JPS59498A - Application of concrete to all cross area of tunnel - 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 entire cross-section concrete lining construction method of the tunnel of the present invention, especially the new Austrian tunnel construction method, that is, New++Au
mtr(an□Tunnhl 1・lnl Metho
d (hereinafter abbreviated as N) relating to a construction method using K.

One of the characteristics of this construction method, which is becoming increasingly popular, is the primary lining.

In other words, spraying uses concrete, rock bolts, wire mesh, lightweight steel shoring, or other supporting materials, either alone or in combination, to construct a semi-rigid, thin-walled lining on the other mountain surface immediately after excavation. By doing so, it is possible to suppress the loosening of the ground as much as possible and make full use of the natural supporting capacity of the ground.

In other words, the special feature of the NATM concept is to make maximum use of the inherent support capacity of the ground around the tunnel after excavation, and to select a lining that is compatible with this. new<
Therefore, the secondary lining concrete roll can be made thinner and more economical.

According to NArM, tunnel safety is achieved by secondary lining concrete, and in order to obtain high tunnel safety, thin secondary lining concrete must be placed in close contact with the primary bond surface. That is important. In that case, −
The legal lining surface and the secondary lining are concise. - Insulation between the double structural elements consisting of the secondary construction surface and the secondary lining concrete.
The pedestal prevents friction between the two when the earth load is applied,
The ground load is applied to the secondary I-econcrete in fractions,
This is because it reduces the bending moment generated in the secondary lining concrete. If the bending moment is small, the thin-walled secondary lining concrete will not lose its safety over a long period of time.

Conventionally, when applying NATM, impermeable municipal water sheets are the primary material in geological formations with spring water. ◆A construction method is used in which an insulating layer, that is, an anti-friction layer, is applied between the construction surface and the secondary lining concrete, and between the 7th and 2nd 4th stanchions. Originally, an impermeable water stop sheet with a thickness of 0.4 fl would be sufficient to achieve the purpose of stopping water, but since it was used as a layer that also serves as an anti-friction layer, it has been used to improve the anti-friction effect. The thickness is gradually increasing, 1.5 va
A water-stop sheet with a thickness of 100 mm came to be used, and from a few years ago, a non-woven fabric with a thickness of 6 to 8 mm was sandwiched between the primary lining surface and the water-stop sheet in order to make the friction prevention even more effective. Therefore, there is a trend towards placing secondary 1st concrete. This insulating layer made of non-woven fabric acts as a cushioning material and plays an effective role in preventing friction when earth loads are applied. At this time, its water permeability also contributes to drainage at the back of the secondary lining concrete. For example, if the applied rock load is 60 tons/-/, the thickness will be about 100 ton, but the water permeability will not be too bad.

That is, when adopting NATM, which has spring water, the combined use of the above-mentioned nonwoven fabric and a water-stop sheet is an extremely preferable construction method. However, this is based on the idea that the cushioning, which effectively prevents friction, and the water stoppage for drainage from the back of the lining are performed in separate layers, and the water leakage, drainage from the back of the lining, and effective friction. It cannot be oversimplified in that it is necessary to install two layers of nonwoven fabric and 1-hydrocarbon sheet to prevent the problem.

The present invention eliminates the drawbacks of the prior art described above, and provides two methods for constructing a full-section concrete tunnel using NATM, which can easily achieve water stoppage, drainage from the back of the lining, and effective friction prevention. The purpose is to

The construction method of the present invention is to use NATM water-stop sheets, which have discontinuous one-year protrusions dotted over the entire surface with rubber-like elasticity on one side, when constructing the entire cross-section of the tunnel with concrete.
The method is characterized in that after placing the convex part on the surface of the first concrete surface with the convex part facing the second surface, the second concrete is poured.

According to the present invention, by constructing the water-stop sheet with the above-mentioned protrusions and protrusions tTI≦A1, not only the purpose of water-stopping is achieved, but also the space between the protrusions and protrusions of the sheet is reduced. The drainage hole on the back side of the secondary concrete lining is useful because its ridges have a rubber-like elasticity and are formed over the entire surface of the sheet, so when external loads are applied, It works as a very self-help mechanism.

Therefore, according to the present invention, it is guaranteed that water stoppage, drainage on the back side of the lining, and effective prevention of friction can be achieved with +m cleanliness by applying only a single layer of waterstop sheet.

Furthermore, since the protrusions and convex portions in the IL water receipt of the present invention are discontinuous, it can be stretched in a state that is well adapted to the irregularities of the primary lining surface of the ground surface.

In the present invention, the same material as the conventionally known water stop sheet in NATM can be used for city water sheet with raised portions,
The thickness of the non-ridged portion of the small water sheet can be varied within a wide range, but generally 4 mm or 4 mm is sufficient. The thickness of the raised portion of the water stop sheet can be varied over a wide range, but generally it is about 3 to 5 thick. The total area of is variable over a wide range of iiJ, but generally the size is l/] angle (
Alternatively, (the size of the shape 111 corresponding to 1), the total area of chess may be 1-1 Φ1'L area of 1 area of the entire sheet.

Below, the implementation side of the present invention will be explained with reference to the drawings (1
) indicates a water-stop sheet, and the sheet (1) has discontinuous protrusions and recesses (2) having rubber-like elasticity formed in 1 dots over the entire surface of one side.

Direct excavation of the ground (3) and NATM method-covering (
4) according to the usual method, and then attach the water-stop seam 1-(tl) to the above-mentioned water-stop seam 1-(tl) in accordance with the usual method. At this time, the edges of the adjacent water stop sheet and city water sheet are joined by a method known per se,
After that, the secondary lining concrete IJ-t5) is poured.

The tunnel thus constructed is highly safe, with water-tight properties, drainage at the back of the tunnel, and anti-friction properties. (6) is due to the space between the protrusions (2) and (2).
This is the drainage passage behind the lining.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway slope view showing an example of the IL water receipt used in the present invention, Fig. 2 is a sectional view showing an example of the construction method of the present invention, Fig. 3 is a partially enlarged view of Fig. 2 of I/I It is. (1) is the IL water receipt (2) is the protrusion and convex part, (3
) is ground, (4) is - law cover, (5)
(6) is drainage passage, (above) Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] ■ Entire cross-section of tunnel concrete) During the tII construction,
A water-stop sheet in which discontinuous ridges and ridges having rubber-like elasticity are formed dotted over the entire surface on one side is used as the primary construction surface using the new Austrian tunneling method, and the ridges and ridges are then A full-section concrete lining construction method for tunnels characterized by placing secondary lining concrete after lining the concrete on the construction side.