JPH10159495A - Lining method of inside wall of tunnel and lining structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase workability, by spraying a waterproof layer on a waterpermeable layer in which an organic compound containing bubbles having specified composition and properties is sprayed on a concrete surface. SOLUTION: A compound containing particles, a binder, and a foaming agent is sprayed on the concrete surface of the inside wall of a tunnel to form a waterpermeable layer. And an adhesive waterproof layer is sprayed thereon. The compound contains a binder having a quantity corresponding to 10-30 volume % in porosity with respect to particles of 30-50 volume % in porosity, and a foaming agent enough to retain a fluid state, by which the mixture of the particles and the binder can be sprayed. The water permeability coefficient of the waterpermeable layer is made to be 10<-2> cm/sec or more and the compressive strength is made to be 5kgf/cm<2> or more. The particles are selected from aggregate such as silica sand, wooden chips, rubber chips, resin beads, metallic grit, etc., for instance. And an adhesive such as epoxy resin or the like is used as the binder. The foaming agent is selected from surfactants. In this way, the inside wall of a tunnel can be coated by only a spraying process without laying sheets.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for lining a tunnel inner wall and a lining structure. More specifically, in the waterproofing method of the inner wall of the tunnel, the permeable layer forming the waterproof layer can be formed by a spraying machine without using a manual operation as in the prior art, and the tunnel inner wall lining method and the forming method are used. To a tunnel inner wall lining structure.

[0002]

2. Description of the Related Art As a waterproofing method for tunnel construction on mountain roads, NATM was used in the late 1975's.
(New Austrian Tunneling Method)
However, it is established as a standard method that can be almost completely waterproof. In the NATM method, as shown in FIG. 1, a sprayed concrete layer (1) is formed on the entire inner wall of a hole excavated in the ground, and then a fixed size water-permeable cushioning material (such as a nonwoven fabric) (2a)
And impermeable sheet (EVA or PVC etc.) (2b)
The waterproofing sheet is constructed by attaching the ends of the waterproofing sheet made of the above to each other while overlapping each other, forming a waterproofing layer (2), and further forming a lining concrete layer (3) on the surface thereof.

[0003] The spring water that seeps out of the sprayed concrete layer cannot pass through the impermeable sheet, but is absorbed by the water-permeable cushioning material and guided to the drain 4 at the bottom of the tunnel to be discharged. Water leakage from the surface is reliably prevented, and indirect cracking is also prevented. In addition, the water-permeable cushioning material layer of the waterproof sheet absorbs the impact during construction of the lining concrete and the surface roughness of the sprayed concrete layer, thereby preventing water leakage due to damage to the non-water-permeable sheet.

[0004] When attaching a waterproof sheet by the NATM method, a fixed size (about 2 m width) of a water-permeable cushioning material is fixed with nails or the like while overlapping the ends thereof, and the non-water-permeable sheets are attached to each other. The overlapping portion is joined by heat welding or the like on site using high frequency or a press with a built-in heater. Build a scaffold in the tunnel, and use the non-permeable sheet with a long total extension distance with high reliability so that the presence of the pillars will be partially adapted to the uneven inner peripheral surface of the tunnel due to the presence of bolts and nuts for pillar support. The process of attaching the waterproof sheet to the entire inner periphery of the tunnel while completely performing the joining of the overlapped portions is a difficult operation requiring time and effort. Attempts are being made to simplify this work and to form the waterproof sheet layer by a method using a spraying machine in the same manner as spraying concrete.

For example, Japanese Patent Application Laid-Open No. Sho 62-236996 discloses that
Next, a high-foamable urethane elastomer is sprayed on the entire surface of the concrete to form a primary waterproof coating having the same function as the cushioning material, and a low-foamable or non-foamable urethane elastomer is sprayed on the first waterproof coating to impermeable to water. It describes a method for forming a secondary waterproof coating having the same function as a sheet, and a method for simplifying a process of forming a waterproof layer only by spraying work.
This method does not provide the primary waterproofing film with the function of water permeability, and when the urethane is blown and foamed, the primary waterproofing film is waterproofed together with the skin layer formed between the foam and the primary concrete surface. The purpose of the present invention is to provide the function described above, and it cannot be directly applied to the simplification of the NATM method.

Therefore, a method of spraying a water-permeable cement mortar (foamed mortar or an inorganic porous composition) as a water-permeable layer, and spraying urethane (solid or foam) or an acrylic emulsion as a waterproof sheet thereon, followed by curing. And the like have been proposed (JP-A-7-173997).

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for lining an inner wall of a tunnel in which a waterproof sheet comprising a water-permeable layer and a non-water-permeable layer can be provided more simply by a spraying process. , And a tunnel inner wall lining structure.

[0008]

Means for Solving the Problems The present inventors sprayed a layer in which various particles having a porosity sufficient to provide water permeability were fixed with a minimum amount of binder not impairing the water permeability. Considering that it would be installed on shotcrete by the work of attachment, we studied diligently. When spraying the particles and a small amount of the binder, the most important problem is the fixing ratio of the mixture of the particles and the binder to the wall surface during the spraying. The inventors of the present invention set the fixing rate at 70% as a standard, and in order to further increase the fixing rate, it is effective to increase the fluidity of the mixture by generating bubbles which disappear when the binder is cured in the mixture. It has been confirmed that it is effective to use a small amount of a foaming agent such as a surfactant to generate such foam. In addition, the permeable layer thus formed smoothes the irregularities of cm order seen on the sprayed concrete surface to the order of mm, and does not require the weighting step required by the conventional construction method of pasting and constructing the cushioning material, and the next step It was confirmed that the formation of the water-impermeable layer could be performed by spraying. The present invention has been completed based on such findings.

That is, the present invention provides: 1) A foam-containing composition containing particles, a binder, and a foaming agent that keeps a mixture of the particles and the binder in a flowable state capable of being sprayed on the surface of the concrete sprayed on the inner wall of the tunnel. Spraying to form a water permeable layer, and then forming an adhesive waterproof layer on the water permeable layer by spraying, 2) a method for covering the inner wall of the tunnel, 2) for particles having a porosity of 30 to 50% by volume. Spraying a foam-containing composition containing a binder equivalent to 10 to 30% by volume of the porosity and a foaming agent in an amount sufficient to keep the mixture of the particles and the binder in a sprayable fluid state. 3) The tunnel inner wall lining method according to 1 above, wherein a water permeability coefficient of the water permeable layer is 10 ⁻² cm / sec or more (according to the Tokyo method for drainable pavement) and a compressive strength of 5 kgf /
cm ² or more (JISA1216), the tunnel inner wall lining method according to 1 above, 4) the tunnel inner wall lining method as described in 1 above, using aggregate particles, 5) silica sand, glass beads, The tunnel inner wall lining method according to the above 4, wherein the method is selected from at least one of ceramic spheres, wood chips, rubber chips, resin beads, metal grids, and calcium carbonate. 6) The method according to the above 1, wherein an adhesive is used as a binder. Tunnel inner wall lining method 7) The adhesive is selected from the group consisting of epoxy resin, acrylic resin, modified silicone resin, acrylonitrile-butadiene-styrene rubber resin, vinyl acetate emulsion, and ethylene-vinyl acetate copolymer emulsion. 8) The tunnel inner wall lining method described in 8), wherein the foaming agent is selected from surfactants. Method 9) A water-permeable layer formed by spraying a foam-containing composition containing a tunnel inner wall sprayed concrete layer, particles, a binder, and a foaming agent that keeps a mixture of the particles and the binder in a sprayable fluid state. And a waterproofing layer formed by spraying on the surface of the permeable layer, and a tunnel inner wall lining structure, and 10) the permeable layer is formed by the method according to any of the above 2 to 6. 10. The tunnel inner wall lining structure according to 9 above, which is a layer.

Hereinafter, the present invention will be described in detail. Formation of a primary concrete layer: In the present invention, formation of a primary lining concrete layer in a tunnel is performed according to a conventional technique. For example, for 1 m ^{2 of} concrete, about 300 kg of cement, about 1100 kg of sand, about 900 kg of crushed stone
Then, about 10 kg of a quick setting agent is pressure-fed with air, and water corresponding to 45 to 55% by weight of cement is sprayed on the tunnel excavation surface while mixing the mixture with water at a tip nozzle portion. The sprayed concrete begins to solidify and solidify in several tens of seconds to several minutes, forming a primary concrete layer.

Formation of a water-permeable layer: (1) Particles The particles used in the formation of a water-permeable layer in the present invention adhere to primary concrete with an appropriate strength when sprayed with an appropriate amount of a binder, and after the binder is cured. The layer to be formed has an appropriate water permeability. Specifically, the porosity [(Vm−Vt) / Vm) × 100% determined by measuring the apparent volume Vm and the true volume Vt of the particles is 25 to 7
0, preferably 40-50% stable particles,
In addition, the compression strength after curing of the binder (according to JIS A1216) is 3 kgf / cm ² or more, preferably 5 kgf / cm ^2.
cm ² or more. If the porosity is more than 70%, the aggregate has a large grain system, and irregularly shaped ones cause poor fixation. Such particles include, for example, silica sand (3 to 6
No.), glass beads (0.6 to 5.5 mm), ceramic cobblestone (2 to 20 mm), wood chips, rubber chips, resin beads,
Examples include metal grids and inorganic particles such as calcium carbonate. Among these, silica sand and ceramic spheres are preferred.

(2) Binder When the binder used for the water-permeable layer is used together with the above particles and cured, the binder has a compressive strength (J) of 5 kgf / cm ² or more.
ISA1216), which is stable for a long period suitable for the intended use. Examples of such a binder include a polymer-based adhesive. Specific examples include an epoxy resin, an acrylic resin, a silicone-modified polymer, an acryl-butadiene-styrene rubber-based resin, a vinyl acetate emulsion, and an ethylene-vinyl acetate copolymer emulsion. Of these, epoxy resins are preferred. The amount of the binder used is such that the layer obtained by curing the particles to a required strength and curing and consolidation is 10 ⁻² cm
Per second (measured in accordance with the Tokyo Metropolitan Law for drainage pavement). Specifically, the porosity of the particles (40 to 50)
%), Which is equivalent to about 10 to 30%. If the amount of the binder is less than 10% with respect to the porosity, fixation at the time of spraying will be poor, and if it exceeds 20%, the water permeability will decrease, which is not preferable.

(3) Foaming agent In the present invention, the particles and a small amount of the binder are sprayed onto the intended predetermined place with a high fixing rate, so that the mixture has a property of increasing the fluidity of the mixture and the binder is cured. And a foaming agent that stably generates foam that disappears when the mixture is produced. Examples of foaming agents that generate such foams include anionic, cationic, amphoteric or nonionic surfactants, as well as silane coupling agents.

Examples of the anionic surfactant include soaps such as sodium laurate, sodium stearate and sodium oleate; higher alcohol sulfates, higher alkyl ether sulfates, sulfated oils, sulfated fatty acid esters, and the like. Sulfates such as sulfated fatty acids and sulfated olefins; alkylbenzene sulfonates, alkylnaphthalene sulfonates, paraffin sulfonates, Igepon T (trade name), aerosol OT
Sulfonates such as (trade name); phosphates such as higher alcohol phosphates;

Examples of the cationic surfactant include amine salt-type cationic surfactants such as higher alkylamine salts, and quaternary ammonium salt-type cationic surfactants such as alkyltrimethylammonium salts and alkyldimethylbenzylammonium salts. Examples of the amphoteric surfactant include amino acid-type amphoteric surfactants, stearyl dimethylyl betaine, betaine-type amphoteric surfactants such as lauryl dihydroxyethyl betaine,

Examples of the nonionic surfactant include a polyethylene glycol type nonionic surfactant and a polyhydric alcohol type nonionic surfactant. Anionic surfactants, which are excellent in foaming properties and stable in foaming, and higher alcohol sulfates such as sodium polyoxyethylene lauryl ether sulfate are preferred.

In the present invention, an amphoteric surfactant is used in combination as a foam stability enhancer. The amount of foaming agent used is
The amount of the mixture of the particles and the binder is sufficient to show fluidity that can be sprayed by a spraying machine due to the adsorptive power of the generated foam surface. Although it depends on the type of the binder and the additive, it is generally 2 to 10 parts by weight, preferably 2 to 5% by weight based on 100 parts by weight of the binder.

(4) Other Additives In the present invention, a thickener and a thixotropic agent are used as necessary to further enhance the adhesion between the binder and the particles. Examples of the thickener include cellulose and the like of the thixotropic agent include silica, talc, and clay.

(5) Spraying of the water-permeable layer At the time of spraying, the particles, the binder and the additives are stirred and mixed to generate stable bubbles, and then charged into a spraying machine (spraying robot). Spray on the object. As the spraying machine, a spraying gun machine usually used in construction work, in particular, a spraying gun machine used for spraying small and medium particle lysine, skin and lightweight spraying material can be preferably used. The sprayed water-permeable layer material depends on the type of binder. For example, when an epoxy resin is used, the water-permeable layer is cured in 2 to 5 hours to form a water-permeable layer. The thickness of the water-permeable layer formed by spraying varies depending on the condition of the environmental ground, the size of the tunnel, and the like, but about 3 to 5 mm is sufficient.

Formation of a water-impermeable layer: In the present invention, the water-impermeable layer formed by spraying on the water-permeable layer is a material which can be sprayed and has sufficient space between the water-permeable layer and the water-permeable layer. Any material may be used as long as the material has an adhesive strength. Preferred examples of such a material include a two-component thermosetting resin and a one-component moisture-curable resin. For the spraying of the non-permeable layer, a high-pressure mixing sprayer combined with a propeller gun, a two-liquid mixing and discharging spray device equipped with a mixer, and the like can be used. For example, a waterproof layer formed of a two-part, fast-curing polyurethane cures instantaneously and can be used even in cold regions. The formed waterproof layer has sufficient strength, abrasion resistance, It has excellent hardness, chemical resistance, etc., has smooth continuity, and can reliably cover the secondary concrete in the next step.

Formation of secondary concrete layer: A lining concrete is cast on the waterproof layer by a conventional method. For example, first, using a wooden or steel material frame, an assembling or movable form is installed, and then concrete is driven in by a machine using a pressure pump. After curing and curing this concrete for about one day, the mold is removed to form a lining concrete.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to examples. Examples 1 to 6 and Comparative Examples 1 to 64 No. 4 silica sand (porosity: 45%), epoxy adhesive, or vinyl acetate aqueous adhesive and foaming agent (sodium polyoxyethylene lauryl ether sulfate) are shown in Table 1 and Table 2
The mixture is mixed by a machine at the ratio shown in
It was sprayed on a concrete plate of mx 30 cm x 2 cm and left standing at room temperature for 24 hours to cure to form a water-permeable layer having a thickness of 2 to 5 mm. At this time, the spraying workability, the water permeability of the formed water-permeable layer, the adhesion to the sample surface, and the compressive strength of the cured layer were measured and evaluated by the following methods. The results are shown in Table 1 (Comparative Example) and Table 2 (Example).

Next, Limspray F-1000 (manufactured by Mitsui Toatsu Chemicals, Inc.) which is a two-part urethane elastomer.
The liquid A and the liquid B are supplied to the two-liquid mixing and discharging spray device at a pressure of 100 kg / cm ² , respectively.
And sprayed on the surface of the sample formed in the above example to form a water-impermeable layer. The adhesion strength between the impermeable layer and the permeable layer thus formed was measured and evaluated by the following method. The results are shown in Table 2. The impermeable layer formed had a specific gravity of 1.1 and a hardness of 90 (Shore).
A), tensile strength 132 kg / cm ² , tensile elongation 400%, water permeability (above according to JIS K6301) 1
0 ^-6 or less, indicating no water permeability.

Spraying workability: When the composition shown in Table 1 or Table 2 was mixed, it was observed whether or not spraying was possible with a spraying machine (whether or not the composition had sufficient fluidity for spraying). Evaluation was made according to the following criteria. …: When the cup is turned upside down, the liquid flows continuously.…: There is a mixture of continuous and discontinuous states.…: Drops discontinuously.

Water permeability: A water permeability test was carried out in accordance with the Tokyo Metropolitan Law for drainage pavements, and judged according to the following criteria. …: 10 ⁻² cm / sec or more, ×: less than 10 ⁻² cm / sec.

Adhesion to sample surface: Fixing rate was calculated from the weight of the material mixture adhered by spraying to the sample plate whose weight was measured in advance and the weight of the compound charged in the spraying machine, and evaluated according to the following criteria. did. …: Fixing rate of 70% or more, Δ: Fixing rate of 50 to 70%, ×: Fixing rate of less than 50%.

Compressive strength of cured layer: A test specimen having a diameter of 50 (mm) and a height of 100 mm was prepared, measured according to JIS A1216, and judged according to the following criteria. ○ ...... 5kgf / cm ² or more, △ ...... 3~5kgf / cm ^2, less than × ...... 3kgf / cm ^2. Adhesive strength: Measured according to JIS K 5400 (unit: kgf / cm ² ).

[0028]

[Table 1]

[0029]

[Table 2]

From the results in Tables 1 and 2, it can be seen from the results that only the particles and the adhesive (binder) were used (Comparative Examples 1 to 3: epoxy-based,
In Comparative Examples 4 to 6: aqueous vinyl acetate), even if the amount of the binder is changed, there is a problem in any of spraying workability, water permeability, and adhesion to a surface. When a foaming agent (surfactant) is added to the adhesive, spraying workability, water permeability, and adhesion to the surface are improved, and there is no problem in using it as a water-permeable layer of the tunnel lining structure. It was confirmed that performance was obtained. Also,
It was confirmed that a solid impermeable layer could be formed on this permeable layer.

[0031]

According to the present invention, a bubble-containing composition containing particles, a binder, and a foaming agent for keeping a mixture of the particles and the binder in a sprayable fluid state is sprayed by a spraying machine. A tunnel lining method and a tunnel lining structure for forming a permeable layer are provided. According to the method of the present invention, the water-permeable layer and the waterproof layer can be formed only by the spraying step, and the workability is improved and the construction period can be greatly reduced as compared with the conventional method of attaching a waterproof sheet.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a tunnel constructed by the NATM method.

[Explanation of symbols]

 1 sprayed concrete layer 2 waterproof layer 3 lining concrete layer 4 drainage ditch

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Osamu Wakisaka 3600, Gezu, Kita-gaiyama, Komaki-shi, Aichi Prefecture Inside Tokai Rubber Industries Co., Ltd. 3600 Tokai Rubber Industries Co., Ltd.

Claims (10)

[Claims] 1. A permeable layer formed by spraying a foam-containing composition containing particles, a binder, and a foaming agent that keeps a mixture of the particles and the binder in a sprayable fluid state on a surface of the concrete sprayed on the inner wall of the tunnel. And then forming an adherent waterproof layer on the water-permeable layer by spraying. 2. The method according to claim 1, wherein the binder having a porosity of 30 to 50% by volume and a binder equivalent to 10 to 30% by volume of the porosity and a mixture of the particles and the binder are kept in a fluid state capable of being sprayed. The tunnel inner wall lining method according to claim 1, wherein the water-permeable layer is formed by spraying a cell-containing composition containing a sufficient amount of a foaming agent. 3. The water permeability of the water-permeable layer is 10 ⁻² cm / sec or more (according to the Tokyo method for drainable pavement), and the compressive strength is 5%.
^2. The tunnel inner wall lining method according to claim 1, wherein the tunnel inner wall lining is at least kgf / cm ² (JISA1216). 4. The method according to claim 1, wherein particles of aggregate are used. 5. The aggregate is selected from one or more of silica sand, glass beads, ceramic cobblestone, wood chips, rubber chips, resin beads, metal grids, and calcium carbonate.
Tunnel inner wall lining method described in 4. 6. The method according to claim 1, wherein an adhesive is used as a binder. 7. The adhesive according to claim 6, wherein the adhesive is selected from an epoxy resin, an acrylic resin, a modified silicone resin, an acrylonitrile-butadiene-styrene rubber-based resin, a vinyl acetate emulsion, and an ethylene-vinyl acetate copolymer emulsion. Tunnel inner wall lining method. 8. The method according to claim 1, wherein the foaming agent is selected from a surfactant. 9. A concrete layer sprayed on a tunnel inner wall;
A water-permeable layer formed by spraying a bubble-containing composition containing particles and a binder and a foaming agent that keeps a mixture of the particles and the binder in a sprayable fluid state, formed by spraying on the surface of the water-permeable layer. A tunnel inner wall lining structure having a waterproof layer. 10. The tunnel inner wall lining structure according to claim 9, wherein the permeable layer is a layer formed by the method according to any one of claims 2 to 6.