JP2023072620A - Anti-corrosion structure of steel sheet pile - Google Patents

Abstract

To provide an anti-corrosion structure in which an anti-corrosion cover can be firmly attached even to a steel sheet pile which is highly corroded.SOLUTION: A plurality of steel piles (3) are driven into the sea bottom in front of a steel sheet pile (1), upper parts of the steel piles (3) are fixed to a revetment concrete (5) and a horizontal beam (7) is connected to each steel pile (3), anti-corrosion covers (10) are attached to the horizontal beam (7) and the steel piles (3) with the connecting members (8, 11), and a filler is injected to be solidified between the steel sheet pile (1) and the anti-corrosion cover (10), thus, the entire anti-corrosion structure is prevented from peeling off from the steel sheet pile 1.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to anti-corrosion structures suitable for bank protection structures, particularly steel sheet piles that have been corroded.

To cover a steel sheet pile with an anti-corrosion cover, first, the bottom plate and brackets are welded to the subsea portion of the steel sheet pile, bolt studs and metal fittings are welded to the tidal and splash areas of the steel sheet pile, spacers and reinforcing bars are placed in between, and cranes are placed. It is common to place the FRP anti-corrosion cover on the bottom plate while hanging it, insert each hole of the cover into the bolt stud and fix it with a nut, and fill concrete between the steel sheet pile and the anti-corrosion cover and solidify it. target.
Japanese Utility Model Laid-Open No. 57-137529 Japanese Utility Model Laid-Open No. 60-159061 JP-A-9-177109 JP 2009-215862 A JP 2017-193941 A

However, in the case of corroded steel sheet piles, the wall thickness is reduced and deteriorated, so even if bolt studs and fittings are welded, the bonding force is weak. There was a case where the joint part peeled off from the steel sheet pile due to pressure.
SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an anti-corrosion structure in which a cover can be reliably attached even to steel sheet piles that are highly corroded.

In order to achieve the above object, in the present invention, a plurality of steel piles are driven into the seabed at predetermined intervals in front of steel sheet piles, and the upper portions thereof are fixed to bank protection concrete, and a plurality of horizontal piles are connected to each steel pile. Corrosion protection comprising a beam, a connection member provided in front of the horizontal beam, a corrosion protection cover attached to the horizontal beam via the connection member, and a filler injected and solidified between the corrosion protection cover and the steel sheet pile. structure is adopted.

In the anti-corrosion structure of the present invention, the cover is fixed not to the steel sheet pile but to the separately installed steel pile via the connecting member and the horizontal beam, so the anti-corrosion cover is firmly secured without being affected by the progress of corrosion of the steel sheet pile. can be installed.

1 is a plan view of the anti-corrosion structure according to the present invention, FIGS. 2A and 2B are perspective views of the members used, and FIG. 3 is a longitudinal side view of FIG. 1 showing a state before concrete filling.

A plurality of stud dowels 2 are fixed to the front surface (sea side) of the steel sheet pile 1 of the revetment, and a plurality of steel piles 3 are arranged at intervals on the front surface thereof. Strong H-steel is used. As can be seen from FIG. 3, the steel pile 3 has its lower end driven into the seabed and its upper portion driven into the bank protection concrete 5 above the steel sheet pile by an anchor bolt 4 to be firmly fixed.

A plurality of angle-shaped beam supports 6 (FIG. 3) are provided on the steel pile 3, and a horizontal beam 7 (FIG. 2B) having a U-shaped cross section is mounted and fixed on the beam supports 6. As shown in FIG. Therefore, the steel piles 3 and the horizontal beams 7 form a lattice shape as a whole, forming a stable rigid frame. A plurality of bolt studs 8 are erected on the horizontal beam 7 , and a lattice reinforcing bar 9 for concrete reinforcement is arranged in front of the horizontal beam 7 , and the tip of the bolt stud 8 protrudes from the reinforcing bar 9 .

An anti-corrosion cover 10 made of FRP is installed in front of the reinforcing bar 9, and the cover hole is fitted into the bolt stud 8 and fixed by tightening with an anti-corrosion cap nut 11. - 特許庁The anti-corrosion cover 10 is not of a flat plate but of a strong type in which a plate is joined to a grid board, which has the advantage that the concrete enters the grid portion so that it bites well.

Next, the order of installing the anti-corrosion cover 10 will be described. First, a plurality of H steel piles 3 are driven into the seabed in front of the steel sheet pile 1 and aligned, and the anchor bolts 4 on the top of the piles are fixed to the bank protection concrete 5 to stabilize the steel piles 3. Let Subsequently, a horizontal beam 7 is spanned over the beam support 6 of the steel pile and fixed by welding or the like. Next, the lattice reinforcing bars 9 are placed in front of the horizontal beams 7 and the tips of the bolt studs 8 protrude from the reinforcing bars 9 .

Next, a crane (not shown) is used to install the anti-corrosion cover 10 in front of the reinforcing bar 9 , position the cover hole, fit the bolt stud 8 , and tighten the cap nut 11 . When the lower end of the anti-corrosion cover 10 has a straight shape, the bottom plate 12 is fixed in advance under the steel sheet pile 1 as shown in FIG. do. If there is a gap between the steel pile 3 and the bottom plate 12 or sheet 13, it is sealed with a seal (not shown) as necessary. Depending on the anti-corrosion cover, there is a type in which the lower end is bent to serve as a bottom plate and a type with a seal. Finally, underwater inseparable concrete (not shown) is poured between the steel sheet pile 1 and the anti-corrosion cover 10 and solidified.

Since the concrete is integrated with the stud dowel 2, the steel pile 3, the horizontal beam 7, the lattice reinforcement 9, and the lattice portion of the cover, sufficient strength can be obtained. The bottom plate 12 only needs to position the anti-corrosion cover 10, and the cover is fixed to the steel piles 3 via the horizontal beams 7, so that a large load is not applied to the bottom plate 12, and even if it is attached to the corroded steel sheet pile 1, there is no problem. no. Moreover, since the upper part of the steel pile 3 is fixed to the bank protection concrete 5 with the anchor bolt 4, there is also an effect of preventing the bank protection from collapsing. However, in the case of a bank protection that is not likely to collapse, the steel pile portion protruding above the cover 10 may be removed in consideration of the appearance.

1 is a plan view of a steel sheet pile anti-corrosion structure; FIG. [Fig. 2A] A perspective view of an H steel pile. [FIG. 2B] A perspective view of a horizontal beam. FIG. 2 is a longitudinal side view of FIG. 1;

1 steel sheet pile 3 H steel pile 5 bank protection concrete 7 horizontal beam 8 bolt stud 10 anti-corrosion cover 11 cap nut

Claims (1)

A plurality of steel piles (3) driven into the seabed at predetermined intervals in front of the steel sheet pile (1), the upper portions of which are fixed to the bank protection concrete (5), and a plurality of steel piles (3) connected to the respective steel piles (3). a horizontal beam (7), connecting members (8, 11) provided in front of the horizontal beam (7), and a corrosion protection cover (10) attached to the horizontal beam (7) via this connecting member , a corrosion-resistant cover (10) and a filler injected and solidified between the steel sheet pile (1).

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