JP4827782B2 - Structure of heavy anticorrosion coated steel sheet pile excellent in anticorrosion of joint part and steel sheet pile used for the structure - Google Patents

Description

  The present invention relates to a hat-type steel sheet pile structure that is excellent in anticorrosion properties after placement in a severe corrosive environment such as the ocean, and a steel sheet pile used for the structure.

  Conventionally, steel sheet piles have been widely used as wall structural members such as underground earth retainings, foundation structures and ports in rivers, riverbanks, riverwalls and underground water barriers. Conventionally, U-shaped steel sheet piles have been mainly used as this steel sheet pile, but in recent years it is wider than U-shaped steel sheet piles, and the man-hours required for placing steel sheet piles when forming sheet pile walls Moreover, since the time can be shortened, a hat-type steel sheet pile having a hat-shaped cross section as shown in FIG.

  As a countermeasure when using such a steel sheet pile in a corrosive environment such as a river or the ocean, an anticorrosion method for applying a heavy anticorrosion coating to a tidal zone or a splash zone in contact with the water surface has been adopted. Heavy-duty corrosion-resistant steel sheet piles coated with thick films such as polyethylene and polyurethane can be expected to have durability for several decades. However, generally, heavy-duty corrosion-proof coatings are not applied to the joints of steel sheet piles. For this reason, in the conventional general U-shaped steel sheet pile, for example, as shown in Patent Documents 2 and 3, a steel sheet pile is placed, and then a highly corrosion-resistant cover member is attached to the joint portion by means such as bolts or welding. Anti-corrosion measures to be fixed have been proposed, and even for hat-type steel sheet piles, anti-corrosion measures for joints are desired.

  As shown in FIG. 2, the claw portion 2 for connecting the hat-type steel sheet pile 1 is formed in a shape having a margin in consideration of workability at the time of fitting. As shown in the figure, there is a case in which the connection is shifted to the left and right during fitting, or the connection is curved as shown in FIG. When using a cover member to prevent corrosion of the joint, it is necessary to have a structure that can accommodate the shift even if there is a shift in the connection, and the cover member is attached in seawater. Due to workability problems, the cover member mounting structure must be simple.

JP 2001-131957 A Japanese Patent Laid-Open No. 2000-212985 JP 2004-131957 A

  Therefore, in the present invention, after the hat-type steel sheet pile is constructed, when the joint portion is anticorrosive with the cover member, the cover member can be securely attached even when the joint portion is displaced, and when the cover member is attached. It is an object of the present invention to provide a hat-type steel sheet pile structure having an anticorrosive structure with good workability, and a steel sheet pile used for the structure.

In order to solve the above-mentioned problems, the present invention provides a heavy anticorrosion coating on one surface, and a plurality of steel sheet piles having a hat-shaped cross section, by fitting the claws formed at the ends to each other. The steel sheet pile structure connected by the joint portion to be formed was as follows.
(1) A hook metal fitting is fixed in advance in the vicinity of the claw portion adjacent to the lower side of the bottom of the heavy duty anti-corrosion coating of the steel sheet pile, and has a shape to cover the joint portion, and the surface on the steel sheet pile side is soft. one end portion of the cover member the filler is attached coating of, mounted to engage the hook fitting, by fixing the end portion on the steel sheet pile by fixing means and the other end of the cover member, wherein The joint portion is covered with the cover member, and a filler is interposed between the cover member and the steel sheet pile to fix the cover member.
Further, in the above (1),
(2) is fixed to an end portion on the steel sheet pile by a fixing bracket and the other end of the cover member.
(3) by welding the other end of the cover member is fixed to the upper side of the heavy duty coating on the end of the steel sheet pile.
(4) After fixing the cover member, the cover member and the steel sheet pile were further welded on the upper side of the upper end of the heavy anticorrosion coating and the lower side of the lower end of the heavy anticorrosion coating .
(5) The filler is either semi-cured urethane or epoxy putty.

Moreover, it is used for the steel sheet pile structure as described in (1) above, and the cross-section with the heavy anticorrosion coating on one surface is a hat-shaped steel sheet pile,
(6) A hook fitting for attaching a cover member covering the joint portion is fixed in the vicinity of the claw portion close to the lower side of the bottom of the heavy anticorrosion coating.
(7) Furthermore, in (6), the steel sheet pile is assumed to be provided with a heavy anticorrosion coating to the vicinity of the claw portion.

  According to the present invention, since the end portion of the cover covering the joint portion is fitted to the hook metal fitting, after the hat-type steel sheet pile is constructed, the joint portion is protected against corrosion by the cover member. Even if there is a shift in the portion, the cover member can be securely attached. Further, since the filler is applied to the cover member in advance, the work of filling the filler in the gap between the cover member and the joint portion can be omitted. As a result, a hat-type steel sheet pile structure with enhanced anticorrosion effect of the joint portion can be obtained with good workability, and a steel sheet pile used for the structure can be provided.

Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS.
FIG. 1 shows a steel sheet pile with a hat-shaped cross section, that is, a hat-type steel sheet pile, and in FIGS. 3 and 4, the claws 2 formed at the ends of the hat-type steel sheet pile 1 are fitted to each other and connected. The example which applied this invention to the joint part 7 of a hat-type steel sheet pile structure is shown.

As shown in FIG. 1, a hat-type steel sheet pile 1 includes a central flange portion 3, a web portion 4 extending obliquely from both ends of the flange portion 3, and an arm portion extending laterally from the web portion 4 in parallel with the flange portion 3. 5 and a claw portion 2 formed at an end portion of the arm portion 5.
Each steel sheet pile 1 is provided with a heavy anticorrosion coating 6 on portions corresponding to a tidal zone in contact with the seawater surface or a splash zone where seawater scatters when it is actually placed on site. The heavy-duty anticorrosion coating 6 can be coated on the opposite side of the fitting portion of the claw portion 2 as far as the tip portion as shown in FIG. 1, but the fitting portion is covered. 3, when the adjacent claw portions 2 of the hat-type steel sheet piles are fitted and connected to each other to form a structure like a sheet pile wall, the joint portions 7 of the adjacent steel sheet piles are overlapped. Since a portion where the anti-corrosion coating 6 is not applied is generated, it is necessary to prevent the portion from being corroded.

  Therefore, as shown in FIGS. 3 and 4, a hook metal fitting 8 is welded and fixed in advance near the lower end of the heavy anticorrosion coating 6 and in the vicinity of the claw portion 2 before the hook metal fitting 8 is attached. After the fixed hat-type steel sheet pile is actually placed on site, the lower end portion of the cover member 10 prepared in advance is connected to the engaging portion 9 of the hook metal fitting 8 provided on each adjacent steel sheet pile (FIG. Fit to 5) and attach so as to cover the joint. Thereafter, the upper end portion of the cover member 10 is fixed to the upper end portion of the hat-type steel sheet pile using the fixing bracket 13.

  In that case, the cover member 10 by which the semi-hardened state or the soft filler 11 was previously apply | coated to the surface arrange | positioned at the steel sheet pile side is used. Thereby, the space between the cover member 11 and the steel sheet pile surface can be filled with the filler 11, and the filler 11 is deformed following the shape of the claw portion 2, whereby the filler 11 and the claw portion are in close contact with each other. This improves the performance and prevents seawater and the like from entering the claw portion 2.

Moreover, after fixing the cover member 10, the cover member 10 and the steel sheet pile 1 may be further welded to secure the cover. The welding is preferably performed by forming the beads 14 (FIG. 5) at the four corners of the cover member by arc welding or gas welding, but is not necessarily limited to the four corners.
Generally, since the upper end of the steel sheet pile is embedded in the concrete structure, there is no particular problem if the fixing bracket is left on the upper end of the steel sheet pile, but the upper end of the cover member is welded. In some cases, the fixture 13 can be removed after welding.

  In the above embodiment, although the example which attaches the cover member 10 to the side used as the trough of a steel sheet pile structure was demonstrated, the structure attached to the side used as the mountain opposite to FIG. . However, in general, the example of FIGS. 3 and 4 is more preferable because it is provided at a retracted position.

  In the above embodiment, the hook metal fitting 8 for fixing the lower end portion of the cover member needs to have a certain degree of strength. Therefore, the hook metal fitting 8 is formed of, for example, a steel material and is provided with a coating under the heavy anticorrosion coating 6. It is fixed by welding in advance at a position close to the claw portion 2 at a portion not present. At that time, when the joint portion is formed, the adjacent hooks are positioned so as to be suitable for fixing the lower end of the cover member as shown in FIG.

  And the hook metal fitting 8 is fixed in the direction which the steel sheet pile edge part side opens, The opening part is formed in the magnitude | size which can insert-engage the cover member 10 and the filler 11 between the steel sheet pile surfaces. In order to ensure that the cover member can be attached even if there is a shift in the joint after placement, the hook metal locking portion 9 is formed upward as shown in FIG. It is desirable that the cover member 10 can be smoothly attached to the hook metal fitting 8.

Further, as the fixing bracket 13 for fixing the upper end portion of the cover member 10, a clamp jig in which a fixing means such as a bolt is attached to a U-shaped frame as shown in FIG. 5 can be used. It is also possible to fix the upper end portion of the cover member 10 by using a fixing bracket of a different shape and driving it with a hammer or the like.
In the above-described embodiment, the case where the fixing metal fitting is used for fixing the upper end portion of the cover member 10 has been described. However, the fixing member can be directly welded and fixed without using the fixing metal fitting.

  As described above, in the present invention, since the cover member 10 can be fixed outside the heavy anticorrosion coating 6, a hat-type steel sheet pile with the heavy anticorrosion coating 6 applied to the vicinity of the claw portion as shown in FIG. 1 is used. The entire anticorrosion performance can be further enhanced including the joint portion not covered with the cover member.

The cover member 10 used in the present invention has a flat plate shape, and preferably has a bulge at the center so as not to interfere with the protruding claw portion 2 as shown in FIG. It is advantageous in terms of cost to use a steel material as the material of the cover member, and welding is easy. In this case, it is necessary to provide the anticorrosion coating 12 on the surface as shown in FIG.
As other materials used for the cover member, those formed of a highly corrosion-resistant metal such as stainless steel, fiber reinforced plastic (FRP), or the like can be used. However, in FRP, fixing cannot be ensured by welding.

As the filler previously applied to the cover member, a soft and deformable material such as a semi-cured urethane (semi-cured urethane) or an epoxy putty is used.
By using a cover member that has been pre-coated with such a soft filler, the claw is reliably in contact with the filler, and deterioration due to water permeation of the claw is suppressed as much as possible. Sexual life is greatly increased. Further, it is not necessary to fill the gap between the cover member and the claw portion after the cover member is attached, and the workability can be greatly improved.

  In the present invention, the aspect of the heavy anticorrosion coating is not particularly limited, but generally, heavy anticorrosion of 500 μm or more is performed using a polyolefin or polyurethane resin. At that time, an undercoat layer using epoxy or the like may be provided, and a heavy anticorrosion coating may be applied thereon.

  Although it does not specifically limit also about the steel grade of the steel sheet pile used for this invention, C, Si, Mn and nitrogen, the steel which controlled oxygen, or also Cu, Ni, Cr, Mo, Nb, An alloy steel to which elements such as Ti, Al, Mg, V, and Ca have been added and subjected to shape processing by a hot rolling process is used.

The present invention will be further described below using examples.
Hat-type steel sheet pile (10m in length) with 3mm thick polyurethane heavy-duty anticorrosion coating after rusting the steel surface by blasting on the 3m portion corresponding to the tidal zone, followed by primer treatment, primer coating and polyurethane coating Hook metal fittings were attached by welding as shown in FIGS. 3 and 5 in the vicinity of the claw portion at a position 20 cm below the bottom of the heavy anti-corrosion coating.

After placing these with a bible hammer at a test site on the beach, some joints were 3.5m long and 2mm thick polyurethane anticorrosion coating was applied on both sides except the bottom 20cm and top 30cm. The steel cover member coated with epoxy putty was attached between the hook fittings as shown in FIG. 3, and the upper end thereof was fixed to the upper end portion of the steel sheet pile using a clamp jig. Thereafter, the exposed steel part of the cover and the steel sheet pile were welded. In the remaining joints, the cover member was not attached and the state at the time of placing was kept.
After the construction, 6 months passed and the change in appearance was observed. The joint part to which the cover member as the comparative example is not attached has rusted and has been deteriorated. The examples of the present invention to which other cover members were attached exhibited no very good appearance with no occurrence of rust.

It is a figure which shows the external view of a hat-type steel sheet pile. It is a figure which shows the joint part of a hat-type steel sheet pile. It is a front view of the steel sheet pile structure which provided the cover member which concerns on embodiment of this invention in the joint part of a hat-type steel sheet pile. It is an end view of the steel sheet pile structure shown in FIG. It is a side view of the steel sheet pile structure shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hat-type steel sheet pile 2 Claw part of hat-type steel sheet pile 3 Flange part of hat-type steel sheet pile 4 Web part of hat-type steel sheet pile 5 Arm part of hat-type steel sheet pile 6 Heavy anti-corrosion coating 7 Joint part of hat-type steel sheet pile 8 Hook fitting 9 Hook fitting Engagement part 10 Cover member 11 Filler previously applied to cover member 12 Anticorrosion coating for cover member 13 Fixing bracket 14 Weld bead

Claims (7)

Steel sheet pile structure in which a heavy anticorrosion coating is applied to one surface and a plurality of steel sheet piles having a hat-shaped cross section are connected by joints formed by fitting claws formed at the end portions A hook metal fitting is fixed in advance near the claw portion near the lower side of the bottom of the heavy anticorrosion coating of the steel sheet pile, and has a shape that covers the joint portion, and is a surface on the steel sheet pile side. the one end portion of the cover member filler soft is attached coating, fitted to engage the hook fitting, by fixing the end portion on the steel sheet pile by fixing means and the other end of the cover member The steel sheet pile structure, wherein the joint portion is covered with a cover member, and a filler is interposed between the cover member and the steel sheet pile. Structure of the steel sheet pile according to claim 1, characterized in that fixed to the end portion on the steel sheet pile by a fixing bracket and the other end of the cover member. Structure of the steel sheet pile according to claim 1, characterized in that fixed to the upper side of the heavy duty coating on the end of the steel sheet pile by welding the other end of the cover member. After fixing the said cover member, the cover member and the steel sheet pile were further welded in the upper side of the heavy-duty protection coating upper end and the lower side of the heavy-duty protection coating lower end, The one of Claims 1-3 characterized by the above-mentioned. Steel sheet pile structure.   5. The steel sheet pile structure according to claim 1, wherein the filler is one of semi-cured urethane and epoxy putty. The steel sheet pile structure according to claim 1, wherein a cross-section with a heavy anti-corrosion coating on one surface is a hat-shaped steel sheet pile, and is close to the lower side of the bottom of the heavy anti-corrosion coating of the steel sheet pile A steel sheet pile in which a hook fitting for attaching a cover member covering the joint portion is fixed in the vicinity of the claw portion. Steel sheet piles according to claim 6, wherein the steel sheet pile, characterized in that it is intended to Protective coating is applied to the vicinity of the claw portion.

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