JPS6346236B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to an expanding shield tunneling machine for widening a portion of a normal diameter tunnel to form an enlarged tunnel.

(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. was common.

However, with this method, there have been problems in recent years, such as it being difficult to secure a place to excavate a vertical hole as above-ground structures have become overcrowded, and it takes time and effort to backfill the vertical hole after the widening work is 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. As shown in Figure 1, this construction method involves excavating a normal-diameter tunnel 1 using a primary shield excavator (not shown), and then excavating an area 2 of the planned expansion area of the tunnel 1.
A starting base 3 is established by partially enlarging and excavating one end of the area, and an expanding shield excavator 4 is assembled and installed at this starting base 3, and the primary segment 5 that has already been installed over the entire area of the planned expansion area 2 is installed. It is characterized in that the expansion shield excavation machine 4 is propelled in the direction of the arrow while being removed one by one to perform expanded excavation, and a secondary segment (not shown) is applied to the inner surface of the widened part to construct an expanded tunnel.

To explain in more detail the expanding shield excavator 4 used in this construction method, it has a cylindrical outer cutting edge 6 having an outer diameter corresponding to the inner diameter of the expanding tunnel, and a cylindrical outer cutting edge 6 that is substantially concentric with the inner edge of the cutting edge 6. and a cylindrical inner cutting edge 7 which is arranged symmetrically and fixed to the outer cutting edge 6. The inner diameter of the inner cutting edge 7 corresponds approximately to the outer diameter of the primary segment 5 surrounding the normal diameter tunnel 2. Therefore, the expansion shield excavator 4 is configured to excavate an annular area around the normal diameter tunnel 2 to widen the tunnel.

Further, when the widened portion is on soft ground, an annular face plate 8 for retaining the crest is provided between the outer and inner cutting edges 6 and 7. The enlarged shield excavator 4 configured in this manner propels excavation by obtaining a reaction force from the secondary segment using a propulsion jack (not shown).

Use of the expansion shield excavation method improves workability and economy, and use of the expansion shield excavator 4 having the face plate 8 allows safe expansion even in soft ground.

(Objective of the Invention) An object of the present invention is to further improve the expansion shield excavator equipped with the face plate for retaining the pile, by reducing the resistance caused by the face plate and by exerting the excavation effect of the face plate, so that it can be used for widening work on soft ground. An object of the present invention is to provide an expanding shield excavator that improves the efficiency and safety of a machine.

(Main Structure of the Invention) The gist of the present invention is to provide an annular crest-holding face plate between the outer and inner cutting edges that are fixed to each other,
This is an enlarged shield excavator in which the face plate is provided with a soil removal window and a bit, and the face plate is rotated in one direction or back and forth in the circumferential direction by driving a jack.

(Embodiment of the Invention) The present invention will be described below based on an embodiment shown in FIGS. 2 to 4. Note that detailed explanations of parts that are the same as those in the prior art will be omitted.

2 to 4, the enlarged shield excavator 10 of the present invention has a cylindrical outer cutting edge 11, and is arranged almost concentrically inside the outer cutting edge 11, as in the previously proposed one. It has a cylindrical inner cutting edge 12 fixed to an outer cutting edge 11.

Further, according to the present invention, the enlarged shield excavator 10 has the outer cutting edge 11 and the inner cutting edge 1.
2, and at least one jack 14 for driving the face plate 13.

The face plate 13, the outer cutting edge 11 and the inner cutting edge 1
A slidable seal member 15 is provided between each of the parts 2 and 2 to prevent the inflow of earth and sand.

In addition, the jack 14 is the face plate 1 in this embodiment.
The face plate 13 is driven in the circumferential direction by obtaining a reaction force from the reaction force receivers 19a and 19b attached to the third side and protruding from several places inside the outer cutting edge 11. For example, first, the tip of the jack 14 is engaged in the contracted state with the reaction force receiver 19a located at the position of the reaction force receiver 19b shown in FIG.
is rotated by a predetermined angle in the direction of the arrow to reach the state shown in FIG. When rotating again, the extended jack 14 is shortened and the next reaction force receiver 19 is moved.
After engaging with a, the jack 14 is extended. Note that the jack 14 is attached to the outer cutting edge 11 or inner cutting edge 12 side, and is used as a reaction force receiver (not shown).
It is also possible to drive the face plate 13 by providing it on the face plate 13 side.

Further, the jacks 14 can be attached in pairs to the face plate 13 at symmetrical positions. Furthermore, when at least one pair of jacks 14 rotates the face plate 13 in one direction, at least another pair of jacks 14 If the base plate 13 is arranged so that the face plate 13 is rotated in the opposite direction, the face plate 13 can be rotated back and forth.

The face plate 13 is provided with an earth-retaining window 1 in order to reduce the propulsion resistance due to earth retaining and facilitate propulsion.
A large number of drilling bits 16 are provided at and around 3a. In addition, the above-mentioned expansion shield excavator 10 is
Secondary segment 17 installed in the enlarged tunnel
(Fig. 4), it is equipped with a propulsion jack 18 that obtains a reaction force and propels the expansion shield tunneling machine.

(Effects of the Invention) As is clear from the above embodiments, in the present invention, the soil retaining face plate 13 provided with the soil removal window 13a and the bit 16 is rotated in one direction in the circumferential direction or It is rotated back and forth, and the excavation effect by the bit 16 and the soil removal window 13a are
The propulsion resistance applied to the face plate 13 is reduced by taking in earth and sand from the ground, and this is particularly effective for excavating in soft ground. In addition, by using a jack as the means for rotating the face plate 13, there is no need for a complicated power transmission mechanism interposed in the middle, unlike when rotating the face plate by a motor, resulting in a simple configuration and a strong rotating force. There is also the advantage that it is easy to obtain.

[Brief explanation of the drawing]

FIG. 1 is a schematic vertical cross-sectional side view showing the previously proposed expansion shield excavation method and the excavation state of the expansion shield excavation machine, FIG. 2 is a schematic front view of the expansion shield excavation machine according to an embodiment of the present invention, and FIG. The figure is an enlarged view of the main part of Figure 2.
FIG. 4 is a sectional view taken along the - line in FIG. 3. DESCRIPTION OF SYMBOLS 10... Enlarged shield tunneling machine, 11... Outer cutting edge, 12... Inner cutting edge, 13... Face plate, 13a...
... Soil removal window, 14 ... Jack, 15 ... Seal member, 16 ... Bit, 17 ... Secondary segment, 18 ... Propulsion jack, 19a, 19b ...
...reaction force received.

Claims (1)

[Claims] 1. A cylindrical outer cutting edge, a cylindrical inner cutting edge that is arranged substantially concentrically inside the outer cutting edge and fixed to the outer cutting edge, and the outer cutting edge and the inner cutting edge. A ring-shaped face plate for retaining the pile, which is interposed between the two and provided with an excavation bit and a window for taking out the soil;
a jack that is interposed between the outer cutting edge side or the inner cutting edge side and the face plate and rotates the face plate in one direction or reciprocates in a circumferential direction relative to the outer cutting edge and the inner cutting edge; An expanding shield excavator characterized by being equipped with.