JPS6015779B2 - Corrosion-resistant cover structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the structure of a corrosion-resistant cover that does not require hanging brackets for supporting formwork when constructing a pier or the like, ie, allows the use of ordinary brackets.

Normally, when constructing a pier, multiple steel pipe piles are driven into the seabed to form the pillars, each steel pipe is connected with steel to create a formwork, and this is filled with concrete to complete the pier. However, since steel pipes are subject to corrosion mainly due to ebb and flow and splashing, it is common practice today to apply a corrosion-resistant cover to the steel pipes. However, as can be seen from FIG. 1, when the steel pipe 1 is covered with the cover 2, the bracket 3 supporting the formwork cannot be directly welded to the steel pipe 1. For this reason, a hanging reinforcing bar 4 is unavoidably provided on the bracket 3, and the upper end of the reinforcing bar is welded to the steel pipe 1. 5
, 6 is H steel for formwork.

Since the brackets are removed once the concrete work is completed, if the brackets are of the hanging type, the cost will be higher by the amount of hanging reinforcing bars. Moreover, the amount of work required for construction increases accordingly. It would be possible to complete the concrete work before corrosion occurs on the steel pipes and then apply a corrosion-proof cover, but this type of work usually takes a long time, so it cannot be used at present.

If a hole is drilled perpendicularly to the bracket of the corrosion-resistant cover, the cover will be damaged, and if a cover with holes is used, the filler inside will leak out. The corrosion-resistant cover of the present invention was created in view of these circumstances, and although it has a hole at the mounting position of the bracket, it is constructed so that it will not leak even if a filler is injected into the hole.

Specifically, a window-shaped hole is formed in the corrosion-resistant cover, and the entire hole frame is bent inward. After the corrosion-resistant cover is placed over the steel pipe, a metal frame is inserted into each hole, the metal frame is welded to the steel pipe, and the metal frame and the inner edge of the hole are joined via packing. After completing the concrete work and cutting out the brackets, the holes are filled with filler and covered with corrosion-resistant lids. Embodiments of the present invention having such characteristics will be described in detail below with reference to the accompanying drawings.
FIG. 2 shows the corrosion-resistant cover 2 of the present invention in a state covered with the steel pipe 1, and the cover 2 has a rectangular hole 7 elongated in the vertical direction.

(In addition, Figure 2 is shown in a position rotated 90 degrees from Figure 1.) In this figure, the holes are provided in two locations, upper and lower, but the shape, size, and number of holes can be determined as necessary. . square hole 7
is similarly formed on the opposite side of the cover 2. Since Fig. 2 shows the state after construction is completed, the square hole 7 is covered with a lid 8. Figure 3 is an enlarged sectional view taken along line m-m in Figure 2.
The mounting position of the bracket 3 is shown with an imaginary line.

Each end of the cover 2 is bent inward to form a square hole 7. Portions 2a and 2M corresponding to the frame of square hole 7 and cover 2
It is desirable that the thickness be greater than that of the wall to provide strength.
Further, a metal frame 9 as shown in FIG. 5 is fitted with iron into the inner surface of the square hole 7, and the inside of the metal frame 9 is welded to the steel pipe 1. It is more convenient to manufacture each side of the metal frame 9 in advance and join the four corners on site. Also, the holes 11 in the metal frame are made oblong or round holes to facilitate bolt tightening. After the metal frame 9 is fixed to the steel pipe 1, it is then joined to the bent portion 2b of the cover with the packing 10 interposed therebetween. Use bag type bolts and nuts, or F/R after tightening.
・Coating with P or the like is effective in preventing corrosion.
The upper and lower surfaces of the square hole 7 are also exactly the same as shown in FIG.
Since the square hole 7 has such a structure, even if the filler 12 is injected into the corrosion-resistant cover 2, there is no chance of it leaking out.

Since the surface of the steel pipe 1 is exposed in the square hole 7, the bracket 3 can be easily welded when assembling the formwork.
When the construction is completed, the bracket 3 is removed, a filler is filled into the square hole 7, and the square hole 7 is covered with a lid 8 made of F.R.P. In this case, a highly viscous epoxy filler is used, and a packing 10 is also interposed between the corrosion-resistant cover 2 and the lid 8. As described above, according to the corrosion-resistant cover of the present invention, the bracket can be welded to the steel pipe without any problem, making the construction easier and reducing the cost.

[Brief explanation of the drawing]

Fig. 1 is a side view showing a conventional hanging bracket, Fig. 2 is a front view showing a corrosion-resistant cover of the present invention, and Figs. 3 and 4 are enlargements taken along lines mm and W-W in Fig. 2. The sectional view and FIG. 5 are perspective views of the metal frame. 1... Steel pipe, 2... Corrosion-proof cover, 2a
...Thick wall part, 2b... Thick wall bent part, 3... Plaquet, 7... Square hole, 8... Lid, 9...
...Gold frame, 10...Packing, 12...
···filler. Fig. 1 Chicken 2 Fig. Hoko 3 Fig. 4 Fig. 5 Fig. 5

Claims (1)

[Claims] 1. A hole is formed in a portion of the corrosion-resistant cover corresponding to the bracket welding position of the steel pipe, the edge of the hole is bent inward, a metal frame is fitted into the hole, and the inside of the metal frame is is fixed to the steel pipe, and the inner edge of the hole and the metal frame are joined through packing. 2. Claim 1, wherein the hole is a vertically elongated square hole.
Corrosion-resistant cover structure 3 according to claim 2. The corrosion-resistant cover structure according to claim 2, wherein the wall thickness of the portion constituting the hole is larger than the wall thickness of the cover.