Waterproofing repair methods and waterproofing repair structures

Abstract

To provide a waterproof repair method and waterproof repair structure that uses a wet-type substrate preparation material and mechanical fastening method without any inconveniences. [Solution] A waterproof repair method is obtained in which a new waterproof layer of vulcanized rubber sheet is laid and fixed on the upper surface of the existing waterproof layer via a dry-type leveling sheet, by a waterproof repair method comprising the steps of laying and fixing a dry-type leveling sheet on the upper surface of the dry-type leveling sheet, and then laying and fixing a vulcanized rubber sheet on the upper surface of the existing waterproof layer.

Description

Technical Field

[0001] The present invention relates to a waterproof repair method and a waterproof repair structure using a dry-type base adjustment material. More specifically, it is suitable for a roof waterproof repair method of a building, and relates to a covering-type waterproof repair method and a waterproof repair structure in which a vulcanized rubber-based sheet is used as a new waterproof material from above without removing the existing waterproof material.

Background Art

[0002] Generally, in the covering-type waterproof repair method, when the compatibility and combination of the existing and new waterproof materials are poor, a wet-type base adjustment material such as a liquid or paste type is often used, or an interlayer primer is used to improve the compatibility of both.

[0003] The types and construction structures of waterproof materials used in building structures are diverse. Usually, there is no problem as long as the waterproof material has performance equivalent to or better than the service life of the building. However, there is no such material with current technology. Before rebuilding a building, the function of the waterproof material is often impaired and it is often replaced with a new waterproof material. Replacement means removing the old waterproof material once and installing a new waterproof material. This new waterproof material is selected to have waterproof performance equivalent to or better than the removed waterproof material. This is called the removal-type waterproof repair method.

[0004] However, removing a deteriorated waterproofing material and installing a new one would disrupt daily life and business operations during that time. Furthermore, the removal of waterproofing materials incurs significant time, labor, and costs. Therefore, in recent years, as described in "A Guide to Rooftop Renewal Using Sheet Waterproofing, published by the Synthetic Polymer Roofing Association" (Non-Patent Literature 1), a technology has emerged that allows for the installation of new waterproofing materials without replacing the existing ones. This technology allows for the installation of new waterproofing materials over existing ones without removing them, even if the waterproofing material has deteriorated or developed partial defects. This is called the overlay waterproofing repair method. Because this overlay waterproofing repair method does not involve removing the existing waterproofing material, it generates less waste compared to the removal method, which involves replacing the existing waterproofing material. This results in shorter construction periods and cost savings, leading to its widespread adoption. However, this overlay waterproofing repair method is not without its drawbacks. In principle, the old and new waterproofing materials must be made of the same material and constructed using the same method. If the same material is used, the waterproofing materials will be compatible with each other, and the same performance can be guaranteed as a substitute. Currently, with advancements in waterproofing technology and intensifying cost competition in the construction industry, users are increasingly demanding high-performance waterproofing materials and shorter replacement intervals (construction periods). This trend is accelerating, and there is a growing trend towards mechanical fastening methods that disregard the compatibility between new and old waterproofing materials, even if the materials themselves are the same. As described in Non-Patent Document 1 and Japanese Patent Publication No. 2008-106598 (Patent Document 1), this mechanical fastening method is a groundbreaking waterproofing repair method that uses fastening brackets to install new waterproofing materials. The specific construction procedure involves forming a waterproofing layer by partially fixing the new and old waterproofing materials, as well as the building structure itself, using anchors, discs, etc., regardless of the condition of the existing waterproofing layer. This technology eliminates the compatibility between new and old waterproofing materials. Furthermore, by using an air-powered driving machine to fasten the fastening brackets, the construction speed is increased, contributing to shorter construction periods and cost reductions. As a result, waterproofing manufacturers have shifted their focus to mechanical fastening methods as a labor-saving waterproofing repair method. In the waterproofing market, particularly for rooftops of building structures, a common belief has even emerged that the only waterproofing repair method using the overlay method is the mechanical fastening method.

[0005] The overlay adhesive method using vulcanized rubber sheets is a technique for completely bonding and fixing new and old waterproofing materials. Liquid materials such as adhesives and primers are commonly used for this complete fixing. These materials must be suitable for bonding new and old waterproofing materials. However, wet-type adhesives and primers require a drying and curing time after application before proceeding to the next step. Furthermore, the adhesives used for newly installed vulcanized rubber sheets contain organic solvents. If these adhesives containing organic solvents are applied directly to existing hot asphalt or modified asphalt sheets, they will dissolve the existing waterproofing material, hindering the waterproofing repair. Therefore, when combining new and old waterproofing materials, insulation is necessary between the layers. Substrate preparation materials such as resin mortar are used for insulation. These materials are inorganic materials composed of cement and silica sand. Other resins include epoxy and urethane. These inorganic materials, resins, and water are mixed to undergo a chemical reaction, ultimately forming a hardened product. Similar to the adhesives and primers mentioned earlier, this also requires proper drying after application before proceeding to the next step. This drying process involves a waiting period. These are all disadvantages of waterproofing repairs using wet-type substrate preparation materials. Many substrate preparation materials, such as resin mortar, cannot be used for the next step on the same day they are applied. Furthermore, the drying and curing time depends on the film thickness of the substrate preparation material and the ambient temperature, and this curing time affects the overall construction period.

[0006] As mentioned earlier, the mechanical fastening method using an overlay system has become common in recent years, but this method also has its drawbacks. For example, because the mechanical fastening method partially fixes the new waterproofing material using fastening brackets, there is a concern that the fixing strength to the existing waterproofing material will be reduced compared to the adhesive method which uses adhesive to fix the entire surface. This reduction in fixing strength can lead to damage to the new waterproofing material due to natural weather conditions (especially strong winds). Examples of damage include tearing and peeling of the new waterproofing material near the fastening brackets, and cases where the joints of the sheets open up and peel off due to wind. In addition, there were environmental problems caused by the construction, such as noise generated by the machinery when fastening the fastening brackets, and concerns that asbestos contained in the building structure may be scattered to the surrounding area. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2008-106598 [Non-patent literature]

[0008] [Non-Patent Document 1] Guide to Rooftop Renovation Using Sheet Waterproofing, published by the Synthetic Polymer Roofing Association (2006) [Overview of the project] [Problems that the invention aims to solve]

[0009] There is a need for proposals for waterproof repair methods and structures that use the overlay method without the inconveniences associated with the aforementioned wet-type substrate preparation materials and mechanical fastening methods. [Means for solving the problem]

[0010] In order to solve the above problems, this invention was developed through diligent research, utilizing a dry-type asphalt sheet or other dry-type leveling sheet as a base preparation material (leveling sheet) for waterproofing repairs, and using a vulcanized rubber-based sheet as a new waterproofing material. In other words, the waterproof repair structure of the present invention is as follows: (1) A waterproof repair structure for an existing waterproof layer, wherein a new waterproof layer made of vulcanized rubber sheet is laid and fixed on the upper surface of the existing waterproof layer via a dry-type leveling sheet. (2) The waterproof repair structure according to (1), wherein the existing waterproof layer is an asphalt waterproof layer. (3) The waterproof repair structure according to (2), wherein the asphalt waterproof layer is a hot asphalt waterproof layer or a modified asphalt waterproof layer. (4) The dry-type leveling sheet is a modified asphalt sheet. Waterproof repair structure as described in any of (1) to (3). (5) The waterproof repair structure according to (4), wherein the modified asphalt sheet is provided with a solvent-resistant film on its upper surface. (6) The waterproof repair structure according to (4) or (5), wherein the modified asphalt sheet comprises a reinforcing fiber layer within the sheet. Furthermore, the waterproofing repair method of the present invention is as follows: (7) A waterproofing repair method for an existing waterproofing layer, comprising the steps of laying and fixing a dry-type leveling sheet on the upper surface of the existing waterproofing layer, and then laying and fixing a vulcanized rubber sheet on the upper surface of the dry-type leveling sheet. (8) The waterproofing repair method described in (7), wherein the existing waterproofing layer is an asphalt waterproofing layer. (9) The dry-type leveling sheet is a modified asphalt sheet. Waterproof repair method as described in (7) or (8). (10) The waterproof repair method according to (9), wherein the modified asphalt sheet is provided with a solvent-resistant film on its upper surface. (11) The waterproof repair method according to (9) or (10), wherein the modified asphalt sheet comprises a reinforcing fiber layer within the sheet. (12) The dry-type unevenness adjustment sheet is laid and fixed on the upper surface of the existing waterproof layer after applying an adhesive or attaching a shaped seal to the upper surface of the existing waterproof layer in the waterproof repair method according to any one of (7) to (11). (13) The vulcanized rubber-based sheet is laid and fixed after applying a rubber-based adhesive to the upper surface of the dry-type unevenness adjustment sheet in the waterproof repair method according to any one of (7) to (12).

Effect of the Invention

[0011] The waterproof repair method and its structure of the present invention limit the newly installed waterproof material to a vulcanized rubber-based sheet and use a dry-type base adjustment material (unevenness adjustment sheet) such as a shaped modified asphalt sheet. This method, unlike the wet-type base adjustment material, does not require a curing time or waiting time until drying and enables continuous construction, leading to a shortening of the construction period of the waterproof repair work. In addition, the unevenness on the surface of the base is alleviated by the flexibility of the sheet, and the effect of finishing the surface of the vulcanized rubber-based sheet into a smooth surface can be obtained. Also, there is no concern about noise during construction or the scattering of asbestos like in the mechanical fixing method. This waterproof repair method can fully adhere the dry-type base adjustment material (unevenness adjustment sheet) and the vulcanized rubber-based sheet. Therefore, the resistance to strong winds is improved, and the occurrence of damage caused by the scattering of the sheet can be reduced. In addition, by providing a solvent-resistant film on the upper surface of the dry-type unevenness adjustment sheet, the construction period can be shortened.

Brief Description of the Drawings

[0012] [Figure 1] It is an explanatory drawing showing the waterproof repair method of the present invention. [Figure 2] It is an explanatory drawing showing the waterproof repair method of the present invention. [Figure 3] It is an explanatory drawing showing the waterproof repair structure of the present invention. [Figure 4] It is a cross-sectional explanatory drawing of the unevenness adjustment sheet used in the waterproof repair method of the present invention. [Figure 5] It is an explanatory drawing of the adhesion test of the waterproof repair structure of the present invention. [Figure 6]It is an explanatory diagram of the adhesion test of the waterproof repair structure of the present invention.

Embodiments for Carrying out the Invention

[0013] The waterproof repair method and its structure of the present invention utilize a dry-type unevenness adjustment sheet such as dry-type modified asphalt as a base adjustment material and use a vulcanized rubber sheet as a new waterproof material. That is, the waterproof repair method of the present invention comprises a step of laying and fixing a dry-type unevenness adjustment sheet on the upper surface of an existing waterproof layer, and then a step of laying and fixing a vulcanized rubber sheet on the upper surface of the dry-type unevenness adjustment sheet. Further, the waterproof repair structure of the present invention is a waterproof repair structure in which a new waterproof layer of a vulcanized rubber sheet is laid and fixed on the upper surface of an existing waterproof layer via a dry-type unevenness adjustment sheet.

[0014] Figure 1 is an explanatory diagram showing the steps of the waterproof repair method of the present invention. In the figure, 1 indicates a base composed of RC concrete or the like. An existing waterproof layer 2 made of hot asphalt, modified asphalt, or the like is laid on the upper surface of the base 1. According to the waterproof repair method of the present invention, first, a rubber asphalt-based adhesive 3a is applied in a dot pattern at a coating amount of 0.5 kg / m 2 on the upper surface of the existing waterproof layer 2, and then a dry-type unevenness adjustment sheet 4 made of a modified asphalt sheet with a thickness of about 4 mm is laid and fixed on the upper surface of the existing waterproof layer 2. Although an example of applying the rubber asphalt-based adhesive 3a in a dot pattern has been shown, it may be applied over the entire upper surface of the existing waterproof layer 2. Figure 2 shows an example in which, instead of the dot-shaped adhesive 3a in Figure 1, a long strip-shaped shaped sealing material 3b mainly composed of butyl rubber is attached to the upper surface of the existing waterproof layer 2. After attaching the shaped sealing material 3b to the upper surface of the existing waterproof layer 2 in this way, a dry-type unevenness adjustment sheet 4 made of a modified asphalt sheet is laid and fixed on the upper surface of the existing waterproof layer 2. Next, as shown in Figure 3, a rubber-based adhesive is applied as a dedicated adhesive 5 at a coating amount of 0.2 kg / m 2The dry leveling sheet 4, to which the special adhesive 5 has been applied, is then laid and fixed as a vulcanized rubber sheet 6 with an adhesive layer of 1.0 to 2.0 mm thickness to obtain the waterproof repair structure of the present invention. For the special adhesive 5 mentioned above, it is preferable to use a chloroprene rubber-based or butyl rubber-based adhesive. The aforementioned unevenness adjustment sheet has a waterproofing function and is therefore also effective as a temporary waterproofing material. In particular, the 4mm thick uniform material unevenness adjustment sheet is highly flexible and, when applied to a substrate, has the effect of mitigating the unevenness of the substrate. Furthermore, it follows the elongation characteristics of the movement and does not crack or break. In this embodiment, a finishing paint 7 compatible with the rubber sheet, or the aforementioned finishing paint 7 mixed with silica sand, is applied to the entire upper surface of the vulcanized rubber sheet 6 at a rate of 0.2 kg / m². 2 ~0.5 kg / m 2 I decided to apply it that way.

[0015] As shown in Figure 4, the surface of the unevenness adjustment sheet is coated with a solvent-resistant special film layer 4a made of resin that has been processed to prevent dissolution by the organic solvent of the special adhesive 5. This special film layer 4a has good affinity with the special adhesive 5 and is compatible with the vulcanized rubber sheet 6 of the newly installed waterproofing material. The processing treatment can include lamination or other processing treatments. The solvent-resistant special film layer 4a can be polyethylene resin, modified acrylic resin, polyethylene terephthalate resin, etc., with the use of polyethylene terephthalate resin being preferred. In the figure, 4b represents a reinforcing fiber layer made of synthetic fibers. Thus, the dry asphalt sheet 4 becomes stronger by having a reinforcing fiber layer 4b within the sheet. The reinforcing fiber layer 4b can be polyester nonwoven fabric, glass cloth, or a combination thereof, with the use of polyester spunbond being preferred.

[0016] Next, an adhesion test was conducted between the unevenness adjustment sheet 4 and the vulcanized rubber sheet 6 in the waterproof repair structure of the present invention. As shown in Figure 5, a rubber asphalt adhesive 3a is applied to the base 1, which is made of slate boards, at a rate of 0.5 kg / m². 2 After applying the material to the entire surface, a leveling sheet 4 made of modified asphalt sheet is laid and fixed in place, and then a rubber-based adhesive 5 is applied on top of it at a rate of 0.2 kg / m 2 After application, a vulcanized rubber sheet 6 was laid and fixed to prepare the test sample. The obtained test samples were left to stand at room temperature for 3 days, then placed in a 70°C constant temperature bath for 30 days, and finally placed in a 70°C constant temperature bath for 60 days. Tests were then conducted under each of these conditions. The adhesion test was conducted according to the Peel Adhesion Strength Test Method - Part 2: 180-degree Peel Test JIS K 6854-2:1999, and the adhesion strength was measured using an autograph. The test specimens were cut into strips 25 mm wide. The peeling speed of the specimens was set to 200 mm / min, and the average value of three specimens was used as the test result. The test results obtained are shown in Table 1. Note that the units of the values ​​in the table are N / 25mm.

[0017] [Table 1]

[0018] The test results revealed that the adhesive strength was above the standard value of 10.

[0019] Next, an adhesion test was conducted between the existing waterproofing layer 2 and the unevenness adjustment sheet 4 in the waterproofing repair structure of the present invention. As shown in Figure 6, a modified asphalt sheet is laid and fixed as an existing waterproof layer 2 on a base 1 made of slate boards, and an asphalt-based adhesive 3a is applied to the upper surface at a rate of 0.5 kg / m 2 After applying the material to the entire surface, a leveling sheet 4 made of modified asphalt sheet was laid and fixed in place to prepare a test sample. The samples were tested under the following conditions: after being left to stand at room temperature for 3 days, then placed in a 70°C constant temperature bath for 30 days, and finally placed in a 70°C constant temperature bath for 60 days. The adhesion test was conducted according to the Peel Adhesion Strength Test Method - Part 2: 180-degree Peel Test JIS K 6854-2:1999, and the adhesion strength was measured using an autograph. The test specimens were cut into strips 25 mm wide. The peeling speed of the specimens was set to 200 mm / min, and the average value of three specimens was used as the test result. The test results obtained are shown in Table 2. Note that the units of the values ​​in the table are N / 25mm.

[0020] [Table 2]

[0021] The test results revealed that the adhesive strength was above the standard value of 10. [Industrial applicability]

[0022] By providing a waterproof repair method and waterproof structure using a wet-type substrate preparation material and mechanical fastening method that avoids inconveniences, this method is industrially useful. [Explanation of Symbols]

[0023] 1. Primer 2 Existing waterproofing layer 3a Adhesive 3b Standard-shaped stickers 4. Dry-type leveling sheet 4a Special film 4b Reinforcement fiber layer 5. Special adhesive 6. Vulcanized rubber sheet 7. Finishing paint

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