JPS6145029A - Anticorrosive sealing work for coupler of heavily corrosion-resistant steel tubular sheet pile - Google Patents

Abstract

PURPOSE:To obtain complete seal for the couplers of a steel pipe sheet pile by a simple method in which a water-expansible sealant is coated on the periphery or inner surface of any one of the couplers of heavily corrosion-resistant steel pipe sheet piles, the couplers are joined with each other, and the sheet piles are driven into the bottom under water. CONSTITUTION:The periphery of a steel pipe pile 14 is covered with a heavily anticorrosive coat 13 to for, a heavily corrosion-resistant steel pipe sheet pile 1 which has T-shaped coupler 5 and L-shaped couplers 6. A water-expandible sealant 2 is the sprayed or coated on the couplers 5 or couplers 6 and a part of the coat 13. The sheet piles 3 with the sealant are driven into the ground of a river or seabed after joining of the couplers 5 and 6, where the sealant 2 is expanded in several days after construction to seal up the spaces of the couplers. The coupler portions of the steel pipe sheet piles can thus be simply sealed up.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention provides a heavy anti-corrosion coating for the joints of the heavy-duty anti-corrosion steel pipe sheet piles when driving the heavy-duty anti-corrosion steel pipe sheet piles into the underwater ground to construct water-stop walls, etc. The present invention relates to a corrosion-proof sealing method for the joints of heavy-duty corrosion-proof steel pipe sheet piles, which can protect the joints and completely seal the joints to prevent river water or seawater from entering.

[Prior art]

Steel pipe sheet piles are mainly used for civil engineering work on rivers and seawall construction at ports, and are required to have strength as piles or members and water-tightness at joints.

Conventionally, joint structures for steel pipe sheet piles include (1) a C-C type joint structure in which tubular joints 4 with slits are interlocked with each other as shown in FIG. 9, and (2) a C-C joint structure as shown in FIG. 1, there is a C-T type joint structure in which a slitted tubular joint 4 and a T-shaped joint 5 are engaged with each other, and (b) a pair of L-shaped joint 6 and a T-shaped joint as shown in FIG. An L-T type joint structure in which 5 and 5 are interlocked with each other is known.

Among these joint structures, joint structures (1) and (2) are often used when water-stopping properties are particularly required, and water-stopping properties are achieved by filling the voids in the joint with a water-stopping material such as mortar or concrete. is ensured. In addition, in port revetment construction, emphasis is placed on steel pipes and their mutual connection strength rather than water-stopping properties, and less emphasis is placed on the completeness of the water-stopping properties of joints (6).
) joint structure is often used.

However, there is no particular problem when steel pipe sheet piles are used for constructing temporary structures such as coffered steel pipe sheet pile walls, but when steel pipe sheet piles are used for constructing harbor revetment walls as mentioned above, steel pipe sheet piles are It becomes a permanent strength member. Therefore, the durability of the structure is greatly influenced by the corrosion resistance of the steel pipe sheet pile.

To explain the water-stopping method of the conventional C-T joint structure, as shown in Figs. 8 and inserted into the joint cavity, and the curable water stop material 7 is filled into the joint cavity.

In addition, if the methods shown in FIGS. 12 and 16 cannot be adopted, as shown in FIG. The material 7 is injected and filled into the joint cavity.

On the other hand, when steel pipe sheet piles for temporary cofferdam walls are to be removed after being used for a certain period of time in civil engineering work in rivers or under the sea, for example, caisson etc. are constructed within a cylindrical temporary cofferdam wall using steel pipe sheet piles. If the steel pipe sheet piles are removed after construction, the corrosion resistance of the steel pipe sheet piles will not cause any problems, but long-term durability is required for steel pipe sheet piles used for quays, revetments, etc. in rivers and ports. be done.

For this reason, there is an urgent need to develop a new heavy-duty corrosion-resistant steel pipe sheet pile that has better corrosion resistance than conventional steel pipe sheet piles and has economical advantages over conventional corrosion protection methods such as cathodic protection. Against this background, heavy corrosion-resistant steel pipe sheet piles coated with a urethane elastomer heavy-duty anti-corrosion coating have recently been developed.

This heavy-duty anticorrosive coating is formed by urethane elastomer coating using a spray method, and can form a thick coating even on complex-shaped joints in steel pipe sheet piles.

However, even in such heavy corrosion-resistant steel pipe sheet piles, the corrosion resistance of the joint itself cannot be said to be perfect due to the following points.

(1) There is a risk that the coating painted on the inner and outer surfaces of the joint may peel off due to mutual rubbing between the joints during driving.

(2) If it is difficult to make the joint watertight, or if complete watertightness cannot be achieved as with conventional joints, the joint will corrode from within.

In particular, in the case of heavy corrosion-resistant steel pipe sheet piles constituting the L-T type joint structure shown in FIG. Since it is difficult to secure a sufficiently large gap in the joint, it is impossible to fill it with a water stop material such as mortar, and as a result, almost the entire surface of the joint is submerged in water, which poses a problem in terms of corrosion resistance.

To solve this problem, it is necessary to prevent damage to the heavy anti-corrosion coating of steel pipes and the heavy anti-corrosion coating of joints when driving steel pipe sheet piles,
It is necessary to ensure complete watertightness of the joint after driving.

[Purpose and structure of the invention]

The purpose of this invention is to provide a corrosion-proof sealing method for joints of heavy-duty corrosion-resistant steel pipe sheet piles that can advantageously solve the above-mentioned problems. Alternatively, a water-expandable elastic sealing material 2 is applied near the joint to form a heavy-duty anti-corrosion steel pipe sheet pile with a sealing material, and the joints of a large number of heavy-duty anti-corrosion steel pipe sheet piles with a sealing material are interlocked with each other and driven into the underwater ground. The present invention provides a corrosion-proof sealing method for a joint portion of heavy-duty corrosion-proof steel pipe sheet piles, which is characterized in that the water-expandable elastic sealing material 2 is then expanded by reaction with water to fill the joint gap.

〔Example〕

Next, the present invention will be explained in detail with reference to illustrated examples. Figures 1 to 6 show a first embodiment of the present invention. 14, both sides of the web of the T-shaped joint 5, and the outer surface of the pair of L-shaped joints B, a heavy-duty anti-corrosion coating 16 of urethane elastomer or polyethylene is integrally applied to form the heavy-duty anti-corrosion steel pipe sheet pile 1. The water-expandable elastic sealing material 2 is spray-coated or applied over the entire T-shaped joint 5 in the heavy-duty anti-corrosion steel pipe sheet pile 1 and the outer surface of the heavy-duty anti-corrosion coating 16 located slightly away from the joint 5. The heavy-duty anti-corrosion steel pipe sheet pile 3 with a sealant is formed by being integrally adhered by injection coating, and then the joints 5 and 6 of the heavy-duty anti-corrosion steel pipe sheet pile O with a large number of knoll materials are interlocked with each other as shown in Fig. 2. In this state, each sheet pile is sequentially driven into the bed of a river or sea.

The joint gap is filled with water, and as shown in FIG. 3, adjacent heavy corrosion-resistant steel pipe sheet piles 1 are connected in a completely watertight state.

4 to 6 show a second embodiment of the present invention, and as shown in FIG. 4, a pair of L-shaped joints in a heavy corrosion-resistant steel pipe sheet pile 1 configured as described above A band-shaped water-expandable elastic sealing material 2A is attached and fixed to the inner surface of the flange of B with an adhesive, and a water-expandable elastic sealing material 2B having a cross-sectional shape of an angular shape is attached to the outer surface of the distal end side and the distal end surface of the flange of the above-mentioned angular joint 6. is pasted and fixed with adhesive, and a band-shaped water-expandable elastic sealing material 2C is pasted and fixed with adhesive on the outer surface of the steel pipe 14 between the pair of L-shaped joints 6, and the heavy corrosion-resistant steel pipe sheet pile 6 with the sealing material is formed. The joints 5 and 6 of a large number of heavy-duty anti-corrosion steel pipe sheet piles with sealing materials are then interlocked with each other as shown in Figure 5, and each sheet pile is sequentially driven into the bedrock of a river or sea. .

A few days after installation, water-expandable elastic sealing materials 2A and 2B.

When 2C expands by 1.5 to 10 times due to reaction with river water or seawater and fills the joint gap, as shown in Figure 6, the adjacent heavy corrosion-resistant steel pipe sheet piles are completely sealed. Connected with clean water.

The present invention can also be applied to a corrosion-resistant 7-rule of a C-C type joint structure or a C-T type joint structure of heavy corrosion-resistant steel pipe sheet piles.

Next, the water-expandable elastic sealing material will be explained. This sealing material is specially modified rubber, and when it comes in contact with water, it expands in volume and creates water expansion pressure.The sole has a function of filling gaps and exhibiting a water-stopping effect through a complete sealing action. It is a material. Specially modified rubber has a hydrophilic part, which forms hydrogen bonds with water molecules, resulting in physical and chemical water absorption.
Hydration occurs, and as a result, self-volume expansion occurs, and the volumetric expansion rate can be increased by approximately 1.5 to 10 times by appropriately selecting the type and properties of the expansion material contained in the rubber. It will be done.

Next, Figure 7 shows the relationship between the number of days immersed in water and the volumetric expansion coefficient of commercially available water-expandable elastic sealing materials (MC-2005, KC-2005, manufactured by Asahi Denka Kogyo). FIG. 8 shows the relationship between and the expansion pressure.

Note that the commercially available water-expandable elastic sealing material has sufficient strength against wear.

[Effects of the Invention] According to the present invention, the water-expandable elastic sealing material 2 is applied to the joints or the vicinity of the joints of the heavy-duty corrosion-resistant steel pipe sheet pile 1 to form the heavy-duty corrosion-resistant steel pipe sheet pile 6 with a sealing material. The joints of heavy-duty anti-corrosion steel pipe sheet piles 3 are interlocked with each other and cast into the underwater ground, and then the water-expandable elastic sealing material 2 is expanded by reaction with water to fill the joint gap. It is possible to completely seal the joints of the anti-corrosion steel pipe sheet piles 1, to reliably prevent water from entering the joints, and to prevent corrosion inside the joints. When the joints are engaged with each other and driven into the underwater ground, the joints, which are hard materials, do not come into contact with the heavy-duty anti-corrosion coating 16, and the water-expandable elastic sealing material 2, which is a soft material applied to the joints, provides heavy-duty anti-corrosion protection. Since it comes into contact with the coating film 1, it is possible to obtain effects such as being able to prevent the heavy corrosion protection coating film 16 from being cut and damaged during driving.

[Brief explanation of the drawing]

1 to 6 show a first embodiment of the present invention, in which FIG. 1 is a cross-sectional plan view of a heavy-duty anti-corrosion steel pipe sheet pile with a sealant, and FIG. FIG. 6 is a cross-sectional plan view showing the state in which the joints are engaged with each other, and FIG. 6 is a cross-sectional plan view showing the anti-corrosion seal portion of the completed joint portion. 4 to 6 show a second embodiment of the present invention, in which FIG. 4 is a cross-sectional plan view of a heavy-duty anti-corrosion steel pipe sheet pile with a sealant, and FIG. 6th cross-sectional plan view showing a state in which the joints of
The figure is a cross-sectional plan view showing the anti-corrosion seal portion of the completed joint. FIG. 7 is a diagram showing the relationship between the number of days immersed in water and the volumetric expansion coefficient of the water-expandable elastic sealing material, and FIG. 8 is a diagram showing the relationship between the number of days immersed in water and the expansion pressure of the water-expandable elastic sealing material. Figures 9 to 11 are cross-sectional plan views showing conventional joint structures for steel pipe sheet piles, Figures 12 and 16 show conventional joint sealing methods, and Figure 12 shows the use of water-stopping material. FIG. 16 is a perspective view showing a state in which the water stop material is inserted into the joint gap; FIG.
FIG. 4 is a perspective view showing a state in which a water stop material is injected into a joint gap, and FIG. 15 is a cross-sectional plan view showing a joint portion of a conventional heavy corrosion-resistant steel pipe sheet pile. In the figure, 1 is a heavy corrosion-resistant steel pipe sheet pile, 2 is a water-expandable elastic sealing material, 2A is a band-shaped water-expandable elastic sealant, 2B is a water-expandable elastic sealant with a cross-sectional shape, and 2C is a band-shaped water-expandable elastic sealant. 3 is a heavy corrosion-resistant steel pipe sheet pile with a sealing material, 5 is a T-shaped joint, 6 is an L-shaped joint, and 13 is a heavy corrosion-resistant coating film. To the ward i Iisun ward etsu ＼↑ Kuniba) School district (〕 School＼T

Claims (1)

[Claims] A water-expandable elastic sealing material 2 is applied to the joints or the vicinity of the joints of heavy-duty corrosion-resistant steel pipe sheet piles 1 to form a heavy-duty corrosion-resistant steel pipe sheet pile 3 with a sealant, and the joints of a large number of heavy-duty corrosion-proof steel pipe sheet piles 3 with sealing materials are interlocked. A method for corrosion-proofing sealing of joints of heavy-duty anti-corrosion steel pipe sheet piles, characterized in that the sealing material is poured into the ground at the bottom of the water, and then the water-expandable elastic sealing material 2 is expanded by reaction with water to fill the joint gap.