JPS59224719A - Highly corrosion-resistant covered steel sheet pile - Google Patents

Abstract

PURPOSE:To raise the durability of a steel sheet pile to be driven into the bottom ground under water by covering the ebb and flow zone and flash zone at least of the steel sheet pile with a synthetic resin having a specific tensile elasticity modulus in advance. CONSTITUTION:At least ebb and flow zone and flash zone of a steel sheet pile 2 is covered with a thermoplastic resin, e.g., polyethylene, polypropylene, vinyl acetate, vinyl chloride, etc., or a thermosetting resin, e.g., urethane resin, etc., as a synthetic resin having a tensile elasticity modulus of 0.8X10<3>-15X10<3>kg/cm<2> to form a covering layer 5. Because such a highly corrosion-resistant covering is provided to the steel sheet pile, damage to the steel sheet pile during the construction work can be prevented and the corrosion resistance of the pile can be maintained for a long period of time.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a structure in which at least the tidal zone and the splash zone of the steel sheet piles that are inserted into the underwater ground in order to build commercial structures in water areas such as ports and rivers are pre-tensioned. De1 sex rate is 0.8 x 10'~15 x 10°lk buttock J
Synthesis of (I) Covered by fatty acid!
The characteristics of corrosion protection are related to steel sheet piles.

Conventionally, steel sheet piles for civil engineering and construction have been used for the purpose of revetment of rivers + shores, ports, etc. by driving a large number of steel sheet piles in succession to form corrugated fences. The RIS2+E was used for the purpose of fixing the ground at construction sites and other sites to prevent mud and sand from flowing into the work site and from collapsing.

These steel sheet piles are exposed to water such as river water, wastewater, rainwater, seawater, etc., in the outdoor natural environment, and sunlight.
Also, since the inscribed 5 i is in contact with earth, sand, mud, and rubble,
The above-mentioned corrosion occurs extremely easily in environmental places where running water, waves, etc., the atmosphere, and sunlight interact with each other, such as ports and estuaries. This is because no effective corrosion prevention measures have been taken in the past.

Therefore, even if conventional steel sheet piles are made of corrosion-resistant copper phase, they are susceptible to Dt-corrosion under the above-mentioned natural conditions. It is often the case that the period of use becomes relatively short and cannot be used for a long period of time (for example, longer than about 2041).

- In the past, it was common for counterfeit sheet piles used in ports and river areas to be used bare, but in recent years, long-term durability of 40 to 50 years has been required for structures in ports and river areas. Therefore, it has become necessary for steel sheet piles, which are conveniently used in these severe corrosive environments, to take 1υ-grade measures to maintain long-term corrosion protection.

Conventionally, the method for preventing corrosion of steel sheet piles is 1. A method of applying tar-epoxy coating, a method of applying cathodic protection.

Methods of applying mortar coatings (for example, FBI' force and shovel method, etc.) are known.

However, Taref 1? In the case of the method of applying oxidized paint, it is complicated because it is necessary to apply 141 every few years, and long-term performance cannot be expected, and it is necessary to apply 141 paint every few years. Even if tare epoxy paint is applied, the paint film is soft and easily scratched during drilling or driving, and after the paint is applied, driftwood etc. collide with it. When applying tar-epokine coating after the TC steel sheet pile is placed, it is likely that the steel sheet pile will corrode from the uneven part. It protects only the upper part of the water. 3+ (If applying to the underwater part of the sheet pile, drainage treatment is required, which increases the cost.

In addition, in the case of a method without applying anticorrosion,
j Due to the gas-chemical mechanism, corrosion prevention effects are difficult to exhibit in areas that protrude into the air from the water surface, such as in the splash zone and tidal zone, where steel corrosion is most likely to occur.

The I+4 eclipse velocity of the copper phase in harbors and river waters is determined by the droplet zone (from the estimated mean high tide level I-1, W, L),
It is most remarkable near the tidal zone (the average mango surface i-1, ~V, L ~ the average low tide surface, VV, L), followed by the ffσ underwater (the average low tide surface L, 'A7.L). (lower part), z1σ mud (new school).

An example of the average snacking speed of filter steel sheet piles according to a recent survey of the eating speed of harbor steel ('ir7 structures) in public institutions is as follows: 11J, -
The corrosion rate is 0.5 to 1.0/year, and as the depth in seawater increases, the average corrosion rate decreases by p111.
It has been reported that there is a tendency towards rippling, and the rate was less than 0.05 m5/year. In this way, the average corrosion rate of steel sheet piles is
It is particularly noticeable in the 19-shore zone and the tidal zone and the area directly below it (nearly 1.5 m directly below the mean sea level).

For this reason, recently, as a corrosion prevention method for the splash zone and tidal zone where the corrosion rate is the highest, after driving steel sheet piles, the area of the splash zone and tidal zone in the steel sheet pile is
: Corrosion prevention methods such as surrounding the steel sheet pile with a cover (formwork) that matches the shape and filling mortar between the cover and the steel sheet pile are implemented, but construction is carried out by all professionals such as divers. However, the cost becomes high because it is affected by sea conditions such as waves and tide levels. Thus, traditional corrosion protection methods in the splash zone are designed to improve mechanical strength, long-term durability,
It was not an effective anti-commonwealth method in terms of ease of construction and economy.

As a result of intensive research, the inventors found that heavy corrosion-resistant coated steel sheet piles have a high corrosion-proofing effect, durability 1 mechanical properties, and economic efficiency. Continuous coating without 1-5 mzt
It is easy to obtain a desired thickness of h, and the extrusion coating method and the pasting coating method using a pre-fabricated sheet can be applied.
It is possible to control the light of steel sheet piles through a thermoplastic resin phase such as polyethylene, polyethylene pyrene, vinyl acetate, or vinyl chloride, or a heat-adhesive adhesive layer. We discovered that heavy anti-corrosion coated steel sheet piles fully coated with thermosetting resin have superior corrosion resistance, durability and mechanical properties, and are also more economical than conventional corrosion prevention methods. Completed the invention.

Unlike steel pipes, steel sheet piles have joints that fit together during construction, and the heavy corrosion protection coating is inevitably discontinuous at the joints. It is no exaggeration to say that the discontinuity of this heavy corrosion protection coating makes the heavy corrosion protection method for steel sheet piles extremely difficult compared to the heavy corrosion protection method for steel pipes.

In other words, when a heavy anti-corrosion coating is applied to the copper phase, the coefficient of thermal expansion of the synthetic resin is an order of magnitude larger than that of steel, and therefore the coefficient of thermal expansion of the synthetic resin is constantly affected by temperature changes in the filling area where the steel layer with the heavy anti-corrosion coating is used. Internal stress due to thermal expansion and contraction acts within the layer of the heavy corrosion protection coating, and this becomes a factor that reduces the interfacial adhesion between the heavy corrosion protection coating and the steel material. However, in steel pipes that have a continuous heavy anti-corrosion coating on the circumference, the internal stress acts on the entire circumferential surface, and the result is that they cancel each other out as a whole. When heavy corrosion protection coating is discontinuous at joints, such as steel sheet piles, the greatest stress is concentrated at the ends of the heavy corrosion protection coating, which causes the heavy corrosion protection coating to become discontinuous at joints. It acts as a force to peel off from the surface in1. As a result of these forces, if steel sheet piles with heavy anti-corrosion coating are used in a corrosive environment for a long time,
It is well known that the adhesive strength decreases from the edges and gradually progresses to peeling and corrosion.

Therefore, as a result of intensive research, the present inventors found that the tensile modulus of the synthetic resin covering material for steel sheet piles is 0.8 x 10''.
If it is smaller than nL, it will lack rigidity and strength, and will not be able to resist the resistance of the soil when driving steel sheet piles.
j' If the coating material peels off from its ends, and if the tensile modulus exceeds 15 x 101 kg/・,
1 The heavy corrosion protection coating could no longer follow the expansion and contraction of the sheet pile body due to the arA IJL difference of the steel sheet piles, reducing the adhesive strength between the heavy corrosion protection coating and the steel sheet piles, and the tensile modulus of elasticity was 0.8X10-15X. 10. +A%z, synthetic resin 2 For example, if it is coated with a thermosetting resin such as polyethylene (? It has been found that the internal stress caused by this does not inhibit the adhesion between the heavy corrosion protection coating and the steel material, and there is little damage to the coating during pouring.

This invention has a tensile modulus of elasticity of 0.8 x 1 in advance at least in the tidal zone and splash zone of the steel sheet pile installed on the underwater ground.
This invention relates to heavy anti-corrosion coated steel sheet piles in which synthetic resin coated C-shiri sheets of 03 to 15 x 10'ψ are thermally bonded together in close contact with each other via a heat-adhesive adhesive.

This invention will be explained in more detail below with reference to the accompanying drawings.

Figures 1 and 5 show an example of an installed state of R1111t in which J:ll sheet piles according to the present invention are successively driven into the ground and are arranged in a connected manner with steel sheet piles.
They are a perspective view showing an example, and a sectional view showing a partially enlarged cross section of No. 7 Boto paulownia.

FIG. 2 is a perspective view showing an example of a steel sheet pile used in the method of the present invention.

FIG. 6 and FIG. 4 are sectional views each showing an example of the heavy anti-corrosion coated steel sheet pile of the present invention.

The steel sheet pile used in this invention is generally used for civil engineering and construction, and if it has at least a concave surface, a convex surface, a concave surface, a concave surface, a concave surface, a convex surface, etc. The steel sheet pile may have any shape and size.

As shown in Figure 2, a typical sheet pile has a main body with a roughly mouth-shaped cross-sectional structure, with rising parts (sometimes referred to as Franz) 6 on both sides. This is a long steel plate structural member having a joint portion 4 that is bent outward to form a groove with a small inner diameter.

The steel sheet piles 2 are made by sequentially lowering the individual steel sheet piles into the ground, connecting them at the joints 4 of the rising parts on both sides of the steel sheet piles, as shown in Figure 2. As shown in FIG. 1, the blocks 1, which are connected and arranged in a row, are formed. "This": In Una construction, the fifth
As shown in the figure, it is sufficient that at least one side of the protective fence, which is exposed to seawater, river water, etc., is coated with a heavy anti-corrosion coating.

Note that the cross-sectional shape of the 'a+/1 sheet pile does not necessarily have to be as shown in Figure 2; for example, it may be almost straight, Z-shaped, S-shaped, etc. .

The steel sheet pile, which has a main body with a roughly mouth-shaped cross-sectional structure, has a thickness within the range of approximately 5 to 30 vL, and a thickness of approximately 7.5 to
It is made of steel plate with a thickness within 28 mm, and the width is
Approximately 200-800mx, especially 600-600 rrun
, and the height of the rising parts on both sides is about 50 to 3
00 rvn,%m? 70 to 250 mm,
Furthermore, the length may be approximately 2 to 30 m, particularly 5 to 20 m.

Moreover, as the above-mentioned thermoplastic resin, 7j? Re-engineered tylene% Holiglopyreno, copolymer with ethylene tosolobilene, ethylene/vinyl acetate copolymer, etc. (DOL/fin type polymer, polyvinyl chloride, polyester, polyamide, etc.); mixtures thereof , or mixtures of these polymers with thermoplastic resins thereof.

Further, as the thermosetting 441 resin, there is a polyurethane resin.

In addition, the synthetic wood 11'ei' contains known plasticizers, antioxidants, t[(combustion cutters, various coloring agents, fillers (charcoal, silica, sonorac, etc.), etc.). Even if they are combined.

In this invention, the coating layer of the heavily corrosion-protected steel sheet pile is, for example,
The above-mentioned thermoplastic resin, especially; -1-f Cross-link the plastic sheet thoroughly with a strong electron beam to form a cross-linked plastic sheet-1, and then apply the above-mentioned adhesive=n product on the sort while continuously connecting the cross-linked plastic sheets. 1. A laminated sort consisting of an adhesive layer and a cross-linked plastic layer is formed in advance by extruding it into a sheet from a die and laminating it, and then the adhesive layer of the laminated sheet is applied to the surface of the steel sheet pile. It may also be formed by bonding laminated sort.Also, *rjJ's laminated/-t is crosslinked)
(It may be manufactured by heating and bonding with the + agent.

In this invention, the coating layer of heavy anti-corrosion coated steel sheet pile has the total thickness and the thickness of each layer! [, j, but not limited to, the thickness of the cross-linked plastic layer is about 0.1-2
．． 5 M, especially 0.2 to 2.0111 JIL, and the thickness of the adhesive layer is about 0.1 to 2.5 mJ)
t, q'! 0.2 to 2. OB, and the thickness ratio of the crosslinked FLASTINOX layer and the adhesive layer is 1:2 to 2:
The thickness of the entire coating layer is preferably about 0.5 to 5.51 degrees, particularly about 1.7 to 5.0 degrees.

As a method for producing heavy corrosion-resistant coated steel sheet piles of the present invention, for example, first, steel sheet piles are heated at about 60 to 250°C, and further at about 80 to 250°C.
The temperature is within the range of 200°C, and the steel sheet pile is heated to a temperature close to or higher than the bonding temperature of the laminated adhesive layer of -1 to be coated on the steel sheet pile. /
The adhesive layer is placed facing the surface of the steel sheet pile, and the laminated sheet is pressed along the surface of the heated sheet pile by external pressing force, or / Ushita applies heat to the coated notebook from the outside and presses it down with pressure from the outside Pils to make the laminated notebook closely adhere to the surface of the steel sheet pile and bond it, thereby creating a heavy anti-corrosion coating. A method for manufacturing steel sheet piles can be mentioned.

Note that the steel sheet pile used in the above manufacturing method may have its surface subjected to some kind of treatment in advance to improve its resistance to corrosion. ′!
Before using the #l sheet pile in the above-mentioned method, mill scale, red rust, dirt, etc. on the surface of the sheet pile must be removed by sand blasting, sand blasting, (I!2 washing, etc.). This is preferable because it increases the bonding force of the laminated sheet to the steel sheet pile.Also, before applying the laminated sheet, chromium 1 is applied to the surface 1 of the sheet pile.
The adhesion will be even better if you perform surface treatment, rinse treatment, and /-i or epoxy resin Zolimer coating.
Ru.

The heavy corrosion-resistant coated steel sheet pile of this invention is shown in FIG.
As shown in the figure, at least one piece 1 of a steel sheet pile 2 for civil engineering and construction is coated with a cross-linked plastic sheet (layer) 6 with a heat-adhesive adhesive layer 7, which is extremely superior. It has excellent durability and corrosion resistance.

That is, the heavy-duty anti-corrosion coated sheet pile of the present invention has heat resistance, impact resistance, and resistance to harsh natural environments due to the cross-linked plastic layer of the outer layer of the coating layer.

It is durable and can maintain a high-quality protective coating for an extremely long period of time.Also, when the steel sheet pile is driven into the ground to the appropriate size, it makes strong contact with underground stones, gravel, gravel, etc. ζ
In addition, the adhesive layer that exists between the plastic layer and the steel sheet pile is in close contact with the surface of the steel sheet pile and protects it. The surface of the steel sheet pile is directly exposed to water, air, and sunlight.
Since they are not brought into contact with or exposed to cormorant, they can provide a high level of resistance to cormorant eating for a long period of time (for example, about 60 years or more, !14).

4tYi, the heavy anti-corrosion coated steel sheet pile of this invention is extremely excellent in durability, corrosion resistance, and mechanical properties.

Hereinafter, examples of the present invention will be shown.

Examples 1 to 2 [Preparation of A front layer/-1-] Cross-linked polyethylene notebook (glue fraction; 50%, tensile modulus i, 9
Above, thickness; Q, 3+in), thickness approximately 1.2 tru
The adhesive is melt extruded in a bath so that the adhesive layer is
Laminate and laminate No. 1--completely manufactured.

Blend composition of 1-di-1゛'I agent Ethylene/rJ'-olefin co-ilj combination C' [...
I I: 3.2i//10 min, density: 0.88
? /cr&) 17 parts ethylene・[1F, INN
Vinyl copolymer melting point: 5°C, softening point near 8°'Q)
Part 20 Suchin/・Bukunoen・
Styrene block copolymer ('lif1 ship: (ko, 94
'j/c shoulder) 17 parts Coumarone resin (softening point = 96°C) 17 parts chilled phenol copolymer (
Softening point: 100Oc) 2
0 parts hydrogenated rosone ester (softening point: 68°C)
9fSIS The bonding temperature of this adhesive is approximately 160°C.

[Manufacture of heavy anti-corrosion coated steel sheet piles]

After the surface of U-shaped steel Yaya (made by Ippon Steel Co., Ltd.; FSP-I+ type) as shown in Fig. 2 was conditioned by 7-layer blasting, chromic acid-based Zolaimer (Example 1
) After applying the primer coating agent of Ushita or Epogyno resin-based primer (Example 2), the steel sheet piles were heated directly with the flame of a gas burner to -160°C. I kept it.

Next, all the laminated notebooks are pulled out from the roll of rolled laminated notebooks so as to face the surface 1i11 of the added steel sheet pile, and all the laminated notebooks are arranged, and the laminated/sheet piles are Outside 7? Heat the laminated notebook with a flame from a gas burner to make it slightly softer, then roll the central part of the steel sheet pile from the outside of the laminated notebook with a crowned pressure roll of width 1QQam. Then press the laminated sheet f towards both sides of it.
: Deposited on the surface i/+4 of the steel sheet pile, then cooled, bonded, and crosslinked) 0 plastic layer, adhesive layer, and further undercoat paint layer (Example 1: thickness of about 1 tr glue) Heavy-duty anticorrosion-coated steel sheet piles as shown in FIG. 6 were manufactured, each having one layer of romic acid-based primer and one layer of epoxy resin-based primer (Example 2: about 30 tt thick).

[Performance test of the heavy anti-corrosion coated steel sheet pile]

(1) Peel strength For each of the heavy anti-corrosion coated copper arrows manufactured by the above-mentioned manufacturing method, the peel strength (20°C) of the adhesive surface where the laminated notebook layer is joined to the surface of the steel sheet pile is determined by ASTM D.
Measured according to 10 mouths 0 (beer strength measuring method), 20.5 #/' 1 nch (Example 1) and 22. O + g/1 nch (Example 2).

(2) Cold cycle test The tensile modulus of this product manufactured using the manufacturing method described above was 1.9×10
・Heavy-duty anti-corrosion coated steel with polyethylene material of Otori 1/cra%
Af'Z piece 5 Q cm f -40℃X 1 hr
A test was conducted for 100 days under a cooling cycle of ~+60°C x 1 hr, and there was no deterioration or peeling of the coating from the edge of the coating.

(3) Performance test during construction Each of the heavy-duty anti-corrosion coated steel sheet piles manufactured by the above-mentioned manufacturing method was struck at an actual seawall construction site (with a supporting ground N value of approximately 50) with a bipronommer while vibrating at full force. After the heavy corrosion-resistant coated steel sheet piles were installed, they were pulled out and observed to see if the coating layer of the anti-corrosion coated steel sheet piles peeled off or was damaged after such pouring work. During pouring, the coating layer of heavy anti-corrosion coated steel sheet piles peeled off for 11m, and damage (e.g. scratches,
JLF of any of the examples has defects such as scratches etc.
1Y)J There were no occurrences of corrosion-coated steel sheet piles either.

(4) Bending test and torsion test Each of the heavy-duty anti-corrosion coated steel sheet piles manufactured by the above-mentioned manufacturing method was subjected to a bending test and a torsion test to the limit within the 1 Jji strength limit of the steel sheet pile, and the heavy-duty anti-corrosion coated steel sheet piles were We observed whether cracks, etc. occur in the sheet pile coating layer or whether the adhesion of the coating layer decreases, and we found that within the limits of the eave properties of these steel sheet piles under actual use conditions. No abnormalities were observed in bending or twisting of the heavy anti-corrosion coated Ti and Ii sheet piles in any of the Examples.

(5) Drop weight impact test (impact resistance test) For each heavy corrosion-resistant coated steel sheet pile manufactured by the above manufacturing method,
On the surface layer, according to AS T tvIG14,
A hemisphere with a radius of 5/16 inches is suitable for 1.1 5
A short core of A1/-Vt/ was dropped from 2 m, and the condition of the cover layer that received the impact was inspected 11 times. No abnormality appeared in any of the 4ΣΣ steel sheet piles coated with drooping corrosion in the central IW cases.
fJi7 'j'? : 100'/< for each gender
It was more than ycm.

(6) Corrosion Prevention 1 Resilience Each of the corrosion-resistant steel sheet piles manufactured by the above-mentioned production method was immersed for a long time in a saline solution of 1°C≠ at room temperature to remove the heavy corrosion-proofing solution. The situation of peeling of the coating layer of the steel sheet pile and the occurrence of rust on the steel surface were observed respectively. A ' f C Even if it is carried out for 800Q hours, the coating layer will be separated by 11,
No rust occurred on the surface of the steel sheet piles.

Comparative Example 1 The entire surface of a U-shaped steel sheet pile similar to that used in Example 1 (manufactured by Nippon Steel Corporation; FSL-11 type) was prepared by shot blasting, and the undercoat was removed. Manufacture steel sheet piles by directly applying an amine-based coating of tar, evoloxyne, and adhesive to the surface of the steel sheet piles without applying too much coating, and applying an anti-corrosion coating layer (approximately 800 It thick). did. The same performance test as in Example 1 was conducted on the <T1111 sheet pile.

Comparative Example 2 After preparing the surface of a U-shaped steel arrow similar to that used in Example 1 (manufactured by Nippon Steel Corporation; After applying the non-chrysotino 0 limer paint to a thickness of approximately 75 th, the surface of the steel sheet pile is
Epoxy to 1, 'I? A sheet pile having an anti-corrosion coating layer (approximately 250 tt thickness) was coated with riamin-based yarn. The same performance test as in Example 1 was conducted on the steel sheet pile.

The steel sheet piles having the anti-corrosion coating layer of Comparative Examples 1 and 2 were tested in the "performance test during construction" of the same performance test as in Example 1, and the coating layer of the anti-corrosion coated steel sheet pile was Defects such as delamination, damage (e.g. scratches, bruises, etc.) can all occur and cause
In the ``thin impact test (impact resistance test)'', bruises reaching the surface of each preparation occurred, and in the ``anti-poor durability'' part of the broken fish layer had already peeled off after 2,000 hours. #4 on the bottom of the repaired material from the peeled part: l
'+ progressed and large rust was observed.

As is clear from the above implementation examples and comparative examples, the heavy anti-corrosion coated steel sheet pile of the present invention suffers from damage to the coating layer and <
r! ll1ls-c and has a tough coating (one layer acts as a barrier against corrosion, so it can be used for long periods of time)
Corrosion resistance is 1llI JM. Therefore, the service life of the relics (protective fences, etc.) themselves, which are formed from such -1 bow and arrow boards, will be greatly extended, and maintenance costs such as anti-corrosion repairs will be reduced. Moreover, as a factory-manufactured product, it has been subjected to heavy corrosion protection +A& in advance, so a high level of quality control can be ensured, and the period between construction work in a corrosive environment can be significantly shortened, resulting in a total cost reduction.

[Brief explanation of the drawing]

FIGS. 1 and 5 are a perspective view showing an example of a protective fence formed by driving steel sheet piles into the ground, and an enlarged cross-sectional view of a part of the protective fence. (Figure 2 is a perspective view showing an example of the steel sheet pile used in the present invention. Figures 6 and 4 are cross-sectional views showing an example of the anti-corrosion coated steel sheet pile of the present invention. 1 :Protection tilt -2' x+14 sheet piles, 6: Standing.''
2/Flash part, 4: Joint part, 5: Kino layer, 6: Tensile elasticity -to, 5 x 103 to 15 x 103 kV/, synthetic resin month', ., 7: Receptive agent layer.

Claims (1)

[Claims] At least the ebb and flow of the steel sheet piles driven into the underwater ground i)-
And the splash band has a tensile modulus of 0.8 x 103 ~
Synthetic resin of 15X10'/shi 4. A heavy-duty anti-corrosion coated steel sheet pile characterized by being coated with d.