JPS59177497A - Method of construction of expansion and propulsion - 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] a. Industrial application field - The present invention relates to an expansion propulsion method, which is a type of tunnel excavation method, and in particular, a method used to expand a part of an existing tunnel, This invention relates to a construction method that is both easy to work with and economical.

B. Prior Art Conventionally, as a construction method for enlarging a part of an existing tunnel, there is an expansion shield construction method already proposed in the applicant's previous application. The outline of this enlarged shield construction method will be explained based on FIGS. 1 to 3.

FIG. 1 shows an existing tunnel 1, to which a segment 2.3 as a lining is installed, and reference numeral 4 indicates an area to be expanded. At the excavation start end of the planned expansion area 4, a cut and widening portion 6 is excavated using a desired means as shown in FIG.

At this time, if the ground is soft, a reinforced ground 5 is formed by a known ground improvement method such as chemical injection, and retaining iron plates 8 are installed at predetermined locations on the inner peripheral surface of the cut and widened portion 6. Then, in the cut out part 6, there is an enlarged shield j, t+i
-i27 'ft: Set MFi upright.

This expanding shield excavator 7 has a hood-shaped propelling blade lower a having a cutter spatula l'' with a plurality of cutting blades missing from the outer periphery, and a reaction force from the earth retaining iron plate 8 and the like on the inner periphery of the cutting and spreading portion 6. The glossiness 7b for propelling the propelling blade lower a is 1 no 1 η.

FIG. 3 shows the excavation state of the enlarged shield excavator 7,
The expanding shield excavator 7 is propelled while removing the existing segments 2 one by one using an erector (not shown).

And the expansion shield excavator 7's i? (The forward and reaction force is applied to the newly installed segment 3 in the expanded tunnel.
The gloss is obtained by the abutment of the gloss 7b. Further, reference numeral 11 indicates a rail for an erector one-bogie for removing the existing segment 2, and reference numeral 12 indicates a rail for an erector one-bogie for attaching the segment 3 to the enlarged tunnel. After the excavation is completed, the expansion shield excavator 7 is disassembled and necessary parts are removed and reused.

According to the above-mentioned expansion shield construction method, there is no need to excavate or backfill a shaft, and installation of an expansion shield excavator 7 is not necessary.
! /l! Since the structure is easy to construct, and it is easy to obtain a propulsion reaction force, the tunnel expansion work is extremely efficient compared to conventional construction methods, and construction costs can be significantly reduced.

However, in the case of the above-mentioned enlarged shield method, since the propulsion gloss 7b is installed in the propulsion blade lower a of the enlarged 7-first excavator 7, part of the excavation cross section is removed by the jack 7 during excavation.
b will be blocked, and there is a risk that the excavation force will be reduced. In addition, hydraulic piping and hydraulic hoses are connected to the gloss 7b, and these are extended as the expanding shield excavator 7 excavates, so there is a problem that they become a hindrance to the workers and impair workability. Moreover, especially when the existing tunnel 1 is used for passing various cables, etc.

If the above-mentioned expansion shield excavation 7 is applied to a tunnel having a small diameter or a short length of the expansion tunnel part, there is a risk that it will become uneconomical VC.

C. Object of the Invention The present invention has been made in view of the problems of the conventional art, and is designed to prevent the excavation force from being impaired, and especially for small-scale enlarged tunnels. The purpose is to provide an economical expansion propulsion method when cutting.

d.Structure of the Invention The gist of the present invention is to set the propulsion blade opening of an expanding shield excavator in the cut and widened part of an existing tunnel, and to
The purpose is to make the excavation proceed with a former pusher jack that is separated from the propelling blade opening and installed behind the propelling blade opening. In this case, expanding tunnel segments are successively interposed between the propulsion blade opening of the excavator and the original pusher, and the original pusher presses the propulsion blade via these segments. There are two ways in which the moto pusher presses the propelling blade opening. One is when the former pusher presses the propelling blade opening or segment through the pusher 4-, and the other is when the former pusher presses the propelling blade opening or segment directly. This is the case.

Embodiment C of the Invention The present invention will be fully described below based on Embodiment R shown in FIGS. 4 to 11. The same reference numerals will be used to refer to the same parts as in the prior art.

4 to 7 show a first embodiment of the present invention. According to the present invention, first, an area 4 to be expanded in the middle of an existing tunnel 1 is cut 7, and its ends are widened and excavated in a desired manner. Then, the lower propulsion blade a of the expansion shield excavator 7 for excavating the outer periphery of the existing tunnel 1 is assembled and installed in the cutting and widening portion 6, and the lower propulsion blade a is separated from the lower propulsion blade a. Motoshi Jatsuki who promotes 1:3
t#itM Fix to the reaction force receiver 14 etc. in the existing tunnel 1 behind the blade lower a. In this embodiment, the original push jack 13
is configured to press the advancing blade lower a via a cone-shaped push ring 15 fixed thereto.

As shown in FIGS. 4 to 6, the cone-shaped press ring 15 is made of a large number of frame members 15a, etc., and has a structure in which the small diameter portion J5b is fixed to the tip of a large number of original press gloss 13. .

After inserting the propelling blade lower a and the main pusher jack 13 as shown in the two sets, as shown in Fig. 7, the segment 2, which is the lining of the existing tunnel 1, is moved by an erector (not shown). The lower propulsion blade a is made to dig along the existing tunnel 1 while being removed one by one. After the propelling blade lower a first propels one stroke of the moto-pushing jack, the propelling blade lower a and the pushing ring 1
Segments 3 for enlarged tunnels are successively interposed between the two segments 3 and 5, and the lower propulsion blade a'f: excavates together with the segments 3 through these segments 3.

After the excavation is completed, usually the segment 3 is left as a lining and the enlarged tunnel 4 is constructed.

''As is clear from the description of the two sets of embodiments, in the present invention, only the propelling blade lower a digs until the tip of the main pusher jack 13 is left behind the propelling blade 117a.
3 does not interfere with excavation, and hydraulic hoses and the like do not get in the way, which has the advantage of improving workability. Also,
Since there is no need to use a conventional erector to attach segment 3 to the enlarged tunnel, the work becomes easier, and even if the enlarged tunnel is small-scale, it can be applied as is, making it easy to install the segment 3 on the enlarged tunnel. The effect of economical excavation can be obtained.

8 to 11 show a second embodiment of the present invention, in which a cone-shaped push ring 15 is used as a reaction force receiver for the original pusher 13, and its small diameter portion 15b is attached to the end of the segment 2 of the existing tunnel 1. It is fixed to the part. A large number of original push jacks 13 are fixed to a push ring 15 which is a reaction force receiver.

In this embodiment, as shown in FIG. 11, the main pusher jack 13 directly pushes the propelling blade lower a or the interposed segments 3 in sequence.

In this embodiment as well, since the original pusher jack 13 remains at a fixed position, the same effects as in the first embodiment can be obtained.

f As described above in detail, according to the method of the present invention, the following effects can be obtained.

That is, since only the propulsion blade of the enlarged seven-fold excavator is used, the structure of the excavator is simplified and the weight is reduced.

Furthermore, since there are no hydraulic hoses or other members in the excavated area, work efficiency is improved.

Since enlarged tunnel segments can always be added and assembled in the same position, there is no need to move the erector.

The push ring or reaction force receiver combined with the original push jack,
It can be effectively used as a scaffold for assembling segments for enlarged tunnels.

Since it uses a moto-puzutsuyasoki, which is different from a mobile glossy, the hydraulic pump unit etc. are stationary and do not get in the way of work.

In particular, since there is no need to move the erector, it is possible to economically excavate small-scale enlarged tunnels.

Furthermore, the setup required for main excavation, which is required with the expanded shield method, is not required. In other words, in the present invention, an example has been shown in which an existing tunnel is constructed using the shield method and lined with its segments, but an existing tunnel constructed using the propulsion method or other construction methods, such as concrete or a hollow pipe, etc., has been shown. It can also be applied to various existing tunnels that have been lined.

[Brief explanation of the drawing]

Figures 1 to 3 are cross-sectional explanatory diagrams showing the previously proposed expansion shield construction method, Figure 4 is a cross-sectional explanatory diagram showing the first embodiment of the method of the present invention, and Figure 5 is ■-v of Figure 4. Figure 6 is a thin cross-sectional view of νI-Vl in Figure 4, Figure 7 is an explanatory diagram showing the state of excavation of the propelling blade in Figure 4, and Figure 8 is the second cross-sectional view of the method of the present invention.
A cross-sectional explanatory diagram showing the embodiment, FIG. 9 is IX-IX in FIG.
A line sectional view, FIG. 10 is an x'-xffM sectional view of FIG. 8,
Figure 1 1'1 is an explanatory view showing the state of digging of the propelling blade opening in Figure 8. [Explanation of symbols] 1... Existing tunnel 2.3... Segment 4
... Expansion planned area (expansion tunnel) 6... Cut and widen section 7a River propulsion blade ro 13...
Original push jack 14... Reaction force receiver 15... Push ring (reaction force receiver) - Patent applicant Mitsui Construction Co., Ltd. Figure 1 Figure 2 Figure 0 Figure 3 Figure 4 aN 1/- 7fu Cσ//

Claims (3)

[Claims] (1) Excavation will be carried out at one end of the planned expansion area in the middle of the existing tunnel, and the propulsion blade of the expansion shield machine that excavates the outer periphery of the existing tunnel will be installed in the cut and widened part. , a former push jack that is separated from the propulsion blade opening and used to propel the propulsion blade opening is installed behind the propulsion blade opening, and the existing tunnel lining is sequentially removed, and the propelling blade opening and the original An expansion propulsion construction method characterized by constructing an enlarged portion in the existing tunnel by propelling the propulsion blade along the existing tunnel by the original pusher jack while sequentially interposing segments ffi for the enlarged tunnel between the pusher jack and the pusher jack. (2) The former pusher presses the propulsion blade opening or enlarged tunnel segment via a push ring f:
A method according to claim 1, characterized in: (3) The method according to claim 1, characterized in that said original pusher directly presses said propulsion cutting edge or enlarged tunnel segment.