JPH0414599A - Structure and construction method of branch part of underground 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] <Industrial Application Field> The present invention relates to a branch section of a plurality of underground horizontal tunnels of different heights, and a structure and method for constructing the branch section through a vertical shaft. It is related to.

<Conventional technology> Shield construction methods and propulsion construction methods are often used when constructing public ditches, water and sewage systems, etc. in cities.

These construction methods have the advantage of being able to construct pipes underground without affecting the ground.

<Problems to be Solved by the Present Invention> However, the above-mentioned construction method also has the following problems, which limits the scope of its use.

<B> In many cases, the underground branch of an intersection is the branch point of a pipe.

However, many existing underground structures are often concentrated at intersections, making it extremely difficult to open above ground for work.

〈Talking〉For this purpose, the freezing method is used, which involves freezing the surrounding ground, reinforcing it, and cutting it open, but it is expensive and uneconomical.

<Objective of the present invention> The present invention was made in order to improve the above-mentioned problems, and an object thereof is to provide the following structure and construction method of an underground tunnel junction.

(a) Structures and methods that can be used without affecting the above ground even in areas where underground structures are concentrated, such as intersections. A structure and method that can be constructed in
A structure that connects other horizontal tunnels of different heights underground, with a vertical tunnel built downward from the bottom of one horizontal tunnel and another tunnel connected via the lower part of this vertical tunnel. This is the structure of an underground tunnel branch made up of:

Furthermore, the present invention improves the ground around a horizontal tunnel constructed underground, then reinforces the inside of the vertical portion of the horizontal tunnel that is planned to be constructed, dismantles the floor members of that portion, and then uses the exposed ground after the demolition. This is a method of constructing underground tunnel branches by excavating a vertical shaft while protecting the surrounding area and reinforcing the inside of the vertical shaft with concrete.

<Description of the present invention> The present invention will be described in detail below in accordance with the order of construction.

<B> Construction of a horizontal tunnel (Fig. 1) A horizontal tunnel 1 is constructed underground using the shield method and propulsion method.

Pipe bodies such as hume pipes and concrete segments can be used as construction members for this tunnel 1, but in order to facilitate the construction of this construction method, it is efficient to use steel pipes at least in the planned vertical area. Let me explain the case.

<Exit> Ground improvement (Figure 2) The surrounding ground will be improved at the planned vertical construction site.

To do this, a poling device 2 is installed in the horizontal tunnel 1, a hole is drilled underground through the wall surface, and a chemical solution is injected from inside the horizontal tunnel 1 toward the surrounding area.

<C> Reinforcement of steel pipes (Fig. 3) The surrounding area will be reinforced in preparation for demolition of the bottom of the horizontal shaft.

Examples of reinforcing methods include fixing the upper part of the horizontal tunnel 1 with a diameter facing outward and reinforcing the vertical upper part during excavation.

Furthermore, in order to reinforce the opening during excavation, the upper half of the horizontal tunnel is held from below by an arcuate ring 4 made up of H and li.

Further, a horizontal girder 5 is stretched over the maximum horizontal diameter portion of the horizontal tunnel 1 to reinforce the area around the opening.

<2> Vertical excavation (Figure 4) Perform vertical excavation 6 under safe conditions with the upper part reinforced.

As excavation progresses, the surrounding wall surface is temporarily held by earth retaining materials such as liner plates 7.

A backfill material 8 is injected into the space between the liner plate 7 and the wall earth and sand.

The horizontal cross-sectional shape of the vertical shape 6 can be circular, rectangular, or any other shape required at the site.

<E> Concrete work (Figure 5) After completing the excavation of the vertical 6, assemble reinforcing bars and steel frames on the walls and bottom, and then pour concrete 9.

Further, the upper reinforcing material is removed, and concrete 9 is poured from the inside of the horizontal tunnel 1 section to complete the structure as an integrated structure.

〈〈〉How to use it as a branch structure (Fig. 6) New tunnels 10 will be constructed in the future at different heights toward the sides of the underground vertical structure 6 thus constructed.

The branching is completed when the tip of this new tunnel 10 hits the wall surface of the vertical shape 6 constructed by the above method and opens.

<Effects of the Present Invention> Since the method of the present invention completes the branching of several tunnels with different heights through the steps described above, the following effects can be achieved.

(a) This method does not branch directly from a horizontal tunnel, but instead creates a vertical shape underground and branches through this vertical shape.

Therefore, compared to the method of directly branching out on the same narrow plane inside the tunnel, branching work is extremely easy because it does not affect the main pipe in use.

Once the (mouth) branching path is completed, the next step is to branch out the group of tubes in use, and the branching section has various devices attached to it, resulting in an extremely complex structure.

In this case, in the branch structure of the present invention, since a wide space is formed in the vertical direction, many new devices can be added.

Subsequent operation and inspection of such a branching device is also easy.

[Brief explanation of drawings]

Claims (2)

[Claims] (1) A structure that connects one horizontal tunnel built underground to another horizontal tunnel of different height, with a vertical shaft built downward from the bottom of one horizontal tunnel. , The structure of an underground tunnel branch consisting of other tunnels connected through the lower part of this shaft. (2) After improving the ground around the horizontal tunnel built underground, reinforcing the inside of the part of the horizontal shaft where the shaft is planned to be constructed, dismantling the floor members in that part, and protecting the surrounding area in the exposed ground after dismantling. A method of constructing an underground tunnel branch by excavating a shaft and reinforcing the inside of the shaft with concrete.