JPH029638B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel sheet waterproofing method for civil engineering and construction using a mixture of water-based rubber-asphalt emulsion and hydraulic cement.

BACKGROUND ART Conventionally, the so-called hot asphalt method, in which asphalt felt or asphalt fings are laminated using heated and melted asphalt, has been the most popular waterproofing method for civil engineering and construction. The thermal asphalt construction method has many years of experience in construction and can form a reliable waterproof layer, but on the other hand, there is a risk of fire outbreaks due to heating and melting of the asphalt, environmental pollution due to the generation of odors, occupational safety of workers due to high-temperature work, and Due to the need for skill in construction timing, there has been a demand for a waterproofing method that can be easily performed at room temperature. The typical room-temperature waterproofing methods are the sheet waterproofing method and the paint film waterproofing method.
In both cases, the waterproof layer is thin and it is difficult to make multiple layers, so they are inferior to the thermal asphalt waterproofing method in terms of waterproofing reliability.

In the current sheet waterproofing method, the thickness of the waterproof sheet layer is as thin as 0.8 to 2.0 mm, so the surface precision of the base has a large effect on the durability of the waterproof layer. If the base is not smooth, the permeability of the primer will be uneven, and the amount of adhesive applied will also be uneven, which will reduce the effectiveness of the waterproof sheet's overall adhesion to the base, and cause the waterproof sheet to peel or blister. This weakens the waterproof performance and causes water leakage accidents. Furthermore, if there are any irregularities or protrusions on the base, even if they are small, there is a risk that the waterproof sheet will be locally stretched, accelerating ozone deterioration and ultraviolet deterioration. In general, stress concentration tends to occur in the cutout areas, so there is a risk that the waterproof sheet will be damaged by protrusions or depressions in the base and break from those areas.If the waterproof base is concrete or mortar, It must be finished sufficiently smooth by direct finishing with a metal trowel, and if there are any unevenness, it must be sanded, and concave areas should be smoothed using polymer cement, etc., and the unevenness of the base will make it waterproof. It must be ensured that the sheet does not break.

When pasting insulation material on top of a tarpaulin sheet, organic solvent-based adhesives cannot be used depending on the insulation material, and after pasting the insulation material, water from rain will not get between the insulation material and the tarpaulin sheet. It's difficult to do so. In the case of sheet waterproofing, organic solvent-based adhesives are often used as adhesives, so it is necessary to dry the adhesive properly, and there are also health and safety problems due to organic solvents, so it is difficult to use indoors or underground. It cannot be used in places where there is a risk of insufficient ventilation, such as in structures. Water-soluble resin emulsions, epoxy resins, urethane resins, etc. are available as adhesives to improve this drawback, but since water-soluble resin emulsions require drying, their adhesive strength is weak in humid areas, and epoxy resins The elongation rate is low in the urethane resin type, and the urethane resin type has difficulty in water-resistant adhesive strength, and both are expensive.

Furthermore, since the adhesives currently used for tarpaulin sheets have poor waterproof performance, even slight peeling when the tarpaulin breaks, at the ends of the tarpaulin sheets, or at the joints of tarpaulin sheets can lead to water leakage. There is a risk.

The present invention aims to improve the above-mentioned drawbacks, and uses a mixture of water-based rubber-asphalt emulsion and hydraulic cement powder as an unevenness adjustment material (surface treatment) material, an adhesive, and a waterproofing material in a sheet waterproofing method. By pasting the water-based rubber-asphalt emulsion, the hydraulic cement powder destroys the emulsion and undergoes chemical and physical dehydration, rapidly forming a film without evaporation, and causing the rubber-asphalt emulsion to The emulsion-forming film is reinforced by the action of hydraulic cement powder, improving the film strength and adhesion between the base and waterproof sheet, and also has the performance as a waterproofing material, resulting in more reliable sheet waterproofing. We have discovered what can be done and arrived at the present invention.

That is, the method of the present invention provides a sheet waterproofing method in which a waterproof sheet is attached to a waterproof base using a mixture of water-based rubber-asphalt emulsion and hydraulic cement powder.

The present invention will be explained in detail below.

The water-based rubber-asphalt emulsion used in the present invention may be anionic, cationic, or nonionic, but it is suitable for mixing with hydraulic cement powder and applying the mixture to attach a waterproof sheet. It is necessary to have sufficient emulsion stability. The solid content of the rubber-asphalt emulsion contained in the emulsion is 50% by weight.
It is preferable that it is above. If the solids content is lower than this, the rubber can be coated in one go. It is not possible to maintain a sufficient thickness of the asphalt forming layer, and the ratio of hydraulic cement powder required to dehydrate and harden the rubber-asphalt emulsion in a short period of time increases, making the formed film brittle. , watertightness cannot be maintained.

Rubbers in asphalt include natural rubber, styrene-butadiene copolymer rubber, butyl rubber, polybutadiene rubber, chloroprene rubber, acrylic rubber, ethylene-vinyl acetate copolymer, and styrene-butadiene copolymer rubber or carboxy-modified styrene. It is preferable to use a rubber-asphalt solid layer containing a -butadiene copolymer as the main component since it is excellent in terms of performance and economy.

The asphalt in the rubber-asphalt includes natural asphalt, straight asphalt, blown asphalt, and the like, any of which can be used. When preparing an aqueous rubber-asphalt emulsion, an emulsifier and a stabilizer are used, and the total solid content of rubber and asphalt is adjusted to 50% by weight or more in the emulsion. The rubber content in the rubber-asphalt is not particularly limited, but is most preferably 5 to 50% by weight based on the total solid content of the rubber-asphalt.

Hydraulic cement powders used in the present invention include cement clinkers that produce more ettringite products at the end of the hydraulic reaction, ordinary Portland cement, early strength Portland cement, ultra early strength Portland cement, moderate heat Portland cement. Preferable examples include jet cement, blast furnace cement, silica cement, fly ash cement, and alumina cement. The hydraulic cement powder is mixed with the water-based rubber-asphalt emulsion, and when the rubber-asphalt emulsion is cured, it must be uniformly dispersed in the water-based rubber-asphalt emulsion, and the mixture must be applied during the coating and pasting process. The ability to maintain fluidity and to solidify this mixture as quickly as possible after pasting the tarpaulin sheet is required. In order to achieve these required performances, it is necessary to use a hydraulic cement powder that has strong water hardness and is adjusted so that it does not set immediately after being dispersed in water, such as a powder that produces more ettringite products at the end of the hydraulic reaction. A cement clinker containing 10% by weight or more of each of Al ₂ O ₃ and SO ₃ as chemical components is preferable.

Waterproof sheets used in the present invention include vulcanized rubber sheets, non-vulcanized rubber sheets, vinyl chloride sheets, ethylene resin sheets, and rubberized asphalt sheets, any of which may be used. Insulating materials used include polyethylene foam, polystyrene foam, urethane foam, and vinyl chloride foam.When selecting these insulating materials, consider the heat insulating properties, moisture permeation resistance, processing method, dimensions, stability, etc. It is necessary to select one with appropriate specifications from the following points.

When carrying out the method of the present invention, a primer such as polymer dispersion or asphalt emulsion is first applied to the substrate depending on the condition of the substrate. Add hydraulic cement powder to the water-based rubber-asphalt emulsion and stir well using an electric stirrer with sufficient stirring capacity. The mixing ratio of the water-based rubber-asphalt emulsion and the hydraulic cement powder is important and is determined by both the curability and the hardened film. The mixing ratio of rubber-asphalt solids and hydraulic cement powder in the aqueous rubber-asphalt emulsion is 1:2 to 1:1 by weight.
0.3 is appropriate. If the proportion of hydraulic cement is too much than the above range, there is a risk of cracks in the formed film and a decrease in low-temperature elongation, resulting in a decrease in adhesive strength and waterproof performance. Furthermore, if the proportion of hydraulic cement is too low than the above range, the rubber-asphalt emulsion will set slowly and free water will not be easily removed.

Furthermore, aggregates, fillers, etc. can be mixed as necessary. Silica sand, crushed stone, gravel, etc. can be used as aggregates, and calcium carbonate, clay, talc, mica, perlite, rubber powder, shirasu balloons, fibers, etc. can be mixed as fillers. The viscosity of the mixture of water-based rubber-asphalt emulsion and hydraulic cement powder is adjusted with water or a thickener to make it suitable for coating. The ratio of water to cement in the mixture is also an important factor; the water/cement ratio must not exceed 1.5; too much water will delay hardening and leave free water behind. Therefore, the solid concentration in the aqueous rubber-asphalt emulsion must be selected from this point as well. A mixture of water-based rubber-asphalt emulsion and hydraulic cement powder is applied to the base in the pot life using a brush, sponge, trowel, etc., and a waterproof sheet is attached at the same time. Seams between tarpaulin sheets are overlapped to improve waterproof performance. In addition, when pasting insulation material on top of the waterproof sheet as required, after the mixture of water-based rubber-asphalt emulsion and hydraulic cement powder has hardened, apply the mixture of water-based rubber-asphalt emulsion and hydraulic cement powder. Coat it on top of the waterproof sheet and attach the insulation material. Even when attaching two layers of waterproof sheets, the above mixture is similarly applied on top of the first layer of waterproof sheets, and the second layer of waterproof sheets is attached. After pasting the waterproof sheet, it is usually preferable to provide a protective layer such as applying a top coat or pouring mortar.

The waterproof layer formed by the sheet waterproofing method of the present invention has a rubber-modified asphalt layer, so that it can provide waterproof reliability comparable to that of a hot asphalt waterproof layer. Also, unlike the hot asphalt construction method, it is a room-temperature construction method and does not use solvents, so it is superior in work safety and fire hazard prevention.

The waterproofing method of the present invention can be used in civil engineering, new construction waterproofing of architectural structures, repair of various types of exposed waterproofing, repair of iron plate roofs, indoor underground waterproofing, moisture proofing of structures, formation of airtight layers, etc.

Next, examples of the present invention will be given.

Example 1 A roofing with asphalt waterproofing sand was applied to a roof made of concrete with a deck plate structure, and this deteriorated and leaking water was repaired and waterproofing was performed on the waterproofing base. Defects in the old waterproofing and asphalt layers were removed and repaired with cement mortar containing JSR Tomak Super (a styrene-butadiene copolymer latex manufactured by Japan Synthetic Rubber Co., Ltd.), and the base was cleaned. Apply an asphalt cation emulsion as a primer at a rate of approximately 0.2 kg/ ^m2 ,
Let dry for about 30 minutes. JSR is a styrene-butadiene copolymer modified asphalt emulsion with a concentration of 85% (contains approximately 26% copolymer in total solids).
Add 10 parts by weight of a 30% aqueous solution of Emulgen E910 (polyoxyethylene nonyl phenyl ether, manufactured by Kao Atlas Co., Ltd.) to 100 parts by weight of Hullcoat (manufactured by Japan Synthetic Rubber Co., Ltd.) to stabilize the total solid content to 70%. Adjusted to. With respect to 100 parts by weight of this rubber-asphalt emulsion, 17% by weight of Al ₂ O ₃ as a chemical component,
60 parts by weight of cement clinker containing 22% by weight of SO ₃ were added and stirred with an electric stirrer until homogeneous.

Immediately pour this mixture onto the repair base and spread it with a sponge brush to a coating thickness of approximately 2.5 kg/m ^2. At the same time, spread out the rolled up PVC sheet (Ronproof, manufactured by Ronseal Industries Co., Ltd.) and apply it. Ivy. After curing for 1 day, finish paint (EVA emulsion paint, JSR Hartup, Japan Synthetic Rubber)
Co., Ltd.) and completed the waterproofing work.

Approximately six months after construction, no abnormalities such as blisters, wrinkles, or peeling were observed in the waterproof layer, and water leakage had completely disappeared.

Separately, a waterproof layer was formed on a pavement board according to the same specifications, and the performance was measured after curing for one week. The peel adhesion strength with the substrate was 20Kg/25mm width, and the adhesion performance test (according to JIS A6008) passed, and the above mixture was 2.5
The water permeability of the unit coated with Kg/m ² (according to JIS A1404, water pressure 3 Kg/m ² ) was 0.

Example 2 Newly built underground structure with RC structure concrete finish,
We carried out waterproofing work on the basement exterior walls. After cleaning the wet waterproof base, asphalt cation emulsion was applied as a primer at a rate of 0.1 kg/m ² and allowed to dry. JSR Hull Coat was stabilized in the same manner as in Example 1, and the total solid content was adjusted to 60%. Add 50 parts by weight of alumina cement (manufactured by Nippon Cement Co., Ltd.) powder to 100 parts by weight of the rubber-asphalt emulsion, mix with an electric mixer until uniform, add a thickener, and stir further to make the mixture. It thickened. Immediately apply this mixture to the waterproof base using a sponge brush.
1.3 mm thick vulcanized rubber sheet (nitroof ^,
Made by Nitto Denko Co., Ltd.) was spread and pasted to complete the waterproofing work.

One week after construction, no abnormalities such as floating, wrinkling, or peeling were observed, and after placing protective mortar for the waterproof layer, the site was backfilled. After backfilling, there was no water leakage inside the underground wall, and the waterproofness was good.

A waterproof layer was formed on a damp pavement board using the same specifications, and the performance was measured after curing for one week at a temperature of 20°C and a humidity of 100%. Peel adhesion strength with base is 5
Kg/25mm width.

Example 3 A newly built roof with an RC structure and mortar finish was waterproofed. After cleaning the waterproof base, use as a primer.
Approximately 0.1 kg/10 times diluted solution of JSR Tomatsu Super
m ² coated and dried. As in Example 1, JSR
50 parts by weight of cement clinker having the same composition as in Example 1 and 50 parts by weight of silica sand No. 6 as aggregate to 100 parts by weight of rubber-asphalt emulsion in which Hull Coat was stabilized and the total solid content was adjusted to 60%. A pre-mixed powder was added and mixed using an electric stirrer until uniform. Immediately pour this mixture onto a waterproof base and spread it with a sponge brush to a ratio of 2.0 kg/ ^m2 .
Co., Ltd.) was spread out and pasted. Approximately 4 hours after pasting, the same mixture used for laminating the rubber surface sheet was spread on the rubber surface sheet at a ratio of 1.5 kg/ ^m2 , and polyethylene foam (Toray Pef, Toray Industries, Inc.) was applied as a heat insulating material. (manufactured by) were attached. One day later, in the same manner, pour a mixture of rubber-asphalt emulsion, hydraulic cement, and aggregate in the same proportions as above onto the insulation material, and use a sponge brush to mix the mixture to approximately 1.5 kg/ ^m2 . While spreading it, I stuck the rolled up rubber ass sheet. After curing for one day, finishing paint JSR Harttsup was applied and the insulation and waterproofing work was completed.

Approximately 6 months after construction, there are blisters, flakes, wrinkles,
No abnormalities such as peeling were observed, and the waterproof property was good.

Comparative Example 1 In Example 2, after applying a primer for a vulcanized sheet and drying, a water-soluble resin emulsion type adhesive for a vulcanized sheet was applied at a rate of 1 kg/m ² and dried properly. Afterwards, the rolled up vulcanized rubber sheet was spread out and pasted. Paste 3
After curing for a day, the vulcanized rubber sheet developed flakes and wrinkles, and was in a peeling state. When the floating, wrinkled, and peeled parts were cut out, it was found that the inside contained moisture, and the adhesive for the vulcanized sheet had been re-emulsified. A waterproof layer was formed using damp pavement boards with the same specifications, and the performance was measured after curing for one week at a temperature of 20°C and 100% humidity. The peel adhesion strength with the substrate is
The weight was 0.5Kg/25mm width, and the peeling state was peeling at the interface with the waterproof base.

Claims (1)

[Claims] 1. A sheet waterproofing method in which a waterproof sheet is attached to a waterproof base using a mixture of water-based rubber-asphalt emulsion and hydraulic cement powder. 2 The mixing ratio of water-based rubber-asphalt emulsion (solid content) and hydraulic cement powder is 1:2 ~
The sheet waterproofing method according to claim 1, wherein the water (including water in the emulsion)/hydraulic cement ratio is 1:0.3 and does not exceed 1.5.