JP2915257B2 - How to install steel shoring - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of installing a steel shoring, and more particularly to a method of installing a steel shoring provided on an inner peripheral surface of a tunnel and supporting earth pressure from an outer ground. .

[0002]

2. Description of the Related Art A tunnel supporter is a support structure built in a tunnel to hold the ground from excavation to lining. One of these tunnel supports is to bend steel materials such as H-section steel and steel pipes according to the cross-sectional shape of the tunnel, and to erection this along the inner peripheral surface of the excavated tunnel. There are steel supports that make up the tunnel, by installing a large number of such steel supports at predetermined intervals in the longitudinal direction of the tunnel, and by spraying concrete between adjacent steel supports. Maintain the ground over the entire length of the.

However, since the inner peripheral surface of the tunnel immediately after excavation has irregularities and the surface is not flat, when a steel shoring is erected along the inner peripheral surface of the tunnel, the leg portion of the steel shoring is required. There will be a gap between this and the surrounding ground. As a method for preventing the steel support from becoming unstable due to such a gap, conventionally, for example, a method of packing a wooden board, an iron plate, or the like between the bottom surface of the leg portion of the steel support and the bottom surface of the tunnel. Has been adopted.

[0004]

However, in the above-mentioned method using a wooden board or an iron plate or the like, a flat wooden board or an iron plate or the like having no flexibility is merely packed in the gap, so that the method is not applicable to the bottom ground having irregularities. In addition, it is difficult to sufficiently remove the gap between the steel support and the ground around the legs other than the portion where the wooden board or the iron plate is packed, while leaving a gap. Therefore, these gaps cause the legs of the steel shoring to sink, and the stability of the steel shoring,
As a result, there was a problem that the whole tunnel could not be stabilized.

[0005] In addition, the ground near the legs of the steel shoring is removed by excavation of the tunnel, the ground above it is removed, the applied earth pressure is removed, and the stress is released. Is in a loose situation. Therefore, when a steel shoring is built on such a loose ground, when the installation of the steel shoring is completed and the load of the ground around the tunnel is applied, the steel shoring sinks. There was a problem of fear.

Accordingly, the present invention has been made in view of the above problems, and when a steel shoring is to be built in a tunnel, a gap between the leg of the steel shoring and the ground around it is provided. It is an object of the present invention to provide a method of installing a steel supporter that can easily and reliably prevent sinking of a leg portion of a steel supporter and instability of a tunnel by filling a gap easily and reliably.

Another object of the present invention is to provide a method of installing a steel supporter which can easily prevent the settlement of the supporter from sinking due to loosening of the ground of the leg of the steel supporter.

[0008]

According to the present invention, there is provided a method of installing a steel supporter which is disposed on an inner peripheral surface of a tunnel and supports earth pressure from an outer ground, wherein the steel supporter is connected to a tunnel. It is built along the inner circumference of the cross-section and along the shape of the gap in the gap between the leg of the steel support and the ground around it.
An injectable material having fluidity such as mortar and concrete and solidifying after a lapse of a predetermined time is injected into the bag via an injection means attached to the bag, with an inflatable bag interposed in a three-dimensional direction. The bag is pressed and inflated with the pouring material so that the bag is closely interposed between the leg of the steel support and the ground. Installation method.

[0009]

According to the method of installing a steel supporter of the present invention, when the steel supporter is installed in the tunnel, a bag is inserted between the leg of the supporter and the surrounding ground supporting the leg. Intervene the body. Next, an injection material such as mortar is injected into the bag via injection means such as a pressure-resistant hose provided in the bag, and the bag is pressurized and expanded by the injection material. As a result, the bag filled with the injection material is closely interposed between the steel support leg and the ground, and the injection material is filled in the gap between the support leg and the ground around the support leg. The inside of the gap can be adapted to the shape of the gap, and thereby the gap can be easily and reliably filled. Therefore, after the injection material is solidified, the tunnel can be stably supported without sinking of the steel support due to the gap around the leg.

Further, since the bag body is pressurized and expanded by the injection of the injection material, a preload is loaded on the steel support and the ground around the legs thereof by the pressure, whereby the ground is compacted. Prevent subsidence of shoring due to loose ground.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

FIGS. 1A and 1B are schematic sectional views showing an example of a steel supporter 10 built in a tunnel 11 according to an embodiment of a method of installing a steel supporter of the present invention. .

In this embodiment, the steel support 10 is formed into an arch shape in accordance with the cross-sectional shape of the tunnel 11, and the H-shaped steel 1, 1, which is divided into right and left, is provided only in the upper half of the tunnel 11. It is a so-called half-section type built in
Many are installed at regular intervals in the longitudinal direction of the excavated tunnel 11. The steel support 10 has its legs 2 placed on the ground E on the upper side wall located at the lower end surface of the upper half of the tunnel 11, and transmits the load to the ground E. It supports the load of the ground applied from the surroundings.

Since it is difficult to excavate the ground E around the leg portion 2 on which the steel supporter 10 is placed according to the shape of the leg portion 2, FIG. As shown in the drawing, a gap S is formed between the leg portion 2 and the ground E due to the unevenness, and the steel support 10 may sink after the load from the ground is loaded by the gap S. . Therefore, in this embodiment, the gap S between the leg portion 2 and the ground E around the leg portion 2 is filled by the following method.

That is, as shown in FIG. 1C, when the steel support 10 is installed in the tunnel 11, the steel support 1
The bag 3 is interposed between the ground 0 and the ground E. At this time, the bag 3 is disposed between the leg 2 and the ground E in advance before the steel support 10 is erected. The bag 3 is made of a flexible material, for example, synthetic fiber cloth, thin metal, synthetic resin, or the like, and expands due to internal pressure. A pressure-resistant hose 4 as an injection means for injecting the material 6 into the bag body 3 is connected.

After the steel support 10 is installed, the injection material 6 is injected into the bag body 3 through the pressure hose 4 as shown in FIG. As the injection material 6, a material having fluidity at the time of injection and solidifying to a strength sufficient to support a load applied to the leg portion of the steel support 10 after a predetermined time has elapsed;
For example, a hardening material such as mortar, concrete, and urethane can be used.

Then, by the pressurizing and filling operation, the flexible bag 3 is pressurized and inflated, and the filling material 6 is easily and surely filled over the corners of the gap S. And closely interposed between the leg 2 of the steel support 10 and the ground E. In addition, the bag body 3 is
The steel support 10 is pushed up or pressed against the ground E by being pressurized and expanded between the ground E and the ground E, thereby tightening the loose ground E released from the earth pressure by excavation. It is possible to harden and, after the injection material is hardened, it is possible to uniformly transmit the load applied to the steel support 10 to the ground.

In this embodiment, the bag 3 is further provided with a return hose 5 (FIG. 1C,
(D)). This return hose 5 allows the injection of the injection material 6 to be performed more quickly by appropriately removing the internal air when the injection material 6 is injected, and the inside of the injection material 6 by the air remaining inside. This is to prevent bubbles from being formed in the air.

FIGS. 2A to 2D show another embodiment of the present invention. In this embodiment, the present invention is applied to a full-section steel support (see FIG. 2A). When a horseshoe-shaped steel support 13 is installed, the legs of the steel support 13 are used. The bag 3 is interposed between the portion 8 and the bottom ground E 'of the tunnel to fill a gap S' generated between them, and the injection material 6 is injected into the bag 3 by pressure. In this embodiment as well, the gap S 'between the leg portion 8 and the ground E' is filled, and after the injection material 6 has hardened, the steel support works without sinking as in the above-described embodiment. 13 can be uniformly transmitted to the ground E ′, and the load of the ground around the tunnel can be stably supported by the steel support 13.

[0020]

As described in detail above, according to the method for installing a steel supporter of the present invention, a gap is provided between the foot of the steel supporter built in and the ground around it. Along the shape
By interposing a bag that can be inflated three-dimensionally by injecting an injectable material into the bag and compressing and expanding the bag,
The gap between the foot of the steel support and the ground can be easily and reliably filled, so that after the injection material has solidified, the steel support due to the gap around the foot can be used. Subsidence can be reliably prevented, and the tunnel can be stably supported.

The bag interposed between the steel support leg and the ground is pre-loaded on the steel support and the ground around the leg by expanding under pressure by injecting an injection material. Thus, the loosened ground can be compacted to more reliably prevent the steel support from subsidence.

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory view showing one embodiment of a method of installing a tunnel support according to the present invention, wherein (A) is a cross-sectional view of a tunnel 11 and (B) is an explanatory view of a steel support 10. Yes,
(C), (D) is an explanatory view of the injection operation of the injection material 6.

FIG. 2 is an explanatory view showing another embodiment of the installation method of the tunnel support according to the present invention, wherein (A) is a cross-sectional view of the tunnel 11 and (B) is an explanatory view of a steel support 13. (C) and (D) are illustrations of the operation of pouring the pouring material 6.

[Explanation of symbols]

 2 legs 3 bag 4 pressure-resistant hose (injection means) 6 injection material 10, 13 steel support 11 tunnel E, E 'ground S, S' gap

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hideaki Nishiura 2-3-3 Kandaji-cho, Chiyoda-ku, Tokyo Obayashi Corporation Tokyo Head Office (72) Inventor Iwao Nakahara 15-17 Sakuraokacho, Shibuya-ku, Tokyo Japan Foundation Within Technology Co., Ltd. (72) Inventor Shin Minoi 6-22, Matsugaeda-cho, Kita-ku, Osaka-shi, Osaka Japan Basic Technology Co., Ltd. (56) References JP-A-4-231599 (JP, A) (58) Field surveyed (Int.Cl. ⁶ , DB name) E21D 11/18

Claims (1)

(57) [Claims] 1. A method of installing a steel supporter disposed on an inner peripheral surface of a tunnel and supporting earth pressure from an outer ground, wherein the steel supporter is constructed along an inner peripheral surface of a cross section of the tunnel. Between the steel support and the ground around it.
An injectable material having fluidity such as mortar and concrete and solidifying after a predetermined time elapses in the bag is interposed with a bag which can be inflated in a three-dimensional direction along the shape of the space in the space. By injecting through the attached injecting means and pressurizing and expanding the bag with the injection material, the bag is closely interposed between the leg of the steel support and the ground. A method of installing a steel shoring, characterized by the following.