JPS6134556B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a construction method in which the cross-sectional shape of a tunnel lined with segments is widened in parallel with tunnel excavation.

Typically, tunnels constructed using the shield method are used for sewerage systems, power and communication wiring pits, subways, and the like.

Such tunnels are formed by excavating earth and sand using the shield method and lining the excavated walls with concrete or steel segments. , or when a cross-sectional area wider than the tunnel cross-section is required, such as for wiring, connections, and areas for maintenance of waste water, the conventional shield construction method involves excavating a vertical shaft from the ground after excavating the tunnel. Normally, the necessary widening section is constructed.

However, in recent years, it has become extremely difficult to acquire land and construct the shafts as described above due to deteriorating road conditions, absolute land shortages, and growing local residents' interest in environmental conservation.

The present invention was developed in view of these problems, and provides a tunnel widening method that allows a tunnel to be excavated using a shield machine and a desired widening section to be simultaneously constructed without excavating a vertical shaft from the ground. It is.

Embodiments of the present invention will be explained with reference to the drawings: 1
is a shield machine, and as is known, the cutter head excavates the ground 2, and a propulsion jack 3 installed inside the shield machine uses a segment ring 4 assembled inside the rear end of the shield machine as a reaction wall. It is propelled forward and excavates a tunnel 6 having approximately the same cross section as the shield machine.

Reference numeral 5 denotes a planned widening section that widens the cross-sectional shape of the tunnel 6 and extends a certain length in the direction of propulsion of the shield machine 1.

The segment ring 4 lines the inner peripheral wall surface of the tunnel 6 formed by excavating the ground with the shield machine 1, and consists of 1 to 2 ring segments connected to the rear end of the shield machine 1. ring 7
Following this segment ring 7, a number ring is formed by combining a generally used tunnel forming segment 9 with a steel plate widening wall forming segment 8 which is incorporated into the section where the cross-sectional shape of the tunnel is to be widened. It consists of a segment ring 10, and a rear segment ring 11 that is connected to the segment ring 10 and assembled from the shaft to the starting end of the planned widening section 5.

As shown in FIG. 6 (view from inside the tunnel), the widening wall forming segment 8 includes upper and lower side plates 8a, 8b and left and right side plates 8c, which are parallel to each other and have the same width.
The peripheral edge of a wall plate 8d provided on the ground side surface is integrally connected to one end of the peripheral wall frame 8', and the wall plate 8d is formed on a rectangular peripheral wall frame 8' consisting of As shown in Fig. 7, mortar 12 with a poor mix and having the same strength as the ground is pasted on the surface of 8d on the ground side, which is formed into an arcuate surface according to the shape of excavation by the shield machine. be. Furthermore, a flange plate 8e having an appropriate width is integrally provided around the other end of the peripheral wall frame 8' facing inward.

Reference numeral 13 designates an earth and sand intake port provided in the wall plate 8d of this widening wall forming segment 8. In the figure, there are two rectangular openings at the top and bottom, and a cover plate is attached to the opening by a rotating hinge 14. 15 is attached so that it can be opened and closed freely, and the opening is closed during tunnel construction.

Reference numerals 16 and 17 denote a plurality of bolt holes drilled at predetermined intervals in the circumferential direction on the upper and lower, left and right sides 8a, 8b, and 8c of the peripheral wall frame 8', respectively.
The bolt holes 16 provided in the upper and lower side plates 8a and 8b are
8b adjacent to the segment 9 in the circumferential direction of the tunnel,
9, and the left and right side plates 8c, 8c
The bolt holes 17 provided in the tunnel connect the side plate 8c to the segment 9 or the widening wall forming segment 8 adjacent in the longitudinal direction of the tunnel.

Note that one side of the segment 9 adjacent to the side plate 8c is formed so that the side plate 8c and the bolt holes are aligned.

Reference numeral 18 denotes bolt holes drilled at regular intervals in the flange plate 8e of the peripheral wall frame 8'.

19 is a peripheral wall frame 8' of the widening wall forming segment 8;
As shown in FIGS. 8 and 9, a flange plate 19 having the same shape as the flange plate 8e of the segment 8 is provided at both opening edges.
The flange plate 19a is provided with a plurality of bolt holes 20 that engage with the bolt holes 18 provided in the flange plate 8e of the segment 8.

21 is Jack, as shown in Figures 4 and 5,
A plurality of cylinders 21 are arranged perpendicularly to the tunnel on the top, bottom, left and right on a cart 23 that moves on rails 22, 22 laid in the length direction of the tunnel. It is fixed to a frame 24 erected on one side, and the end of the rod 25 is brought into contact with the flange plate 19a of the short cylindrical body 19.

Reference numeral 26 denotes a reaction force receiver that comes into contact with the inner circumferential surface of the segment 9 to receive the reaction force of the action of the jack 21, and an adjustment journal jack 27 is interposed between it and the frame 24.

Now, in the process of assembling the segments 9 while excavating the ground 2 with the shield machine 1 and forming a tunnel with the segment rings 4, the rear end of the shield machine 1 is at the starting end position of the planned widening section 5. When assembling segments in that part when the tunnel is reached, use the widening wall forming segment 8 in the part where the tunnel is to be widened, and connect the bolt hole with the normal segment 9 adjacent above and below it using a connecting bolt (not shown). Segment rings 1 are joined to each other through
0, and the rear end of this segment ring 10 is similarly joined to the front end of the existing rear segment ring 11 with a connecting bolt. Then,
As the shield machine excavates, several rings of segment rings 10 having widening wall forming segments 8 are assembled in succession, and then one front segment ring 7 similar to the rear segment ring 11 is assembled.
~Assemble 3 rings.

The frontmost ring of this segment ring 7 is located inside the rear end of the shield machine 1, and its outer circumferential surface is in sliding contact with the tail packing 28 attached to the tail part of the shield machine 1 to prevent groundwater etc. from flowing into the tunnel. is prevented.

After the segment rings 7 of the front part and the part where the width is to be formed are assembled in this way, the propulsion of the shield machine 1 is temporarily stopped. Next, the cart 23 is moved and stopped at the position of the widening wall forming segment 8,
The journal jack 27 is adjusted to bring the reaction force receiver 26 into contact with the segment 9 opposite to this segment 8. Furthermore, a short cylindrical body 1 is attached to the back side of the segment 8.
9 is arranged, and the bolt hole 2 of the flange plate 19a is
0 and bolt hole 1 of flange plate 8e of segment 8
8 and then connect them with bolts, operate the jack 21 and attach the rod 25 to the short cylindrical body 19.
is brought into contact with the back side flange plate 19a of.

Next, the peripheral wall frame 8' of the widening wall forming segment 8
Remove the connecting bolts between the segment 8 and other segments, open the lid 15 of the segment 8 to open the earth and sand intake port 13, remove the poorly mixed mortar 12 through the intake port 13, excavate the ground, and at the same time open the jack 21. It is activated to press the widening wall forming segment 8 integrated with the short cylinder 19 and propel it into the ground as excavation progresses.

In this case, if the soil on the ground is soft, the segment 8 can be propelled while the soil flows into the tunnel from the soil intake port 13 only by the pressing force of the jack 21; if the soil is hard, the segment 8 can be propelled by manual input. Excavate by digging or using appropriate excavating equipment.

In this way, the segment 8 is propelled into the ground, and when the back surface of the short cylindrical body 19 connected to the segment 8 reaches the inner peripheral surface of the segment 9, the propulsion is stopped, the lid 15 is closed, and the short cylindrical body 19 and the segment 9
and the like with bolts, retract the rod 25 of the jack 21, connect the next short cylindrical body 19 to the back of the propelled short cylindrical body 19, release the fixation with the segment 9, and operate the jack 21 again. The short cylindrical body 19 is propelled into the ground together with the widening wall forming segment 8, and this operation is repeated to separate the widening wall forming segment 8 and the plurality of short cylindrical bodies 19 incorporated into one segment ring 10. An expanded portion 29 having a desired width is formed by this.

Further, the formation of such widening portions 29 is performed by forming widening wall forming segments 8 of each segment ring 10.
As shown in FIGS. 10 and 11, a widened tunnel starting end 30 having a widened portion 29 several ring widths long in the tunnel direction is formed.

It goes without saying that waterproof packing may be applied between the normal segment 9 and the widening wall forming segment 8 or the short cylindrical body 19.

Next, the joint between the tunnel 6 and the widened tunnel starting end 30 is reinforced as appropriate, and the other short cylindrical bodies 19 are brought into contact with each other while leaving the front and rear end walls 31 and 32 of the widened tunnel starting end 30 in the tunnel direction. The partition wall 33 formed in this manner is removed.

Also, the connection between the rear end segment 9 of the widening section and the front end segment 9 of the rear segment ring 11 is released, and the rear end wall 32 of the widening tunnel starting end section 30 is disconnected.
The widening wall forming segment 8 and the short cylindrical body 19 that are in contact with the periphery of the tube are separated by cutting or other means. At the same time, an inner segment 35 that is in contact with the rear end inner circumferential surfaces of the normal segment 9 forming the widening tunnel starting end 30, the widening wall forming segment 8, and the short cylindrical body 19 through a packing 34 are assembled, and the rear end surface of the inner segment 35 in the tunnel direction, the rear end wall 32, and the front end segment 9 of the rear segment ring 11 are appropriately watertightly joined. Furthermore, as shown in FIG.
A plurality of cylinders 37 are fixed to the front segment 9 and the short cylinder 19 via brackets 36, and the ends of the rods 38 are brought into contact with the front end surface of the inner segment 35.

Furthermore, the front end wall 31 of the widening tunnel starting end 30
An excavation opening 39 is opened in the opening 39, and an opening/closing cover plate 40 is attached to the opening 39 to prevent the inflow of earth and sand.

In this way, after forming the widening tunnel starting end 30, arranging the cylinder 37 there, and forming the opening 39, the shield machine 1 is operated again to excavate the ground 2 and excavate. The shield machine 1 is advanced by the jack 3, and excavation by the shield machine 1 is stopped with the rod of the propulsion jack 3 extended.

Next, the cover plate 40 of the widening tunnel starting end 30 is opened and the ground is excavated through the excavation opening 39. At the same time, the inner segment 35 is used as a reaction force receiver to extend the rods of the cylinders 37, 37...37, and the tunnel width is widened. The segment 9 forming the tunnel starting end 30, the widening wall forming segment 8, and the short cylindrical body 19 are integrally pushed forward to widen the width as the excavation progresses.The tunnel starting end 30 is extended in the shield advancing direction to widen the width. A tunnel 41 is formed. At this time, cylinder 3
Width tunnel starting end 30 due to extension of rod 7
The rod of the propulsion jack 3 of the shield machine 1 is contracted in accordance with the advance of the shield machine 1.

In this way, when the rod 38 of the cylinder 37 forming the widened tunnel section 41 is extended to the maximum extent, excavation from the opening 39 is stopped, the cover plate 40 is closed to prevent the inflow of earth and sand, and the rod 38 is retracted. Then, a new inner segment 35 is assembled between the rod end and the existing inner segment 35.

After that, the newly installed inner segment 3
5, the rod end of the cylinder 37 is brought into contact with the front end surface of the cylinder 37,
After receiving the shield, the shield machine 1 excavates again, and then the cylinder 3 is extended.
This operation is repeated to extend the widened tunnel portion 41 as shown in FIG. 14.

When construction of the entire length of the widened tunnel section 41 planned in this way is completed, the shield machine 1 excavates and performs normal shield excavation in which segment rings are assembled in the shield machine to complete the prescribed tunnel. It is.

Incidentally, backfilling of mortar or the like is performed in the gap 42 between the outer circumferential surface of the inner segment 35 forming the wide tunnel portion 41 and the ground 2 by a conventional method.

As described above, the present invention expands the tunnel by propelling a part of the segment ring following the shield machine in a direction perpendicular to the length direction of the tunnel, and then expands the segment to form the expanded cross section of the tunnel. After assembling the inner segment on the inner surface, the shield machine is excavated to a predetermined length, and the segment for forming the cross section of the widened tunnel is excavated in front of the widened part in the tunnel length direction while using the inner segment as a reaction force receiver. This method involves repeating the process of advancing the tunnel to form a tunnel with a long widening section in the longitudinal direction of the tunnel, so there is no need to excavate a vertical shaft from the ground. A desired widening portion can be formed within the tunnel to a desired length, and therefore,
This system can completely solve problems such as acquiring land for shafts, and can also form tunnels of arbitrary length without being limited by the length in the tunnel direction. The width can be obtained continuously, and compared to the case where the width is expanded separately, it is possible to improve the efficiency of excavation work, centralize the transportation of earth and sand, and shorten the construction period by a large amount.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a simplified vertical sectional side view showing the state before the formation of the widened tunnel section, and FIGS. 2 and 3 are taken along lines A-A and B in FIG. 1, respectively.
- An enlarged sectional view taken along line B; FIG. 4 is an enlarged sectional view showing the state of the widening wall forming segment before it is propelled;
Fig. 5 is an enlarged cross-sectional view during propulsion, Fig. 6 is a rear view of the widening wall forming segment, Fig. 7 is a central vertical cross-sectional view thereof, Fig. 8 is a front view of the short cylinder, and Fig. 9 10 is a simplified longitudinal sectional side view showing the formation state of the starting end of the widened tunnel, FIG. 11 is a sectional view taken along line C-C in FIG. 13 is a sectional view taken along the line D-D in FIG. 12, FIG. 14 is a simplified longitudinal side view showing the enlarged tunnel section being extended, and FIG. 15 is a sectional view taken along the line D-D in FIG. 12. - It is a sectional view taken on the E line. 1... Shield machine, 2... Ground, 3... Propulsion jack, 4, 7, 10, 11... Segment ring, 5... Planned widening section, 6... Tunnel,
8... Segment for widening formation, 19... Short cylindrical body,
21... jack, 30... widening tunnel starting end, 35... inner segment, 37... cylinder, 41... widening tunnel.

Claims (1)

[Claims] 1. After widening the tunnel by propelling a part of the segment ring following the shield machine in a direction perpendicular to the length direction of the tunnel, assembling an inner segment on the inner surface of the segment forming the widened tunnel cross section, Thereafter, the work of making the shield machine dig a predetermined length, and the work of advancing the widening tunnel cross-section forming segment using the inner segment as a reaction force receiver while excavating the front part of the widening part in the tunnel length direction are repeated. A method for constructing an expanded tunnel, characterized by forming a tunnel having an expanded portion that is long in the length direction of the tunnel.