JPS6030797A - Enlarging shield construction method - 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 (Technical Field of the Invention) The present invention relates to an expansion/fold construction method in which a part of a normal diameter tunnel is expanded into an enlarged tunnel. This invention relates to an expansion shield construction method that allows for immediate excavation of an expansion tunnel without the hassle of.

(Prior art) Conventionally, in order to enlarge a part of a normal diameter tunnel, a vertical hole is excavated from the ground in the area planned for expansion, and various excavating machines are introduced through the vertical hole to widen the normal diameter tunnel. It was common to do so.

However, with this method, it is difficult to secure a place to excavate a vertical hole as above-ground structures have become overcrowded in recent years.
There were problems such as the time-consuming work required to backfill the vertical hole after the Ushita widening work was completed.

Therefore, in a previous application, the present applicant proposed a method for excavating an enlarged tunnel that eliminates the need to excavate a vertical hole. This construction method involves excavating a normal-diameter tunnel with a secondary shield excavator, then partially enlarging and excavating one end of the area scheduled for expansion of the tunnel to provide a starting base for the enlarged shield excavator.
- The expansion shield excavator will be assembled and installed at this starting base, and the expansion excavation will be carried out by propelling the expansion shield excavator while sequentially removing segments of the normal diameter tunnel that have already been installed throughout the area scheduled for expansion. At the same time, a new segment is added to the inner surface of the widened portion to construct an enlarged tunnel.

According to this previously proposed construction method, the workability and economic efficiency are improved, and it is possible to shorten the construction period and reduce costs.

However, when the enlarged section extends over a long distance, it is desirable to avoid duplication of the time and effort required to construct a normal-diameter tunnel and the time and effort required to construct an enlarged tunnel.

(Objective of the Invention) Therefore, the present invention aims to provide an expansion shield construction method that can eliminate the trouble of constructing a normal diameter tunnel in areas scheduled for expansion among normal diameter tunnels and can immediately excavate an expanded tunnel. Particularly, an object of the present invention is to provide an enlarged shield construction method that can excavate a normal diameter tunnel and an enlarged tunnel by using a cutter in combination.

(Main Components of the Invention) The gist of the present invention is to excavate a normal diameter tunnel using a partially shielded stationary machine equipped with a cutter on the front surface having an outer diameter corresponding to the inner diameter of the normal diameter tunnel. After reaching the planned expansion area, behind the above-mentioned next shield excavator,
An enlarged part is provided as a starting base for the enlarged shield excavator, and the enlarged shield excavator is assembled in the enlarged part and connected to the next shield excavator, and the outer diameter of the cutter is the outer diameter of the enlarged shield excavator. The present invention is to add an extension to the cutter so as to substantially match the cutter, and to excavate the enlarged tunnel by simultaneously propelling the 7-rd tunnel excavator and the enlarged seal tunnel excavator.

(Example of the invention) The present invention will be described below based on embodiments shown in the drawings.

According to the construction method of the present invention, first, as shown in Figs. 1 and 2, a normal diameter tunnel 2 is excavated with a partial shield excavator 1 having the same structure as the conventional one at one end of the area 3 to be expanded. On the inner surface of 2, a second segment 4 is applied using an existing erector (not shown).

In this case, according to the invention, - the next shield excavator 1 - the cutter 5 with an outer diameter corresponding to the inner diameter of the normal diameter tunnel 2;
In addition, as in the conventional case, there is a nozzle 6 that supplies drilling mud to the cutter 5 side, a nozzle 7 that collects used mud water, and a nozzle 7 that receives a reaction force from the above-mentioned next segment 4 to partially excavate the nord. It is equipped with a jack 8 that propels the aircraft 1.

Next, the above-mentioned “next shield tunneling machine” is installed in the expansion planned area 3.
When this point is reached, further excavation of the normal diameter tunnel 2 is stopped, and an enlarged portion 2a is provided in the normal diameter tunnel 2 behind the -next shield excavator 1, which serves as a starting base for the enlarged shield excavator 9. Various methods are used to form this enlarged portion 2a, such as manual digging, the circumferential enlargement shield method proposed by the applicant, etc.
Generally, an appropriate coating 10 is applied to the inner surface of the enlarged portion 2a.

Next, the blade mouth portion 9a of the enlarged shield excavator 9 is assembled within the enlarged portion 2a. Behind the expansion shield excavator 9,
For example, a reaction force receiver Jl is provided between some segments 4 of the normal diameter tunnel 2, and a desired number of jacks 2 are installed to obtain reaction force from the reaction force receiver 11 and propel the expanding shield excavator 9 to a certain extent. . After that, as shown in FIGS. 3 and 4, the front part of the covering 10 is removed, and the blade part 9a of the enlarged shield tunneling machine 9 is pushed out from the enlarged part 2a by using the jack J2, and then the enlarged part 2a, assemble the intermediate body portion 9b, and connect this to the rear part of the blade mouth portion 9a. The tail portion 9c (FIG. 5) is also assembled in the same manner.

After the expanding shield tunneling machine 9 is completely assembled in this manner, the expanding shield tunneling machine 9 is advanced to a position partially outside the shield "Hoshin Machine" and the two are joined together.

While the above-mentioned shield tunneling machine 1 was stopped,
As shown in FIGS. 7 and 8, an extension 5 is attached to the periphery of the cutter 5.
a is added to make the outer diameter of the cutter 5 almost match the outer diameter of the enlarged shield excavator 9.

1)-1 A new secondary segment 3 is attached to the wall of the previously excavated expansion tunnel 3a where the expanded shield excavator 9 reaches the shield excavator.

1, in this example, the jack 8 of the primary shield excavator 1
is from the outer coating 10 and the secondary segment 1:3) y-
In order to obtain power and simultaneously propel the -next and expanded shield excavator 1.9, remove the tail part of the tii advance machine 1 from the -next shield, provide an extension part 8a at the rear of the jack 8,
The extension portion 8a is adapted to abut against the secondary segment ]3.

However, as shown in FIG. 9, a structure may be adopted in which the expansion shield and the propulsion jack 1/I on the rocky shore 9 side propel both the 71-rudo digging machines 1.9.

As described above, the expansion tunnel is excavated in the area to be expanded using the expansion shield excavation machine 9 integrated with the next shield excavation machine 1. Therefore, it is not necessary to excavate the planned expansion area 3 in advance with the primary shield excavator 1 and then carry out the expansion excavation again while removing the -next segment.

After completing the excavation of the enlarged tunnel of the specified length,
- Separate the cutter added from the next shield excavator 1 and the enlarged shield excavator 9, and excavate a normal diameter tunnel again with the next 7-rd shield excavator 1. According to the present invention, there is no need to dig a vertical hole from the ground during tunnel expansion work, and there is no need to excavate a normal diameter tunnel in advance in the area where the expansion is planned.
It is possible to directly excavate an enlarged tunnel, which has the advantage of improving construction efficiency and being economical.

[Brief explanation of the drawing]

FIGS. 1 to 8 are schematic vertical cross-sectional side views showing each step of the expanding shield construction method in one embodiment of the present invention;
The figure is an explanatory diagram mainly showing a state in which a normal diameter tunnel has been excavated, Fig. 2 is a half cross section taken along the n-Lr line in Fig. 1, and Fig. 3 is an explanatory diagram mainly showing an assembled state of the expansion shield excavator. , FIG. 4 is a half cross-sectional view taken along the I\r −+v line in FIG. Vl −
A half-sectional view taken along the line VII, No. 71 C1 is an explanatory diagram showing the state of excavation of the enlarged tunnel, and FIG. 8 is the vm-vm of FIG. 7.
FIG. 9 is a schematic longitudinal cross-sectional side view showing how an enlarged tunnel is excavated by another actual MQ example of the present invention. 1.-Next shield tunneling machine 2..Normal diameter tunnel 3.
・Planned expansion area 3a... Expansion gear, 4.-Primary segment 5..Cutter 5a-extension part 8.Propulsion jack

Claims (1)

[Claims] The normal diameter tunnel is excavated using a partial shield excavator equipped with a cutter on the front side having an outer diameter corresponding to the inner diameter of the normal diameter tunnel, and when the area where the tunnel is planned to be expanded is reached, the above-mentioned next shield excavator An enlarged part is provided at the rear of the cutter to serve as a starting base for the enlarged shield excavator, and the enlarged shield excavator is assembled in the enlarged part and connected to the next Nord excavator, and the outer diameter of the cutter is set to the enlarged part. )゛tJ:! Add an extension part to the cutter so that it almost matches the outer diameter of the advancing machine, and cover or enlarge the enlarged part using at least one of the propulsion jacks of the secondary shield excavator and the expansion shield excavator. An expansion shield construction method characterized in that the secondary shield excavation machine and the expansion shield excavation machine are simultaneously propelled to excavate an enlarged tunnel by obtaining a reaction force from the segments applied to the tunnel.