti-rust treatment. However, such surface treatments are not particularly aesthetically pleasing and do not match the surrounding environment of the construction site. The silver-white color of Zn plating and the vermilion color of anti-rust coating often stand out from the surrounding natural environment and spoil the landscape.

One possible way to solve the above problem is to cover the surface of the steel material, especially the parts that are visible to the public after construction, with a decorative material that matches the surrounding environment. There are many types of such decorative materials, such as plastic mortar such as polymer cement mortar (PC cup, resin mortar, etc.), artificial stone panels, synthetic resins, and wood. Even if it is affixed to the sheet pile in advance, its adhesive strength is weak, so when steel is cast during earth retaining work, the decorative material will peel off due to shock and vibration.Even if the decorative material remains after construction, its durability will be affected. are small and will peel off in a short period of time.Therefore, when using such decorative materials, it is necessary to first pour bare steel, complete the construction, and then reapply the decorative finish. It won't happen.

FIG. 5 is a conceptual diagram illustrating such conventional earth retaining construction using decorative materials. That is, after completing the earth retaining work by installing steel materials (for example, steel sheet piles) 10 as shown in Figure 5A, the water is dammed up as shown in the opening of the figure, and formwork and scaffolding are erected to make up the structure. The material 11 is injected, pasted, or sprayed.

Even with this extremely time-consuming construction work, the inherent weak adhesive strength between the steel and decorative materials has not been resolved, so over time the decorative materials will peel off and rust will appear in those areas. It seriously spoils the aesthetic appearance.

In short, until now, there has been no decorative material for civil engineering that can withstand pouring and other installation work at construction sites and maintain its aesthetic appearance over a long period of time. It has not fully achieved its purpose.

(Problems to be Solved by the Invention) An object of the present invention is to provide a new construction method, especially an earth retaining construction method, for constructing decorative steel materials in places that are visible to the public after construction. This was done with the aim of maintaining its decorative quality over a long period of time and contributing to environmental conservation.

(Means for Solving the Problems) The gist of the present invention lies in the following earth retaining methods (1) to (3).

(At least a part of the surface of 11 is Fe-
An earth retaining method characterized by installing a decorative steel material covered with a mechanical plating film of Zn alloy or Fe-Zn-An alloy and a decorative material layer formed on the film.

(2) Zn, Aj!, whose surface is roughened at least in part by blasting and subjected to chemical conversion treatment; Or Zn-Aj! An earth retaining method characterized by installing steel covered with an alloy plating layer and a decorative material formed on the plating layer.

(3) At least a part of the surface is Zn, Aj! Or Zn-/F! An alloy plating layer and a Fe-Zn alloy or Fe-Zn-Aj formed on the plating layer and subjected to chemical conversion treatment! An earth retaining method characterized by installing a decorative steel material covered with an alloy mechanical plating film and a decorative material layer formed on the film.

Before explaining each construction method of the present invention, the knowledge that formed the basis of the present invention will be described.

Conventionally, the reason why it has not been possible to construct steel materials to which decorative materials have been applied in advance in the same way as general steel materials is because the durability of the adhesive force between the steel materials and the decorative materials is weak, as described above. Even if a decorative material such as the one described above is attached to as-rolled steel material or to steel material plated with Zn, Al, etc., the adhesive durability decreases, especially during pouring work during construction. However, if the adhesive strength is increased to improve durability and to withstand installation work, the work can be carried out in the same way as when using ordinary steel materials, and the total cost of work can be significantly reduced.

The present inventor focused on applying surface treatment technology, which has recently made remarkable progress, to the production of steel materials for civil engineering, and as a result of numerous tests, the inventor applied a special surface treatment to the surface of the steel material before pasting the decorative material. It was confirmed that the above-mentioned adhesive strength and adhesive durability can be greatly improved by applying the adhesive. Moreover, this surface treatment also contributes to rust prevention of steel materials, extending the life of steel materials in harsh corrosive environments.

First, the construction method of the first invention of the present application will be explained.

FIG. 1 is a schematic cross-sectional view of a steel material used in this construction method. As shown in FIG. 1, a mechanical plating film 3 is provided on the surface of a steel material 1, and a decorative material 2 is placed on top of the mechanical plating film 3. This mechanical plating film is a steel ball core material made of Fe-
Zn alloy or Fe-Zn-Ai gold alloy coated shot (sometimes called two grains) is sprayed onto the steel surface to form Fe-Zn alloy or Fe-Zn-//! The alloy is mechanically applied. The basic technology of this mechanical plating is disclosed in Japanese Patent Publication No. 59-9312, but the mechanical plating used in the present invention is not limited to that introduced in the above publication, for example, Zn grains and Fe grains. For example, how to mix and spray with
Any method that can mechanically form a predetermined alloy film on the surface of the steel material can be used. We chose Fe-Zn alloy or Pe-Zn-A1 alloy as the mechanical plating film because these films have excellent corrosion resistance and are inexpensive, and the mechanical plating technology has also been completed. It is from. Furthermore, Fe-Zn
Although it is an alloy, since it is mechanically plated, the film often contains a phase of pure Zn. In the present invention, such a film is also referred to as a mechanical plating alloy film.

The film formed by mechanical plating is
Compared to metal films obtained by electroplating or hot-dip metal plating (dobuzuke plating), the film itself is porous and has a large amount of surface roughness. Roughness is RIII
m is 5 to 20. Such a surface has extremely good adhesion to the above-mentioned decorative materials. For example, whether you are spray painting a cement-based decorative material or using an adhesive to affix a panel of wood or artificial stone, the mechanical plating film is compatible with cement mortar and adhesives.
It has good wettability, and its moderate roughness gives it an anchoring effect, giving it sufficient workability as a steel material for civil engineering.

The mechanical plating method used as a surface treatment is a so-called dry plating method that does not use aqueous solution or heat like electroplating or hot-dip plating.If the equipment is devised, it is not only possible to continuously plate long materials, but also suitable for civil engineering construction sites. It has many advantages such as being able to perform brating processing.

However, as mentioned above, since the film is porous, the corrosion resistance is somewhat inferior to that of ordinary plating. In order to improve this point, chemical conversion treatment is applied to the mechanical plating film.

A suitable chemical conversion treatment is chromate treatment or phosphate treatment, and when this treatment is performed, the coating is impregnated with a chromate or phosphate treatment agent, and corrosion resistance is dramatically improved. In particular, the present applicant and others previously proposed a chemical conversion treatment method for Fe-Zn mechanical plating film (Japanese Unexamined Patent Application Publication No. 1983-1989).
The aqueous chromate treatment (see Japanese Patent No. 93383) is most suitable for the chemical conversion treatment here. That is, it is immersed in an aqueous solution containing 0.1 to 50 g/1 of a chromic acid compound and 0.01 to 5 g/2 of sulfuric acid, or coated or sprayed with this solution.

The mechanical plating film that has been chemically treated as described above has excellent corrosion resistance by itself, so even if the decorative material on the steel surface cracks or is partially missing during long-term use. , there is no risk of the base rusting rapidly and damaging the aesthetics.

The thickness of the mechanical plating film can be selected depending on the environment in which the steel is used (corrosion conditions, etc.);
The thickness should be approximately 5 μm.

Various materials can be used as the decorative material 2 depending on the purpose of use of the steel material, especially the environment in which earth retaining work is performed. For example, for bank protection work around a dam, a cement-based decorative material that matches the dam's concrete structure is appropriate, while for scenic spots such as lakes, panels of natural stone, artificial stone similar to it, or wood-based materials may be selected. It will be done. Examples of such decorative materials are listed below.

■ Wooden boards such as cedar, cypress, and paulownia, plywood, etc. ■ Non-ferrous metals such as aluminum, copper, titanium, stainless steel, etc. thin plates, ■ Synthetic resins such as acrylic resin, epoxy resin, urethane resin, etc. ■ Plastic mortar polymer cents Mortar, resin mortar, etc. Other natural stone, artificial stone panels, crushed stone mixture, ceramic tiles,
It is of course possible to use these decorative materials not only alone, but also by overlapping them or by changing the type depending on the part of the steel material.

For example, when using plastic mortar as a decorative material, this mortar is applied by spraying with various types of guns such as a mortar gun, but if a decorative coating film is further applied to the surface using various paints such as urethane resin paint, it is possible to use the mortar. You can add any pattern that blends well with your environment. Plastic mortar is extremely strong against bending, tension, impact, etc., and its water permeability is also much lower than that of ordinary cement mortar.Coupled with its good adhesion to steel materials, the coating layer is It can prevent damage such as cracking and peeling as well as corrosion of steel materials over a long period of time, and can achieve excellent durability.

If a panel of wood or artificial stone is used as the decorative material, for example, it will be adhered to the underlying mechanical plating film using a suitable adhesive. As an adhesive,
The above-mentioned plastic mortar can be used, and acrylic adhesives, epoxy adhesives, polyimide adhesives, etc. can also be used.

Next, the construction method of the second invention of the present application will be explained.

FIG. 2 is a schematic cross-sectional view of the steel used in this construction method. As in FIG. 1, there are a steel material 1 and a decorative material 2, but here there is a plating layer 4 between them.

This plating layer is made of Zn, Aj! , or Zn-Aj
! Alloy normal (not mechanical plating)
It is a plating layer. This is applied to the steel surface by common methods such as hot-dip plating, electroplating, or thermal spraying. The thickness may be approximately 20 to 100 μm.

This plating layer 4 has poor adhesion to decorative materials as it is. In order to improve this point in the present invention, this plating layer is given an appropriate roughness similar to that of the mechanical plating film described above.

As a means for this purpose, shot blasting is a practical method for industrial production. That is, after the plating process, a blasting material such as micro steel balls or sand is sprayed to make at least the surface of the plating layer rough to about R1, 10 to 40. At this time, the two particles mentioned above may be used as the blasting material, or a mixture of steel balls and Zn or Al small balls may be used.
The effect of mechanical plating can also be used in combination.

In this case as well, the plating layer is subjected to chemical conversion treatment in order to improve the corrosion resistance of the base itself. The type of chemical conversion treatment and treatment method may also be the same as described above.

Further, the decorative material applied to the base thus formed is also the same as that described above.

Finally, the construction method of the third invention of the present application will be described.

Figure 3 shows the steel materials used in this method, Figures 2 and 3.
FIG. Here, a plating layer 4 and a mechanical plating film 3 are present between the steel material 1 and the decorative material 2. That is, the steel material shown in FIG. 3 is intended to achieve the combined effect of the steel materials shown in FIGS. 1 and 2. The plating layer 4 is made of the above-mentioned Zn, l/! Or Zn-An! This is a normal plating layer of alloy. However, in this case, the thickness may be thinner than in the case of FIG. 2, and chemical conversion treatment is not necessary.

The mechanical plating film 3 in FIG. 3 is formed in the same manner as in FIG. 1, and is subjected to a chemical conversion treatment. Then, the above-mentioned decorative material is layered on top of this.

Although the steel materials shown in FIGS. 1 to 3 have been described above, it is not necessary to coat the entire surface of the steel material with such a decorative material. That is, after the construction of the earth retaining is completed, it is sufficient to cover only the parts that are likely to be seen by the public (in the case of bank protection work, the parts that are above the water surface) with decorative material. However, in order to prevent corrosion of steel materials, it is recommended that even just a surface treatment be applied to the entire surface.

Now, the construction of earth retaining using decorative steel materials as mentioned above,
For example, driving (placing) using pressure force, vibration, and impact
In the present invention, the installation of steel can be carried out by spiral descent, excavation installation using jets, etc., and a combination of these methods. In the present invention, the installation of steel can be carried out by using various construction methods such as those described above to install decorative steel for the purpose of retaining earth. It means to arrange it in such a way.

The adhesive durability of the decorative steel materials used in the method of the present invention is extremely high against shocks, vibrations, and collisions with earth and sand during the installation work as described above, and there is no possibility that the decorative material will peel off during the installation work. do not have.

Therefore, if the decorative steel material is manufactured in a factory or in advance at a construction site, the installation work itself can be carried out in the same way as in the case of ordinary bare steel material.

Fig. 4 explains the earth retaining method of the present invention. As shown in Fig. 4A, a steel material 10 with a decorative material 11 applied in advance is installed, and after the installation is completed, concrete 12 is poured on the upper edge of the opening in the figure. The construction work will be completed.

(Example) As shown in Table 1, five types of surface treatments were applied to the steel plate,
A test piece was prepared by adhering cypress wood and polymer cement mortar (PCM) as decorative materials.
Various tests shown in the table were conducted.

The steel plate is made of SS41 material with a size of 3 x 25 x 100 mm, and the decorative cypress wood (5 x 20 x 100
m) was crimped using a two-component modified acrylic adhesive (trade name Bisset 71) at a pressing force of 2 to 3 kg/cm''.

PCM is applied by spraying with a mortar gun to a thickness of approximately 2 to 3 cm.
mm.

The test method shown in Table 1 is as follows.

20°C/8 (according to JIS K-6857)
After drying at 5% RH and 50°C for 24 hours, 29 hours, 72 hours, and 48 hours, the pieces were left indoors for 7 days and peel strength was measured.

Invasion of Supervising Stars (Japan Adhesive Association: Adhesive Durability Research Committee) Soaking in 60±3°C warm water for 3 days and opening at 60±3°C 4
Peel strength was measured every 1, 5, and 10 cycles, with days being one cycle.

From the test results in Table 1, it can be seen that the decorative material was attached to a steel plate that was subjected to surface treatment according to the present invention (test specimens ASB and C
) outperforms test piece E, especially in the dry-wet cyclic test. In addition, D is a steel material whose surface is simply coated with Sigitplast, and E is a steel material which is only hot-dip galvanized.

Next, as shown in Table 2, test piece A of Table 1 was applied to the steel sheet pile.
, the same treatment as B (sheet piles F and G) was carried out, and the installation was carried out corresponding to the construction conditions of actual earth retaining work, and the situation at the time of installation and 1.
Changes after 2 years and 2 years were investigated. For comparison,
Table 2 also shows the results for the zinc-plated material with °I) CM applied (H), the normal galvanized material (1), the rust-preventing coated material (J), and the uncoated material (K).

Installation was carried out using a vibration method using a vibrohammer.

From the results in Table 2, it can be seen that according to the earth retaining method of the present invention, not only is there no damage to the decorative material during installation work, but there is also minimal deterioration over time after installation.

(Effect of the invention) As shown in the examples, according to the construction method of the present invention that uses steel materials to which decorative materials are firmly adhered, the decorative steel materials to which the decorative materials are attached in advance can be simply installed as usual. Earth retaining can be done to harmonize with the surrounding landscape. In other words, it is no longer necessary to drain water again, erect scaffolding and formwork, and perform decorative finishing work after the installation work is completed, as was the case in the past, and the effects of reducing construction costs and shortening the construction period are immeasurable.

Furthermore, the steel constructed using the method of the present invention far exceeds conventional steel in terms of corrosion resistance, so it can be effective for a long period of time both for its original purpose of retaining earth and for preserving the landscape. .

[Brief explanation of the drawing]

1 to 3 are schematic cross-sectional views of decorative steel materials used in the earth retaining method of the present invention. FIG. 4 is a schematic diagram for explaining the earth retaining method of the present invention, and FIG. 5 is a schematic diagram for explaining the conventional earth retaining method using decorative materials. 1 Nu Fushi 1 no (A) Convex (A) 4th ■ (B) 5th figure (B)

Claims (3)

[Claims] (1) At least a part of the surface is Fe-
An earth retaining method characterized by installing a decorative steel material covered with a mechanical plating film of Zn alloy or Fe-Zn-Al alloy and a decorative material layer formed on this film. (2) Zn, Al or Zn whose surface has been roughened by blasting and chemically treated, at least in part
- An earth retaining method characterized by installing a steel material covered with an Al alloy plating layer and a decorative material formed on the plating layer. (3) At least a part of the surface is Zn, Al or Z
A plating layer of n-Al alloy, and a Fe-Zn alloy or Fe-Z formed on this plating layer and subjected to chemical conversion treatment.
An earth retaining method characterized by installing a decorative steel material covered with a mechanical plating film of n-Al alloy and a decorative material layer formed on the film.