JP2000178944A - Impervious structure for dam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the deterioration of concrete by building with a simple work and prevent water leakage from cracks by spraying primer and an ultra- high speed hardening impervious membrane to the surface of the upstream side of a dam body and further coating a protective film on the surface of the impervious membrane. SOLUTION: For a primer 3, a resin capable of securing adhesion between concrete and impervious membrane 4 is used, and polyurethane resin is used for the impervious membrane 4. In this case, the impervious membrane 4 is used for the protection against ultraviolet rays and rain water as well as the improvement of appearance, and further a protective film 5 having an excellent weather resistance is formed. For the protective film 5, one liquid type water base paint using acrylic resin or a two liquid type isocyanate hardening type paint using acrylic urethane-based resin is used. Because of this, the impervious membrane 4 of continuous polyurethane resin having a uniform thickness can be formed even to outside angle or inside angle or other angle portions such as recessed portion or level difference portion. In this way, an impervious structure can be built in a short period of time by spray coating an ultra-high speed hardening impervious membrane.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dam structure for dams.

[0002]

2. Description of the Related Art As shown in FIG. 5, a water impervious structure of a dam in a gravity type concrete dam or an arch type dam is provided with a water impervious plate 13 and a seam drainage hole 15 in a vertical seam.
As shown in FIG. 6, the seepage control structure of the fill dam has a seepage control sheet 17 attached to the upstream side surface of the embankment body 16.

[0003]

However, water-blocking structures such as gravity-type concrete dams and arch-type dams are intended to block only vertical joints. No leak prevention measures were taken. In addition, the construction of the seepage control structure of the fill dam was a large-scale operation, and not only was it troublesome to attach the seepage control sheet at the corners and joints, but also technically difficult.

[0004] The present invention has been made in view of such a problem, and an object of the present invention is to be able to construct by a simple operation, prevent deterioration of concrete, and prevent water leakage from a cracked portion. It is to provide a dam impermeable structure that can be prevented.

[0005]

In order to solve the above-mentioned problems, a dam impermeable structure is provided in which a primer is applied to an upstream side surface of a dam embankment, and a super-hardening impermeable film is formed on the primer. It is characterized by being spray-coated, and a protective film is spray-coated on the upper surface of the water barrier film.

[0006] By forming a super fast-setting and seamless water-blocking film by spraying on the upstream side of the dam body, a water-blocking structure can be constructed by a simple operation. Since the water barrier film covers the entire upstream side surface of the embankment, the concrete can be prevented from deteriorating. Further, since the water-impermeable film has a predetermined elasticity and a predetermined expansion / contraction, it can cope with cracks in concrete. In addition, the use of the ultra-fast curing polyurethane resin liquid can improve the workability and workability when constructing the water-blocking structure.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. (1) in FIG. 1 is a cross-sectional view of a water-blocking structure of a gravity concrete dam, and (2) in the same figure.
Is a cross-sectional view of a water impermeable film, and FIG. 2 is a schematic view of a coating apparatus.

FIG. 1 shows a water-blocking structure 1 of a gravity type concrete dam. The water-blocking structure 1 has a primer 3 applied to the upstream side of a dam body 2 of the dam and a high pressure spray applied onto the primer 3. And a protective film 5 spray-coated on the upper surface of the water-blocking film 4.

The primer 3 may be any one of a one-pack type and a two-pack type as long as it is a solvent type and a non-solvent type as long as it has a property of ensuring the adhesion between the concrete and the water barrier film 4. It is possible. More specifically, a urethane-based one-pack moisture-curable type Sun PC-F (registered trademark: manufactured by Mitsui Chemicals, Inc.),
Solvent two-pack type Sun PC-U (registered trademark: manufactured by Mitsui Chemicals, Inc.) based on urethane-modified epoxy resin, or solventless NK flake (registered trademark) based on epoxy resin mixed with special filler : Nippon C.R.M.) can be used.

The polyurethane resin of the water barrier film 4 uses a urethane main agent mainly composed of an organic isocyanate and a urethane curing agent obtained by adding a curing catalyst, a coloring agent or a filler to a main component of polyol and / or polyamine. I do.

The above-mentioned urethane main agent has an isocyanate group (N) at the terminal obtained by reacting an organic isocyanate represented by diphenylmethane diisocyanate (MDI) with a polyol such as a polyoxyalkylene polyol.
(CO group).

As the urethane curing agent, a mixture of the polyol and / or polyamine such as aromatic diamine and polyoxyalkylene polyamine with an organic metal catalyst and a coloring agent is used.

In the present embodiment, the polyurethane resin has a pot life of a few seconds and a touch dry time of 3 to 60.
Second, rubber elasticity development time is 1 to 10 minutes, elongation is 250
An ultra-rapid urethane spraying material of 600%, for example, Rim Spray F-1000 (registered trademark: manufactured by Mitsui Chemicals, Inc.) is used. This is, as shown in Table 1 below, the pot life is a few seconds,
8 to 20 seconds for touch dry time, 2 to 2 hours for rubber elasticity
It has physical properties of elongation of 350 to 410% for 3 minutes.

[Table 1]

In order to protect the water barrier film 4 from ultraviolet rays, rainwater and the like and to improve the appearance, a protective film 5 having excellent weather resistance is formed. As the protective film 5, a one-pack type aqueous paint based on an acrylic resin, an SBR resin, a urethane-based resin, or a two-pack type isocyanate cured based on an acrylic urethane-based resin or a fluorine-containing urethane-based resin is used. Use a type of solvent-based paint.

The water barrier film 4 is formed by spray coating at a high pressure by a coating device 6 as shown in FIG. This spraying can be performed from the lower part to the upper part of the upstream side surface of the embankment body, from the upper part to the lower part, or from the center part to the end part. Furthermore, it is also possible to first spray-coat from the corners or the corners where the work is difficult. In addition, the water-impervious film 4 is configured such that a urethane base agent and a urethane curing agent filled in a container are sent from a drum pump 7 to a high-pressure metering pump 8 and pressurized to 80 to 120 kg / cm ^2, and a heater of a spray device is provided. Heat is applied to the spray gun 9 to collide with the spray gun 10 to form a mist (mist), which is sprayed and applied to the surface to be sprayed.

FIG. 3 shows a water-blocking structure 11 of an arch dam, which is formed on the upstream side surface of the bank 2 in the same manner as described above. FIG. 4 shows a water shielding structure 12 of the fill dam, which also has the same configuration as described above.

[0017]

According to the present invention, it is possible to prevent the deterioration of concrete and the leakage of water from cracks, and to form a water barrier film by a simple operation.

A water barrier film made of a polyurethane resin having a uniform thickness and a seamless shape can be formed even at a corner portion of a concave portion, a step, or the like, an inward corner or an outward corner where work is difficult.

Since a seamless water blocking film can be formed on the entire upstream side surface of the embankment, the water blocking can be improved.

By spraying and forming an ultra-fast-curing water barrier film, a water barrier structure can be constructed in a short time.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a water-blocking structure of a gravity concrete dam, and FIG. 1 (2) is a cross-sectional view of a water-blocking film.

FIG. 2 is a schematic view of a coating apparatus.

FIG. 3 is a cross-sectional view of a water-blocking structure of an arch dam.

FIG. 4 is a cross-sectional view of a water shielding structure of a fill dam.

FIG. 5 is a perspective view of a waterproof structure in a conventional gravity concrete dam.

FIG. 6 is a perspective view of a water blocking structure in a conventional fill dam.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Water-blocking structure 2 Embankment body 3 Primer 4 Water-blocking film 5 Protective film 6 Coating device 7 Drum pump 8 Metering pump 9 Heater 10 Spray gun

 ──────────────────────────────────────────────────続 き Continuing from the front page (71) Applicant 390001993 Mitsui Fudosan Construction Co., Ltd. 3-2-5 Kasumigaseki, Chiyoda-ku, Tokyo (72) Inventor Takashi Goto 2-31-1, Nihonbashihamacho, Chuo-ku, Tokyo Mitsui Fudosan F term (reference) in Construction Co., Ltd. 4H017 AA04 AB03 AC04 AD06 AE03

Claims (2)

[Claims] 1. An upstream side surface of a dam body is coated with a primer, a super-hardening water barrier film is sprayed over the primer, and a protective film is sprayed on the upper surface of the water barrier film. The dam impervious structure characterized by that. 2. The dam impermeable structure according to claim 1, wherein the impermeable film is made of polyurethane resin.