JPS59206553A - Waterproof method of concrete and mortar structure - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a waterproofing method for concrete and mortar structures.
The present invention relates to a method of achieving complete waterproofing by applying a coating composition containing glass flakes as an essential component.

The rooftops and flat roofs of large reinforced concrete or mortar buildings such as factories, warehouses, gymnasiums, and various city buildings are
As a result of exposure to natural phenomena such as direct sunlight, wind and rain, and harsh conditions such as expansion and contraction due to ground subsidence and vibrations, cracks and fissures occur within a short period of time, causing rainwater to leak. This will greatly shorten the lifespan of these buildings.

Traditionally, in order to prevent such water leakage accidents, asphalt was poured over the entire surface of rooftops and flat roofs in several steps.
Furthermore, it is common practice to apply curing mortar on top of this, or apply the so-called "asphalt waterproofing method."
This method is not perfect, and not only does it require a large amount of man-hours to install, but the asphalt has poor weather resistance and ages in a relatively short period of time. The problem was that major construction work had to be carried out that involved removing the entire mortar layer and then repairing it.

As a method to overcome this difficulty, there is a so-called "sheet waterproofing method" in which a synthetic resin sheet is adhered to the entire construction surface, and it has been put into practical use. Due to insufficient adhesion around parapets or at joints between floors and walls, water leaks from these areas are unavoidable, and when repairing these leaks, water vapor may be trapped. This method cannot be called a perfect method as it tends to cause "blisters" and requires a great deal of effort to remove them.

In order to solve these problems, in recent years, a waterproof primer is first applied to the construction surface, then a glass cloth is laid on top of it, and an intermediate coating mainly composed of synthetic resin such as urethane rubber is applied as an upper layer. A so-called "resin waterproofing method" that applies a topcoat or other coating agent has been developed and put into practical use. This method has the advantage of covering corners, seams, drain areas, etc. where complete adhesion cannot be expected in sheet waterproofing, and is a modern method that can achieve almost complete waterproofing. During construction, in order to ensure complete adhesion between the glass cloth and the primer surface, and to prevent air bubbles from getting caught in the glass cloth and remaining in the intermediate and top coat layers, skilled, careful and extensive work is always required. This method is still not perfect as it requires a large amount of labor.

As a result of intensive research into the current situation, the present inventors found that
We have discovered that by applying a coating composition containing glass flakes as an essential component and epoxy resin as a main spreading agent, it is possible to provide a waterproof coating for an ultra-thick film, and have thus arrived at the present invention. did.

That is, the present invention provides a coating composition for the surface of concrete and mortar structures, which contains glass flakes as an essential component and further contains an epoxy resin containing a hardening agent, or an epoxy resin spreading agent containing a hardening agent and bituminous material. This is a method of waterproofing concrete and mortar structures, which is characterized by applying .

The present invention will be explained in detail below.

The glass flakes, which are an essential component of the coating composition used in the present invention, are scaly glass flakes with a thickness of 01 to 10 microns and a maximum length of 30 to 30 microns, and are coated with a hardening agent. When a coating composition obtained by blending an epoxy resin containing epoxy resin or a spreading agent containing bituminous material into a spreading agent is applied to a concrete or mortar structure, glass flakes are present in the coating layer. As a result of the layered arrangement, the curing shrinkage stress that occurs during the curing process of this coating layer is alleviated, and even if the glass cloth installation process is omitted,
It is possible to form an ultra-thick film of 5 mm or more without residual internal stress, and it also exhibits strong adhesion to the substrate, producing a waterproofing effect equal to or greater than that of laying glass cloth. (He will join the army.

In addition, the glass flakes arranged in layers within the coating layer not only have the effect of significantly retarding the rate of permeation of external substances such as moisture, ions, and oxygen into the substrate, but also
Even when distortion or expansion/contraction force is applied to the coating layer due to ground subsidence or earthquakes, it absorbs these and prevents cracks and
It has the effect of preventing the occurrence of "cracks", and as a synergistic effect, it has a waterproof effect that lasts for an extremely long period of time.

In order to maximize the stress relaxation effect and permeable substance blocking effect of glass flakes, the size and maximum length)5
Particular preference is given to using glass flakes from 0 to 800 microns.

The spreading agent of the coating composition used in the present invention is an epoxy resin containing a curing agent or a bituminous substance, and this combination is selected for the following reasons.

In other words, epoxy resin is cured by a curing agent during use, or is a two-component bonding material consisting of a main resin and a curing agent, and forms a strong polymer film through a chemical reaction between the main resin and the curing agent. The degree of shrinkage that occurs during this curing process is extremely small compared to other synthetic resin binders.
This low shrinkage, combined with the shrinkage stress relaxation effect of the glass flakes, minimizes the degree of shrinkage of the waterproof coating layer after waterproofing construction, thereby maximizing the adhesion to the substrate. This is because it can be done.

Furthermore, the reason why bituminous material is added is that although bituminous material is a very cheap substance, it has extremely good water resistance, so it can impart even more excellent water resistance to the coating composition used in the present invention. By selecting and using an appropriate bituminous material depending on the target species from among various bituminous materials with different softening points, flexibility and pliability can be imparted to the coating composition used in the present invention, and as a result, , vibrations, ground subsidence, temperature, etc., the waterproof properties of the coating composition used in the present invention are further enhanced.

Examples of the epoxy resin used in the present invention include bisphenol Am epoxy resins, bisphenol F type epoxy resins, and polyfunctional epoxy resins having an epoxy equivalent of 150 to 1,000. Bisphenol A type or bisphenol F type epoxy resins in the range of .

Next, as a curing agent used for curing the above-mentioned epoxy resin, 7 is generally used for curing epoxy resin.
Min7 ducts, polyamide resins, polyamines, modified polyamines, etc. are selected and used depending on the purpose, but especially aliphatic polyamines, aromatic polyamines, and complex polyamines used as solvent-free curing agents. Cyclic polyamines and the like are most suitable for achieving the objectives of the present invention.

The bituminous materials used in the present invention include coal cool, coal tar pitch ψ petroleum tar, petroleum pinochia asphalt, petroleum asphalt is particularly suitable for achieving the objectives of

In addition, the coating composition used in the present invention further includes pigments such as extender pigments and coloring pigments Y, additives such as thickeners and silane coupling agents, and toluene-xylene, methyl ethyl ketone, methyl in butyl ketone, etc. Solvents such as butyl alcohol and inpropyl alcohol are used as necessary.

The coating composition used in the present invention is prepared by adding pigments and, if necessary, solvents to an epoxy resin or a mixture of an epoxy resin and a bituminous substance, and then dispersing the mixture using a p-luminizer, sand grinder, attritor, etc. A method of waterproofing the surfaces of concrete and mortar structures using the coating composition of the present invention is carried out as follows.

+1+ Prior to repair work, wet sandblasting or sanding the construction site to completely remove any deposits on the construction site, washing with water, and drying completely, then apply an epoxy resin waterproof primer if necessary. The purpose of applying this epoxy resin-based waterproof primer is to improve the adhesion between concrete or mortar and the coating composition used in the present invention. Main component is bisphenol A type or bisphenol F, W epoxy resin, amine adduct, polyamide resin,
Depending on the purpose, the primer is selected from commercially available epoxy resin-based waterproof primers containing polyamine-modified polyamine as a curing agent and, if necessary, pigments, solvents, additives, etc.

(2) Next, the coating composition used in the present invention is applied to the entire surface of the construction site. The coating method may be spray coating, brush coating, roller coating, etc., but in order to achieve a multilayered arrangement of the main component glass flakes and to obtain an ultra-thick film of 5 or more fins, it is necessary to The most effective and efficient method is to pour the coating composition used in the present invention onto the area and then level the surface uniformly using a spatula or trowel.

(3) After the coating composition has dried, if necessary, the coating composition used in the present invention is applied again to uniformly finish the whole. Although this step is not an essential condition for bringing out the effects of the present invention, it is extremely effective because it can correct paint loss and pinholes that occur during the previous step construction, so that the maximum waterproofing effect can be obtained.

As described above, complete waterproofing of concrete and mortar structures can be achieved by performing only 2 to 3 construction steps. In addition to omitting the process of installing water, the structure will not cause any water leakage accidents such as rain leakage for many years.

Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples.

Examples 1 to 6 (1) Preparation of coating composition Among the base ingredients of Examples 1 to 6 whose formulations are shown in Table 1, the components excluding the glass flakes and the silane coupling agent were mixed and kneaded, and then the attritor was mixed and kneaded. After kneading and grinding using a DeSilver stirrer,
Add glass flakes and a silane coupling agent to make it homogeneous, add the curing agent from Example 1 and mix at °C,
A coating composition for use in the present invention was obtained.

(2) Making the waterproof covering board After sanding, washing and drying, size 20 x 20
Nira Sun Flake Guard Primer (trade name, epoxy resin waterproof primer, manufactured by NOF ■) was applied with a brush to a dry film thickness of 30 microns on the X2Gl mortar board, and the primer was dried.

Next, the coating compositions of Examples 1 to 6 were dried using a spatula onto the same mortar plates as those used in Examples 1 to 3 and Comparative Examples 1 to 6 so that the dry film thickness was 5 mm per coat. Apply il+ M-coat primer (trade name, epoxy waterproof primer, manufactured by M-COL Products) so that the film thickness is 5 fins, lay down e+ glass cloth, and (3) apply M-coat intermediate coat (trade name, urethane resin type). Waterproofing of Examples 1 to 6 of the present invention and comparative examples obtained by applying M-coat top coat (trade name, Rankan resin waterproofing agent, manufactured by M-Fool Products) Regarding the cover plate, we conducted the following acceleration tests to check the workability during waterproofing construction.
The performance of the waterproofing method was evaluated.

(1+ Water absorption measurement test plate at 45°a, zoochi R,) 1. The water absorption rate of the waterproof coating layer was measured by gravimetric method.

(2) Wet test The test plate was exposed to 45'0, 100% R, H for 24 consecutive months.

(3) Vibration humidity test Attach the test plate to a constant temperature and humidity tester with vibration (Tabai Seisakusho M), 40°C, 190cm R, H, excitation force 5oKf,
It was exposed for 24 consecutive months under the condition of frequency i o 00 Hz.

(4) Accelerated weather resistance test The test plate was attached to a due cycle weather meter tester (manufactured by Suga Test Instruments), and the black panel temperature was 63°Q.
10 continuous cycles under 18 minutes of rainfall during one cycle (120 minutes)
．． 000 hours exposure.

The test results for each item above are shown in Table 2.

As is clear from Table 2, based on the waterproofing method of the present invention,
In Examples 1 to 6, the number of man-hours required for waterproofing construction was drastically reduced compared to the comparative example, and not only did they exhibit extremely excellent workability, but also in terms of performance, they exhibited extremely low water absorption rates, and Even in accelerated tests under harsh conditions, this method showed extremely promising results, exceeding those of the "resin waterproofing method," making it particularly useful industrially.

Claims (1)

[Claims] Applying to the surface of concrete and mortar structures a coating composition containing glass flakes as an essential component and a spreading agent such as an epoxy resin containing a hardening agent or an epoxy resin containing a hardening agent and bituminous material. A method for waterproofing concrete and mortar structures.