JPH0340920Y2 - - Google Patents

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention relates to a waterproof cover used for corrosion-proofing construction of steel pipe piles for supporting offshore structures on the seabed, for example.

"Conventional technology" In order to protect steel pipe piles installed in ports, etc., the tidal and splash areas of the steel pipe piles are covered with formwork made of FRP covers, etc., and the space between them is filled with mortar, etc., and solidified. The corrosion protection work to be carried out is well known. At this time, the problem is that since cement mortar is injected into water, (a) the injected cement mortar is diluted with water, and the moisture content of the final cement mortar layer is high. Therefore, the expected corrosion resistance and strength cannot be secured.
and (b) components of cement mortar get mixed into the overflowing water and contaminate the surrounding water.

Therefore, in order to deal with this kind of problem, conventionally,
Before pouring cement mortar, drain the water inside the formwork, and make the inside of the formwork watertight or almost watertight by using air pressure, for example, to prevent water from entering the formwork even with this discharge. Methods such as injecting and filling cement mortar while keeping it watertight are applied. However, in this type of construction method that uses pressure air, for example, as in JP-A-55-142810, the upper surface of the formwork is covered with a lid to make the inside of the form airtight, so the joint part of the formwork is It is necessary to seal tightly, which reduces the efficiency of formwork work, and
Problems such as increased costs arise. Also Tokkai Akira
Like the technology of No. 56-135630, the entire formwork is airtight and
By covering with a watertight cover and using this special cover, the inside of the cover becomes a space for air replacement, there is no need to strictly seal the joints of the formwork itself, improving the work efficiency of formwork construction. However, in order to make the inside of the cover watertight or airtight, compressed air must be continuously fed, which requires adjustment of the air pressure inside the cover, which causes problems such as troublesome handling. Furthermore, if mortar or the like leaked from the joints of the formwork, there was a risk that the mortar would flow out into the seawater through the drain hole in the cover. Furthermore, since high air pressure is applied to the inside of the cover, the cover must be made of a strong material, resulting in problems such as an increase in the cost of the cover itself.

Taking these points into consideration, the present applicant has developed a construction method that can reduce costs by facilitating on-site formwork work when placing dry concrete around the outer periphery of steel pipe piles. As a result of intensive research,
By surrounding the formwork with a waterproof cover and using a drainage pump to drain the seawater inside the waterproof cover, there is no need to strictly seal the joints of the formwork itself, making the formwork work more efficient. Do it,
Even if mortar leaks inside the waterproof cover, there is no risk of contaminating the surrounding seawater, and since there is no need to send compressed air into the cover like in the air pressure method, the waterproof cover itself is a low-cost product with just a waterproof function. I came up with the idea that it could be made of objects.

However, at present, such an effective and appropriate waterproof cover has not been provided, and the development of one has been desired.

"Purpose of the invention" The present invention was proposed based on this background, and the purpose is to provide a waterproof cover for use in steel pipe pile corrosion prevention work that is easy to handle and inexpensive.

"Structure of the invention" The invention consists of a belt-shaped waterproof sheet that covers a formwork attached to the outer periphery of a steel pipe pile, a pair of clamps with seals that fix the waterproof sheet to the outer periphery of the steel pipe pile, and a bag-shaped waterproof sheet. It is characterized by being equipped with a waterproof fastener that closes.

"Embodiment" Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 to 6. In the figure, reference numeral 1 is a steel pipe pile, which is constructed so that at least a portion thereof is located below the water surface. Further, reference numeral 2 denotes a formwork provided concentrically at an appropriate distance from the outer periphery of the steel pipe pile, and this formwork 2 is made of, for example, glass fiber reinforced cement (GRC) in the shape of a half-split cylinder. The basic structure is that the panels are butted together and constructed into a cylindrical shape using bolts, nuts, or other binding means. Further, reference numeral 3 denotes a tray for preventing the filling material (mortar, etc.) from flowing out, and is located at the bottom of the formwork 2 and is integrally attached to the outer periphery of the steel pipe pile 1.
Reference numeral 4 indicates a waterproof cover according to the present invention.

As shown in FIGS. 1 and 2, this waterproof cover 4 has a pair of clamps 6, 6 integrally attached to the lower edge of a strip-shaped waterproof sheet 5 that covers the outer periphery of the formwork 1 along the length direction. provided, this clamp 6,6
The basic structure is that it is fixedly attached to the outer periphery of the steel pipe pile 1 by means of the following. The waterproof sheet 5 may be made of synthetic resin such as vinyl, as long as it has a waterproof effect, and the clamps 6, 6 are hinged to each other, and have butt flanges 6a, 6a at their free ends. The structure is such that it can be bundled using a connecting means such as bolts and nuts.
Further, on the inner surfaces of both these clamps 6, 6,
As shown in the figure and Fig. 4, the two-way packing 7,
7 are attached along the length. On the other hand, a pair of holding members 8, 8 for holding the waterproof sheet 5 in a cylindrical shape around the outer periphery of the formwork 2 are integrally attached to the upper edge of the waterproof sheet 5, as shown in FIG. These holding members 8, 8 are hingedly connected to each other, and a plurality of brackets 9 are provided on the outer periphery thereof at equal intervals along the length direction. The waterproof cover 4 is fixed to a scaffold (not shown) by a wire 10 attached to the bracket 9.

Note that waterproof fasteners 11 are attached to both side edges of the waterproof sheet 5 to close the waterproof sheet 5 in a bag-like manner. As shown in FIGS. 5 and 6, the waterproof fastener 11 has a structure in which a fitting groove 12 and a fitting protrusion 13 are fitted by a slider 14 in an uneven manner.

Next, we will explain the case where the waterproof cover 4 configured in this way is used to perform corrosion prevention work on the steel pipe pile 1. As shown in Fig. 2, the waterproof cover 4 is placed at an appropriate distance from the outer surface of the steel pipe pile 1. By placing multiple half-cylindrical panels made of glass fiber reinforced cement (GRC) against each other,
A cylindrical formwork 2 is constructed to surround a steel pipe pile 1, a saucer 3 is connected to the bottom of the formwork 2, and a waterproof cover 4 is attached to surround the formwork 2. The waterproof cover 4 is attached, for example, by the following procedure.

Clamps 6, 6 are attached to the outer periphery of the steel pipe pile 1 to fix the lower end of the waterproof sheet 5.

The upper end of the waterproof sheet 5 is made into a circular shape by holding members 8, 8, and the wire 10 of the bracket 9 is
Secure it to the scaffolding.

The slider 14 of the waterproof fastener 11 is pulled up to close the waterproof sheet 5 like a bag.

After the waterproof cover 4 is attached in this way, the pipe 15 of the drainage pump is inserted into the space between the waterproof cover 4 and the formwork 2 to drain the seawater inside. After confirming that seawater has escaped from the space between the steel pipe pile 1 and the formwork 2, cement mortar is injected into the formwork 2 through the pipe 16 and hardened.

However, in this type of corrosion-proofing construction, cement mortar is filled after the seawater in the formwork 2 is drained, so the mortar layer is not diluted with water, ensuring the desired corrosion-proofing function and strength. Moreover, since the watertight state is maintained by the waterproof cover 4, there is no need to strictly seal the joints of the formwork 2, and formwork work can be carried out efficiently. Moreover, even if mortar leaks from the gaps in the formwork 2, the waterproof cover 4 prevents it from leaking into the seawater, and by sucking up the leaked mortar, contamination of surrounding waters can be reliably prevented. There is also the advantage of being able to

"Effects of the invention" As explained above, according to the invention, it is possible to provide an effective and appropriate waterproof cover for use in corrosion protection construction of steel pipe piles, improve the efficiency of corrosion protection work, and improve quality. It is possible to form a cement mortar layer that can exhibit the desired corrosion prevention and strength improvement effects.

[Brief explanation of the drawing]

Figures 1 to 6 show an embodiment of the present invention, in which Figure 1 is a perspective view showing the state in which the waterproof cover is attached to a steel pipe pile, Figure 2 is a half-sectional view thereof, and Figure 3
4 is a plan view of the waterproof cover, FIG. 5 is a front view of the waterproof fastener, and FIG. 6 is a sectional view taken along the line shown in FIG. 5. 1...Steel pipe pile, 2...Formwork, 3...Saucer, 4
... Waterproof cover, 5 ... Waterproof sheet, 6 ... Clamp, 6a ... Butt flange, 7 ... Packing, 8 ... Holding member, 9 ... Bracket, 1
0...Wire, 11...Waterproof fastener, 1
2... Fitting groove, 13... Fitting protrusion, 14... Slider.

Claims (1)

[Scope of utility model registration request] When pouring a filler such as mortar between a steel pipe pile 1 constructed so that at least a portion thereof is located below the water surface, and a formwork 2 provided around the outer periphery of the steel pipe pile to surround it. A waterproof cover surrounds the formwork 2 and a saucer 3 installed at the bottom thereof, and the waterproof cover 4 includes a strip-shaped waterproof sheet 5 covering the outer periphery of the formwork and a length of the waterproof sheet. A clamp 6 with a pair of seals 7 that is integrally attached to one edge in the width direction and fixes the waterproof sheet to the outer periphery of the steel pipe pile, and a waterproof fastener 11 that closes the waterproof sheet in a bag-like manner. Waterproof cover used.