JP2004019178A - Impervious lining structure of tunnel and steel box-shaped segment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an excavating soil drying method and its dryer for surely drying excavated soil on the spot by effectively utilizing the function of a self-traveling excavator normally used at a job site. <P>SOLUTION: In this impervious lining structure 1 of tunnel, the lining structure is basically composed of a segment 2 composed of a high density clay type soil material 5. Actually, the segment is formed in a steel box 4 having the opening base rock side, and is constituted by filling the high density clay type soil material 5 inside, and is applied to an impervious plug in a segment structure in a shielding construction method or an underground facility of radioactive waste. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
TECHNICAL FIELD The present invention relates to a water-impervious lining structure and a steel box-shaped segment of a tunnel that completes watertightness and lining of a water-impervious plug by establishing water-tightness in a tunnel.
[0002]
[Prior art]
Preventing vegetation change due to lowering of water level on the ground surface due to tunnel spring water Tunnel key points to prevent leakage of harmful substances such as tunnel construction in specific areas and underground facilities for radioactive waste In underground tunnel construction where it is necessary to install water-blocking plugs, water-tightness that ensures watertightness is required.
[0003]
However, in conventional tunnel construction, cement-based lining materials are used for lining and shields. Will be required.
[0004]
In other words, it is not practical to use a lining with perfect water-blocking performance in a general tunnel, so the cement lining material is used for the tunnel lining material. In the case of the shield method, concrete segments are often used. However, in the former case, it is impossible to completely crack the concrete, and thus it is impossible to construct a complete water-proof lining. In the latter case, waterproofness can be ensured by sandwiching a sealing material such as rubber between the joints of the segments.However, since the cracks in the secondary lining concrete cannot be reduced to zero, complete waterproofing It is difficult to build a mechanic.
[0005]
As shown in FIG. 3, the water-impedance plug for the underground tunnel installed in the underground facility for radioactive waste has a water-impedance plug 11 that satisfies the following conditions in the tunnel 10 at key points. A small amount of harmful nuclides leaking from the waste body into the groundwater is prevented from leaking into the living area on the ground surface through the tunnel 10 as a water path.
[0006]
However, the impermeable plug 11 needs to solve the following problems.
{Circle around (1)} The water barrier performance deteriorates due to alteration or dissolution in groundwater over a long period of time.
{Circle around (2)} Since a region with increased water permeability is generated in the loosened area around the tunnel, it is necessary to install a widening plug having a larger cross section than the standard cross section.
{Circle around (3)} The support material and lining structure for stably maintaining the tunnel space with a large cross section deteriorate the water blocking performance over a long period of time.
{Circle around (4)} It is not possible to suppress the area of increased permeability in the loose area around the tunnel.
[0007]
For this reason, the water-impervious plug 11 formed in the plug construction section and provided with the manhole 12 is made of a high-quality natural clay which is a material that is easy to secure water-impermeability without deterioration over a long period of time. Bentonite is used. The compressed bentonite 13 is formed into a shell structure by assembling segments on both sides with a steel partition form plate 14 and a tie rod bolt 15, and is contracted by a tunnel support structure 16 configured in a shell structure. .
[0008]
During construction of the impermeable plug 11, construction is being promoted while utilizing the manhole 12, but after the construction is completed, the manhole 12 is closed with high-quality natural clay bentonite.
[0009]
However, a lining structure 17 made of ordinary concrete is installed before and after the water-blocking plug 11, and a cement-based material is used for the tunnel lining structure 17. There is a concern that the components may elute and chemically alter the bentonite of the water shield plug 11.
[0010]
Bentonite is of high quality during the period in which Na ions are predominant in exchangeable cations, whereas performance deteriorates when Ca ions are predominant. Therefore, the water barrier in the tunnel 10 lacks reliability.
[0011]
Therefore, in underground tunnel construction where a waterproof plug is provided in a tunnel construction in a specific area or a radioactive waste underground facility, water-tightness that ensures watertightness is required, but the above problem is completely solved. At present, there is no provision for the impermeable lining structure of the tunnel.
[0012]
[Problems to be solved by the invention]
The present invention proposes an improved structure in view of the above-mentioned current situation, and a water-blocking lining structure of a tunnel that completes water-tightness and lining of a water-blocking plug by establishing water-blocking in the tunnel. It offers steel box segments.
[0013]
[Means for Solving the Problems]
The impermeable lining structure of the tunnel according to the present invention comprises a lining structure composed of segments made of a high-density clay-based soil material. It is constructed by filling with soil material. The tunnel lining structure may be a shell structure formed by assembling segments, or a water-impedance plug in a radioactive waste underground facility, and the shell structure formed by assembling the segments may be backed with bentonite or slurry. Features.
[0014]
Further, the steel box-shaped segment according to the present invention is a segment used for the water-impermeable lining structure of the tunnel, and is a steel box formed by opening the rock side and a high-density box filled in the steel box. It is composed of clay soil materials.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
The impermeable lining structure of the tunnel according to the present invention is configured by arranging a segment filled with a high-density clay-based soil material inside a steel box having an open rock side, and forming a steel box-shaped segment. Watertightness in tunnels is established by using a steel box formed with the rock side open and a high-density clay-based soil material filled in the steel box.
[0016]
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described in detail below with reference to the drawings.
[0017]
FIG. 1 shows an embodiment of a perspective view of a water-impermeable lining structure of a tunnel and a partially extracted steel box-shaped segment according to the present invention. The water impermeable lining structure 1 according to the present invention is not specified at the front and rear joining positions of a plurality of steel box-shaped segments 2 described later. It is constructed in a cylindrical or shell structure to ensure watertightness.
[0018]
The steel box-shaped segment 2 is formed into a steel box 4 having a predetermined shape adapted to a lining cylindrical shape or a shell structure in a state where the outer side 3 is opened by processing a steel plate. The steel box 4 is formed as a single steel box-shaped segment 2 by filling the entire outer surface of the steel box 4 with bentonite 5 which is a high-density clay-based soil material.
[0019]
FIG. 2 is a state diagram illustrating the state of aging of the impermeable lining structure according to the present invention.
[0020]
In the figure, FIG. 2A shows a state where the steel box-shaped segment 2 is arranged on the rock face 6, and a slight gap 7 is provided between the steel box-shaped segment 2 and the rock face 6. Bentonite is present while leaving. It is sufficient that the gap 7 formed between the steel box-shaped segment 2 and the rock face 6 is such that the workability can be smoothly performed, and is not so large as to be exaggerated in the drawing. In particular, when the lining structure of the tunnel is a shell structure formed by assembling the steel box-shaped segments 2, it is also effective to perform backing according to a general construction method.
[0021]
As a backing material at this time, a mixed material of bentonite and water or a bentonite-based slurry material such as a mixed material of bentonite, ethanol, and water is suitable. By filling the space between the rock surface and the rock surface 6, the gap is sealed.
[0022]
FIG. 2 (b) shows a state in which the impermeable lining structure 1 has been appropriately aged. When groundwater from the rock surface 6 has penetrated toward the tunnel, it becomes a water droplet 8 and becomes a steel box. When the groundwater is permeated and absorbed by the bentonite, or when the gap is filled with the bentonite-based slurry material, the groundwater is also permeated and absorbed by the bentonite-based slurry material by dropping onto the bentonite 5 filled in the shaped segment 2. become. As a result, the bentonite 5 and the bentonite-based slurry material of the steel box-shaped segment 2 absorb water and expand, thereby sealing the water space between the steel box-shaped segment 2 and the rock face 6. In addition, since the expansion of the bentonite 5 also seals the joint between the steel box-shaped segments 2, the water-blocking performance of the lining structure 1 is reliably exhibited, and the shell structure of the segments is backed. In such a case, these functions will be further enhanced.
[0023]
Bentonite is a material that has been stably present in natural underground environments for more than hundreds of thousands of years, and if there is no nearby material that produces a chemical impact such as cement, it will have a long-term soundness. Although it can be expected, it does not exhibit mechanical strength by itself, but it can sufficiently exhibit desired strength by filling the steel box-shaped segment 2 as in the present invention. The box-shaped segment 2 functions as a support structure until the tunnel is backfilled.
[0024]
Furthermore, the swelling of the bentonite is achieved by filling the water path space between the steel box-shaped segment 2 and the rock face 6 to reduce the permeability to a very small value of 1E-8 m / s to 1E-13 m / s. It blocks the water path of groundwater, and at the same time, does not have any water passage due to cracks like cement-based materials.
[0025]
And, since the water-impermeable lining structure and the steel box-shaped segment of the tunnel according to the present invention do not use any cement-based material, the elements that deteriorate the bentonite alteration are removed and the steel material is used for a long time. Even if the volume becomes zero due to corrosion in the middle, the bentonite that swells the space where the steel material has disappeared seals it and prevents the generation of water channels, ensuring the establishment of tunnel water barrier. .
[0026]
As described above, the present invention has been described in detail based on the embodiment. However, the impermeable liner structure and the steel box-shaped segment of the tunnel according to the present invention are not limited to the above-described embodiment. It goes without saying that various modifications can be made to the specific structure, material, etc. of the form, segment, etc. without departing from the spirit of the present invention.
[0027]
【The invention's effect】
The impermeable lining structure of the tunnel according to the present invention comprises a lining structure composed of segments made of a high-density clay-based soil material. It is constructed by filling with soil material. The tunnel lining structure may be a shell structure formed by assembling segments, or a water-impedance plug in a radioactive waste underground facility, and the shell structure formed by assembling the segments may be backed with bentonite or slurry. Because of the features, it has the effect of perfecting watertightness and lining of the water-blocking plug by establishing water-blocking in the tunnel.
[0028]
Further, the steel box-shaped segment according to the present invention is a segment used for the water-impervious lining structure of the tunnel, and is a steel box formed by opening the rock side and a high-density steel filled in the steel box. Since it is composed of clay-based soil material, it has the effect of providing an effective segment to complete the watertightness and the lining of the water-blocking plug by establishing water-blocking in the tunnel.
[Brief description of the drawings]
FIG. 1 is a diagram showing an embodiment of a water-impervious lining structure of a tunnel and a steel box-shaped segment according to the present invention. FIG. 2 is an aging diagram of a steel box-shaped segment according to the present invention. FIG. Schematic diagram of impermeable plugs in underground facilities in Japan [Description of symbols]
1 impermeable lining structure, 2 steel box-shaped segment, 3 outside, 4 steel box 5 bentonite, 6 bedrock surface, 7 gap, 8 water drop,
10 tunnel, 11 impermeable plug, 12 manhole,
13 bentonite filler, 14 steel partition form plate,
15 Tie rod bolt, 16 Tunnel support structure, 17 Lining structure,

Claims (6)

An impermeable lining structure for a tunnel, wherein the lining structure is composed of segments made of a high-density clay-based soil material. 2. The tunnel liner lining structure according to claim 1, wherein the segments are formed in a box shape with the rock side open and filled with a high-density clay-based soil material. 3. The tunnel impermeable lining structure according to claim 1, wherein the lining structure of the tunnel is a shell structure formed by assembling segments. 4. 3. The tunnel lining structure according to claim 1, wherein the tunnel lining structure is a waterproof plug in a radioactive waste underground facility. 4. The tunnel water-proof lining structure according to any one of claims 1 to 4, wherein the lining structure of the tunnel is a shell structure formed by assembling the segments, and is backed with bentonite and slurry. A steel box formed by opening the rock side and a high-density clay-based filler filled in the steel box, the segment being used for the water-impermeable lining structure of the tunnel according to any one of claims 1 to 5. A steel box-shaped segment composed of soil materials.

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