JPS63128092A - Water-proofing work - Google Patents

Abstract

PURPOSE:To perform a water-proofing work with asphalt exhibiting excellent swell-preventing effect without causing environmental pollution, by forming an undercoating layer produced by compounding hydraulic cement powder to an aqueous rubber-asphalt emulsion between a substrate and a water-proofing layer. CONSTITUTION:A water-proofing work is carried out by forming an undercoating layer nontoxic to human body and produced by compounding (A) 100pts.wt. (solid basis) of an emulsion of asphalt and a water-based rubber composed mainly of preferably a (carboxyl-modified) styrene-butadiene copolymer and (B) preferably 30-200pts.wt. of a hydraulic cement between a substrate such as concrete and a water-proofing layer.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention 1] The present invention relates to a waterproofing method for waterproofing a base such as concrete.

[Prior Art] Waterproofing methods include asphalt waterproofing, sheet waterproofing, and paint film waterproofing. When waterproofing a base such as concrete using these construction methods, an undercoat layer is provided on the base to promote adhesion of the waterproof layer to the base and to prevent the waterproof layer from blistering.

There is no perfect primer for preventing blistering, and the only commercially available product is a rubber latex-cement-water mixture (trade name: Tomac Super).

Also, the primers currently used.

There are many types of materials, such as bituminous substances such as asphalt, high molecular weight polymers, etc. dissolved in organic solvents, or emulsions of these materials, and those suitable for the waterproof layer are selected and used.

However, these currently known primers are not satisfactory, and the waterproof layer may peel off from the surface layer of the base after installation due to laitance, flaking, etc., and the surface of the base may not be smooth and uneven. During waterproofing construction, the air trapped in the recesses and cracks in the base expands, and the water that exists between the base and the waterproof layer evaporates, causing the waterproof layer to bulge. This often causes water leakage accidents and poor construction workmanship.

[Problems to be Solved by the Invention] An object of the present invention is to provide a waterproofing method that can solve the conventional problems and sufficiently prevent the blistering phenomenon of the waterproof layer.

[Means for Solving the Problems] The waterproofing method provided by the present invention provides a blistering prevention underlayer comprising a water-based rubber-asphalt emulsion and hydraulic cement powder between the base and the waterproof layer. It is characterized by providing a coating layer.

According to the waterproofing method of the present invention, the water-based rubber-asphalt emulsion is dehydrated by the hydraulic cement powder while the emulsion is broken, and the water is retained internally as crystal water of the hydraulic cement powder, rapidly forming a film without evaporation. do.

Therefore, it can be applied thickly to a waterproof base, removes laitance, lumps, etc., fills recesses, and forms a base with excellent smoothness. This water-based rubber-asphalt emulsion is blended with hydraulic cement powder because it has excellent film strength and adhesion between the base and waterproof layer, and also has the ability to retain water vapor from the base. By providing the undercoat layer, it is possible to prevent the waterproof layer from blistering.

The present invention will be explained in more detail below.

The aqueous rubber-asphalt emulsion used in the present invention may be anionic, cationic, or nonionic, but it must have sufficient emulsion stability to mix with hydraulic cement powder and apply the mixture. There is. The solid content of the rubber and asphalt contained in the emulsion is preferably 50 to 90% by weight. If the solid content is lower than this, it becomes difficult to maintain a sufficient thickness of the undercoat layer that can be applied at one time. If the amount is too high, the viscosity is high and it dries quickly, making it difficult to apply.

Rubbers in the aqueous rubber-asphalt emulsion include natural rubber, styrene-butadiene copolymer, chloroprene polymer, butadiene polymer, inbutylene polymer,
Rubber latexes and resin emulsions such as acrylic acid ester copolymers and ethylene-vinyl acetate copolymers may be used. Among these, when a styrene-butadiene copolymer or a carboxy-modified styrene-butadiene copolymer is used as a main component, a rubber-asphalt solid layer with excellent performance can be formed. Asphalt includes natural asphalt, straight asphalt, blown asphalt, etc., and any of them can be used.

When preparing an aqueous rubber-asphalt emulsion, appropriate amounts of various additives such as emulsifiers and stabilizers are used as necessary to adjust the solid content of the rubber and asphalt. The rubber content in the aqueous rubber-asphalt emulsion is not particularly limited, but is preferably 5 to 50% by weight based on the total solid content of rubber and asphalt.

Hydraulic cement powder used in the present invention includes cement tallinker, ordinary Portland cement, early strength Portland cement, ultra early strength Portland cement, moderate heat Portland cement, jet cement, blast furnace cement, silica cement, fly ash cement, Alumina cement or the like may be used. When mixed with a water-based rubber-asphalt emulsion and the rubber-asphalt emulsion is cured, the hydraulic cement powder must be uniformly dispersed in the water-based rubber-asphalt emulsion and maintain sufficient fluidity during the application of the mixture. The mixture is required to coagulate and form a film as soon as possible after application, and to have high water retention properties after the film is formed. In order to achieve these required performances, it is preferable to use a cement tallinker containing 8% by weight or more of each of Al2O2 and S03 as chemical components, which produces more ettringite products at the end of the hydraulic reaction.

The amount of hydraulic cement powder added is 30 to 2 parts by weight per 100 parts by weight of the solid content of the water-based rubber-asphalt emulsion.
00 parts by weight is preferred. If the proportion of hydraulic cement exceeds the above range, there is a risk of cracking in the formed film, a decrease in low-temperature elongation, etc., resulting in a decrease in performance. If it is less than this range, the coagulation of the rubber-asphalt emulsion will be delayed and free water will be difficult to capture.

Further, if necessary, aggregates, fillers, etc. can be mixed with the aqueous rubber-asphalt emulsion and hydraulic cement powder. As aggregate, sand, crushed sand,
Crushed sand, crushed stone, artificial lightweight aggregate, etc. can be used, and fillers include calcium carbonate, magnesium carbonate, clay, talc, mica, perlite, rubber powder, shirasu balloon,
Fibers etc. can be used. The amount of compounding agents other than the aqueous rubber-asphalt emulsion and hydraulic cement powder used is not particularly limited, but is preferably in the range of 0 to 500 parts by weight per 100 parts by weight of hydraulic cement powder.

When applying the waterproofing method of the present invention to form an undercoat layer, hydraulic cement powder is added to the water-based rubber-asphalt emulsion, and if necessary, compounding agents such as aggregate and filler are added, and the mixture is thoroughly stirred. Stir well with a competent electric stirrer. The viscosity of the mixture thus formed is adjusted with water or a thickener to make it suitable for application. The viscosity of the mixture is preferably in the range of 100 centipoise to io, ooo centivoise, which allows for smoothing of the base and good leveling properties, and thick coating.If the viscosity becomes 100 centipoise and not swirled, the effect of filling the concave portions of the base is poor; It is difficult to uniformly smooth the base surface having uneven portions, and if it exceeds to, ooo centivoise, workability deteriorates, which is not preferable.

The viscosity-adjusted mixture can be applied to the substrate during its pot life with a brush or trowel, or can be applied by spraying with an air gun or airless gun with appropriate pump pressure. The amount of coating should be appropriately selected depending on the condition of the substrate, but it is usually preferably in the range of 0.3 to 8.0 kg/m', and it is possible to apply it evenly so as to completely fill the recesses of the substrate. desirable.

[Effects of the Invention] The present invention has better properties than ordinary primers in removing laitance, lumps, etc. existing in the base, and due to the action of hydraulic cement powder, water evaporation is prevented regardless of whether it is a water-based emulsion or not. , film formation can be performed without removal.

The formed film is reinforced by the action of the hydraulic cement powder, and has excellent film strength and adhesion between the base and waterproof layer, and because of the high water retention capacity of the hydraulic cement, water vapor from the base can also be converted into crystal water. It has absorbent properties and is highly effective in preventing blistering of the waterproof layer.

The waterproofing method of the present invention, which performs waterproofing after treating the base to form a film, is suitable for asphalt waterproofing, sheet waterproofing, and paint film waterproofing, and has an excellent blistering prevention effect especially in asphalt waterproofing. show.

The undercoat material used in the present invention does not pose the risk of fire or other pollution that occurs with conventional organic solvent-based primers, and there is no concern about toxicity to the human body.

Next, the present invention will be explained in more detail with reference to Examples.

Example 1.2, Comparative Example 1 When carrying out waterproofing repair work on the roof of an ALC structure, after completely removing the old waterproof layer, the waterproofing method of the present invention or a method other than the present invention was implemented to replace the undercoat layer. Then, a waterproof layer was provided by applying two layers of synthetic rubber vulcanized sheets. Composition of primer material,
Table 1 shows the type, substrate moisture content, and temperature at the time of construction.

The swelling of the waterproof layer thus obtained was observed. The results are shown in Table 1. Note that crushed sand No. 6 was used as the aggregate (the same applies in the following examples).

Note 1) A: Water-based rubber-asphalt emulsion Made by Nihon Utex Processing ■, water-based emulsion of styrene-butadiene-straight asphalt, solid content concentration 55
%, solid content rubber approximately 25% by weight remaining straight asphalt 2) B: Hydraulic cement powder made by Nihon Utex processing■, hydraulic cement powder (AJLzO3 approximately 11.4% by weight)
, S03 approx. 10.2% by weight) 3) Rubber latex/cement paste: JSR) Max-Bar/Cement/Water = 115/2 weight ratio blend JSR) Max-Bar made of Nikkaku Utex processing ■, mixed with cement Styrene-butadiene latex, solid content 45% Example 3.4, Comparative Example 2 When carrying out waterproofing repair work on the roof of an RC structure,
After the old waterproof layer was completely removed, a waterproofing method according to the present invention or a method other than the present invention was applied to provide a primer layer and then a waterproof layer using a hot asphalt waterproof insulation method. Table 2 shows the composition and type of the undercoating material, the amount of moisture in the base material, and the temperature at the time of construction. The undercoat formulation used in Example 3.4 and the undercoat material in Comparative Example 2 were the same as in Examples 11 and 2 and Comparative Example 1, respectively.

The swelling condition of the waterproof layer thus obtained was observed. The results are shown in Table 2.

Examples 5-8. Comparative Example 3 When carrying out waterproofing work on the roof of a newly built RC structure, a waterproofing method of the present invention or a method other than the present invention was implemented to provide an undercoat layer and then a waterproof layer using a hot asphalt waterproofing contact method.

Table 3 shows the composition and type of the undercoating material, the moisture content of the base material, and the temperature at the time of construction. The undercoat formulation used in Examples 5 to 8 was the same as in Example 1. Furthermore, as the undercoat formulation and asphalt primer used in Comparative Example 3, an asphalt emulsion with a solid content of 30% was used.

The swelling condition of the waterproof layer thus obtained was observed. The results are shown in Table 3.

Examples 9 to 12, Comparative Example 4 When carrying out waterproofing work on the roof of a newly built RC structure,
An uninvented waterproofing method or a waterproofing method outside the present invention was carried out to provide an undercoat layer and then a waterproof layer by a hot asphalt waterproof insulation method. Table 4 shows the composition and type of the undercoating material, the amount of moisture in the base material, and the temperature at the time of construction. The undercoat formulations used in Examples 9 to 12 and the undercoat material in Comparative Example 4 were the same as in Examples 1 and 2 and Comparative Example 1, respectively.

The swelling condition of the waterproof layer thus obtained was observed. The results are shown in Table 4.

Claims (1)

[Claims] (1) A waterproofing method characterized by providing a blistering-preventing undercoat layer made of a water-based rubber-asphalt emulsion and hydraulic cement powder between the base and the waterproof layer.