JP3225285U - Waterproof sheet with scratch detection function - Google Patents

Abstract

An object of the present invention is to provide a defect detection function for a NATM method which does not require labor such as lamination in production, as well as being able to easily detect breakage of a sheet surface (loss of waterproofness) even from a remote place. Provide a tarpaulin.
A waterproof sheet (1) includes a non-woven fabric water-permeable layer (3), and a synthetic resin single-layer waterproof layer (2) disposed so as to be in contact with one surface of the water-permeable layer (3). The surface in contact with the waterproof layer 2 is formed on the colored layer 31 that exhibits a strong contrast with respect to the color of the waterproof layer 2.
[Selection diagram] Fig. 1

Description

  The present invention relates to a waterproof sheet that is useful mainly for tunnel construction in which construction is performed by the NATM method, and more specifically, when the construction is performed, the surface is damaged by sharp corners of the construction surface or a reinforcing bar, and the waterproofness is reduced. The present invention relates to a waterproof sheet having a flaw finding function that can easily detect or detect damage with the naked eye.

  The waterproofing sheet used in the NATM method covers the primary lining constructed on the ground excavated along the cross-sectional shape of the tunnel from above, applies a secondary lining, and places it on the secondary lining side. It is used to prevent water such as spring water seeping from the ground to leak to the secondary lining side.

  The waterproofing sheet used in the above-described embodiment is, when covering the primary lining surface, scratched by the sharp irregularities of the primary lining surface or a reinforcing bar arranged for the secondary lining, and may be broken small. However, it was extremely difficult to detect such damage with the naked eye from the outer surface of a transparent or translucent synthetic resin waterproof sheet having a thickness of about 0.8 to 2 mm.

  In particular, the top side of the primary lining approach surface in the tunnel under construction is far away from the eyes of construction personnel who are visually observable, and there is not enough lighting because it is inside the tunnel under construction, so small damage to the waterproof sheet Finding it with the naked eye was painful.

  In view of these points, Patent Literature 1 and Patent Literature 2 propose technologies for easily finding small damage to the sheet as a waterproof sheet for the NATM method, but these proposed technologies still have to be solved. It turned out to be an issue.

  That is, the waterproof sheet of Patent Literature 1 forms a composite sheet by adhering a thin sheet of a light or light color to a surface of a base sheet of a dark or dark color, and forms the surface of the composite sheet with a roughened surface. However, after preparing two molded sheets, these two sheets are pasted, that is, laminated, and furthermore, the surface of the thin sheet is processed into a roughened surface with irregularities. In terms of labor costs, the cost was higher than that of a single-layer sheet. Further, when the waterproof sheet described in Patent Document 1 is stretched at a waterproofing construction site with the base sheet side facing back, when the waterproof sheet is torn, the base sheet at the torn location has a dark or dark color and a bright front surface sheet. Alternatively, it can be easily found by two tones with a pale color, but when the composite sheet is cut sharply, the base sheet is not exposed and the permeable layer is in contact with the base sheet. The nonwoven fabric sometimes appeared. When the water-permeable layer had a color that did not exhibit two tones in relation to the thin sheet, a broken portion could not be easily found.

  On the other hand, the waterproof sheet of Patent Document 2 has a sheet-like light-emitting layer (light-emitting sheet) in which a light-emitting substance particle that emits a light-emitting phenomenon due to electromagnetic wave irradiation is dispersed in a water-impermeable layer (that is, a single-layer waterproof sheet). Although it is laminated and joined, not only does it take time to manufacture the luminescent sheet, but it also has to be laminated on the water-impermeable layer. The disposable material buried between the primary lining and the secondary lining of the tunnel was economically problematic.

Japanese Patent Publication No. 5-68566 Japanese Patent No. 4182361

  Therefore, in the present invention, even if the waterproof sheet is installed between the primary lining and the secondary lining in the NATM method, it may be rubbed with the primary lining surface at the time of the construction of the sheet or may be formed with the reinforcing steel for the secondary execution. Not only is it possible to easily detect damage to the sheet surface (loss of waterproofness) that may occur due to catching, etc. even from a remote location. It is an object to provide a waterproof sheet having a discovery function.

  The structure of the waterproof sheet having a flaw finding function of the present invention made for the purpose of solving the above-mentioned problem is made of a non-woven permeable layer, and a synthetic resin made of a synthetic resin arranged to be in contact with one surface of the permeable layer. A single waterproof layer, wherein the surface of the water permeable layer that is in contact with the waterproof layer is formed as a colored layer that exhibits strong contrast with respect to the color of the waterproof layer.

  The colored layer can be formed by attaching a dye or pigment to the water-permeable layer, and is formed by forming the nonwoven fabric from a material that exhibits strong contrast with respect to the color of the waterproof layer. You can also.

  The waterproof sheet having a flaw detection function of the present invention includes a non-woven fabric permeable layer and a synthetic resin single-layer waterproof layer arranged so as to be in contact with one surface of the permeable layer. Since the surface in contact with the waterproof layer is formed as a colored layer that exhibits a strong contrast with the color of the waterproof layer, in the tunnel construction of the NATM method, a permeable layer is arranged on the primary footwear side. Therefore, when the waterproof layer is arranged on the secondary lining side, even if the waterproof sheet hits a reinforcing bar or the like and is torn, the colored layer is exposed by the tear, so from a remote place. However, the breakage of the waterproof sheet can be easily detected with the naked eye.

  In particular, since the waterproof sheet of the present invention is formed of a non-woven fabric permeable layer and a synthetic resin single-layer waterproof layer, the laminating step is not required for the production of the waterproof sheet, which is a large economical and process-saving. There are significant advantages.

FIG. 4 is a plan sectional view of the wall surface of the NATM tunnel using the waterproof sheet of the present invention. FIG. 2 is a front view schematically showing a case where the waterproof sheet of FIG. 1 has a scratch that impairs waterproofness. FIG. 3 is a front view schematically showing a case where a single-layer waterproof sheet according to a comparative example has a scratch similar to that shown in FIG. 2.

Next, an embodiment of the waterproof sheet 1 having a flaw finding function of the present invention (hereinafter simply referred to as the waterproof sheet 1) will be described with reference to the drawings.
As shown in FIG. 1, the waterproof sheet 1 according to the present embodiment includes a waterproof layer 2 and a water-permeable layer 3 arranged to be in contact with one surface of the waterproof layer 2.
The waterproof sheet 1 is used in a state where the waterproof layer 2 is directed to the secondary footwear side of the NATM method and the water-permeable layer 3 is directed to the primary footwear side.
The water-permeable layer 3 has a colored layer 31 that expresses contrast due to a difference in brightness from the waterproof layer 2 at least on a surface in contact with the waterproof layer 2. Therefore, it is possible to confirm that the waterproof layer 2 has been broken by confirming that the colored layer 31 is exposed from the secondary footwear side.
Hereinafter, each component will be described.

The waterproof layer 2 is formed of a pellet or powder of EVA resin (Ethylene Vinyl Acetate Polymer) copolymerized with ethylene and vinyl acetate as main components, and has a thickness of 0.8 mm to 2.0 mm and is opaque. It is formed in the shape of a sheet.
The waterproof layer 2 is formed so as to have a higher brightness than the colored layer 31 in order to express contrast by a difference in brightness from the colored layer 31. In the present embodiment, since the colored layer 31 is black as described later, the colored layer 31 is formed in white to exhibit strong contrast.
Although the waterproof layer 2 is formed in white in the present embodiment, the waterproof layer 2 may be formed in white color including milky white or the like in addition to white. Also in this case, contrast can be developed for the color of the colored layer 31.

The waterproof layer 2 is a single-layer sheet formed in one step. Like a known multi-layer sheet, each sheet is formed in the first step, and then the first sheet is formed in the second step. Since there is no need to perform two steps such as laminating another second sheet to form a multilayer sheet, there is a great economical and process-saving advantage.
The waterproof layer 2 is attached to the surface of the water-permeable layer 3 on which the colored layer 31 is formed.

The permeable layer 3 is usually formed of a non-woven cloth having a thickness of 3 mm or more.
As the material of the nonwoven fabric, natural fibers, chemical fibers, inorganic fibers, and the like can be used.
Natural fibers include animal hair such as cotton, hemp or silk, or wool. Examples of the chemical fiber include those formed of a synthetic resin such as polyester, polypropylene, and polyethylene. Examples of the inorganic fiber include those formed of glass, metal, ceramic, and the like.
The water-permeable layer 3 has a colored layer 31 formed on at least a surface in contact with the waterproof layer 2.

The colored layer 31 is formed on a part of the surface of the water-permeable layer 3 facing the waterproof layer 2 of the water-permeable layer 3.
The colored layer 31 is formed so as to have a lower brightness than the waterproof layer 2 in order to express contrast by a difference in brightness from the waterproof layer 2. In the present embodiment, the colored layer 31 is formed in black.

The colored layer 31 is formed by attaching a dye or pigment to the surface of the water-permeable layer 3 facing the waterproof layer 2.
A known method such as coating, spraying, and dyeing can be appropriately selected as the method of adhesion.
In the case of dip dyeing, a dye or a pigment is attached to the entire permeable layer 2 so that the colored layer 31 can be easily formed on the entire permeable layer 2.

  The waterproof sheet 1 configured as described above has a structure in which the waterproof layer 2 faces the secondary footwear side during tunnel construction, and the water-permeable layer 3 faces the primary footwear side such that the colored layer 31 faces the waterproof layer 2. When it is placed on the primary lining surface, the reinforcing layer or the like for the secondary footing collides with the waterproofing layer 2 or is pressed against the ground (the primary footing surface) having sharp irregularities, and the waterproofing layer 2 If it is damaged or torn, it will impair its waterproofness. In the state where the waterproof layer 2 is torn or damaged in this way, as shown in FIG. 2, the black color of the colored layer 31 is visible in the tear Gv of the waterproof layer 2, that is, the white waterproof layer 2 is torn. Since the black colored layer 31 looks like a “cut line shape” in the portion, it is possible to find that the waterproof sheet 2 is torn at a glance with the naked eye even from a distant place.

  Incidentally, in the sheet 5 of the comparative example having a waterproof layer made of a white synthetic resin and a water-permeable layer made of a white non-woven fabric shown in FIG. 3 and having no colored layer formed on the water-permeable layer, the sheet of FIG. Even if there is a scratch (rip Gv) similar to that of the waterproof sheet 1 of the invention, it is extremely difficult to visually recognize the tear Gv because the water-permeable layer of the sheet 5 is white.

  As described above, the preferred embodiment of the present invention has been described. In addition to this, the configuration described in the above embodiment may be selected or changed to another configuration as appropriate without departing from the gist of the present invention. be able to.

  For example, in the present embodiment, the colored layer 31 is formed by attaching a pigment or a dye to the water-permeable layer 3, but the present invention is not limited to this. The water-permeable layer 3 may be formed by forming the colored layer 31 on the water-permeable layer 3 by forming the nonwoven fabric from a material that exhibits contrast with respect to the color of the waterproof layer 2. As the material of the nonwoven fabric, for example, a material whose color itself expresses a contrast with respect to the color of the waterproof layer 3 or a material which is colored in advance so as to exhibit a contrast with respect to the color of the waterproof layer 3 Can be used. Thereby, there is a great economical and process-saving advantage that a step of attaching a pigment or a dye to the water-permeable layer 3 becomes unnecessary.

  In the present embodiment, the waterproof layer 2 is previously adhered to the surface of the water-permeable layer 3 on which the colored layer 31 is formed, but the present invention is not limited to this. At the time of tunnel construction, first, the water-permeable layer 3 may be arranged with the colored layer 31 facing the secondary footwear side, and then the waterproof layer 2 may be arranged so as to be in contact with the colored layer 31.

Furthermore, in the present embodiment, the contrast is expressed by the difference in brightness between the waterproof layer 2 and the colored layer 31, but the present invention is not limited to this. The contrast may be expressed by a difference in saturation between the waterproof layer 2 and the colored layer 31. In this case, it is desirable that the saturation of the colored layer 31 be sufficiently lower than the saturation of the waterproof layer 2.
Furthermore, the contrast may be exhibited by one of the colors of the waterproof layer 2 and the colored layer 31 having a complementary color relationship or a substantially complementary color relationship of a hue circle with the other color.

The waterproof sheet having a flaw finding function according to the present invention used for tunnel construction constructed by the NATM method is a non-woven permeable layer 3 and a synthetic resin single layer arranged so as to be in contact with one surface of the permeable layer 3. The water-permeable layer 3 has a surface in contact with the waterproof layer 2 formed on the colored layer 31 that exhibits a strong contrast with respect to the color of the waterproof layer 2. For this reason, it is not necessary to form a waterproof sheet through a laminating process into two waterproof sheets 2 each formed like a sheet having a conventional flaw detection function into one waterproof sheet. Very advantageous.
And the waterproof sheet 1 of the present invention has an effect that even if the waterproof layer 2 is manufactured in one step, the tear and the like can be easily detected with the naked eye similarly to the two-layer waterproof sheet that has passed through the laminating step. Since it plays, it is extremely useful as a waterproof sheet used for tunnel construction by the NATM method.

DESCRIPTION OF SYMBOLS 1 Waterproof sheet 2 Waterproof layer 3 Water permeable layer 31 Colored layer Gv Split

Claims (3)

A non-woven permeable layer,
A single-layer waterproof layer made of synthetic resin disposed so as to be in contact with one surface of the water-permeable layer,
The waterproof sheet having a flaw finding function, wherein a surface of the water permeable layer that is in contact with the waterproof layer is formed as a colored layer that exhibits strong contrast with respect to the color of the waterproof layer.   The waterproof sheet according to claim 1, wherein the colored layer is formed by attaching a dye or a pigment to the water-permeable layer.   The waterproof sheet according to claim 1, wherein the nonwoven fabric is formed of a material that exhibits a strong contrast with respect to the color of the waterproof layer.

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