JP4563331B2 - Tunnel variable section construction method and tunnel excavator used in the construction method - Google Patents

Description

  The present invention relates to a tunnel variable section construction method for partially reducing the width of a tunnel and a tunnel excavator used in the construction method.

  When constructing road tunnels and railway tunnels, it is necessary to change the cross-sectional shape of the shield mine at locations where tunnels are separated or where structures are to be built later. As a shield method that changes the tunnel cross-section without the need to construct a vertical shaft or an auxiliary method from the ground, a method of widening the tunnel cross-section and a method / equipment for constructing a temporary partition inside the tunnel have been used. Various proposals have been made.

  In recent years, Patent Document 1 proposes a tunnel cross-section changing method and a tunnel excavator that can reduce the cross-section of a shield mine to an arbitrary shape at an arbitrary position using an existing shield machine. .

  According to Patent Document 1, first, a reaction force receiver is installed on the normal cross-section segment at the tunnel cross-section width reduction start position, then a new extension skin plate is fixed inside the skin plate of the shield machine, and an extension shield jack is added. To do. Next, after providing a water-impervious unit between the skin plate and the additional skin plate, the additional shield jack is expanded and contracted while taking the reaction force with the reaction force receiver, and a new section segment is installed. Then, after the tunnel cross-section is reduced, the water-blocking unit is provided after the new cross-section segment and the additional skin plate are joined. Next, after removing the additional shield jack, the shield jack is expanded and contracted while taking the reaction force with the water shielding unit, and the normal section segment is installed.

JP 2004-169396 A

  The present invention effectively uses a water-blocking partition unit and a tail seal device in place of the additional skin plate disclosed in Patent Document 1, sufficiently securing water-stopping properties between the natural ground and the tunnel interior, and easily tunneling It is an object of the present invention to provide a tunnel variable section construction method capable of changing a part of the cross section to a reduced width and the like, and a tunnel excavator used in the construction method.

The tunnel variable cross-section construction method according to the present invention for achieving such an object,
Assembling a new section bulkhead segment having a function of a countersink and a counterplate in succession to the existing normal section segment when the excavator body reaches the tunnel new section start position;
Installing a water-blocking partition wall unit having a size corresponding to a cross-sectional portion that has been continuously dug into the new section partition wall segment;
Attaching a tail seal device to the inner surface of the impermeable partition unit and the rear end of the excavator body corresponding to the impermeable partition unit;
Assembling a new cross-sectional segment in the impermeable partition unit;
Coupling the water barrier unit to an excavator body;
Sequentially assembling the new cross-sectional segments for a predetermined number of rings;
When the excavator body reaches the final position of the new cross section of the tunnel, the step of coupling the impermeable bulkhead unit to the final new cross section segment while uncoupling the excavator body;
Assembling a normal cross-sectional segment in succession to the impermeable partition unit and the final new cross-sectional segment;
Coupling the normal cross-sectional segment to the water barrier unit and the final new cross-sectional segment;
Are performed sequentially,
After the step of assembling the new cross section segment in the water barrier partition unit, another water barrier partition unit is installed, the water barrier partition unit is combined with the existing water barrier partition unit, and the existing water barrier partition unit is installed. Instead of connecting to the excavator body,
Further, prior to the installation of the second-stage impermeable partition unit, a water-stop slide plate mounted on the existing impermeable partition unit is overhanged, and its tip abuts against the outer surface of the corner of the new section segment. The gap between the opposing surfaces of the impermeable partition unit and the new cross-sectional segment is sealed .

  Further, in the step of installing the water barrier partition unit, the water barrier partition unit is temporarily coupled to the new sectional partition segment.

In order to achieve such an object, a tunnel excavator according to the present invention includes:
A tunnel excavator used when performing the tunnel variable section construction method,
An excavator body having a main propulsion jack that takes a reaction force on an existing normal cross-section segment and a sub-propulsion jack that takes a reaction force on an existing new cross-section segment, and a tail seal device at the rear end of the skin plate;
When changing from a normal cross-section tunnel to a new cross-section tunnel, it is installed at the rear end of the skin plate, and has a water-impervious partition unit equipped with a tail seal device on its inner peripheral surface,
Have
The impermeable partition unit is formed to have a size to fill a cross-sectional portion that has been changed to a dug by changing the tunnel,
In addition to the tail seal device attached to the rear end of the skin plate, a tail seal device newly attached is provided near the rear end of the skin plate corresponding to the water-impervious partition unit. .

In order to achieve such an object, a tunnel excavator according to the present invention includes:
An excavator body having a main propulsion jack that takes a reaction force on an existing normal cross-section segment and a sub-propulsion jack that takes a reaction force on an existing new cross-section segment, and a tail seal device at the rear end of the skin plate;
When changing from a normal cross-section tunnel to a new cross-section tunnel, it is installed at the rear end of the skin plate, and has a water-impervious partition unit equipped with a tail seal device on its inner peripheral surface,
Have
The impermeable partition unit is formed to have a size to fill a cross-sectional portion that has been changed to a dug by changing the tunnel,
Near the rear end of the skin plate corresponding to the water-impervious partition unit, a tail seal device newly attached in addition to the tail seal device attached to the rear end portion of the skin plate ,
Furthermore, the water-impervious partition unit is provided in a plurality of stages in the tunnel excavation direction .

  According to the present invention, a water-blocking partition unit with a tail seal device, which is sized to fill a cross-sectional portion that has become an overexcavated portion, is attached to the rear end portion of the excavator body, and the tail seal device of the water-blocking partition unit is used. A tail seal device was also installed near the rear end of the excavator body in a continuous manner, and this water-impervious partition unit was brought into sliding contact with the newly assembled segments that were sequentially assembled during excavation. By cooperating with the tail seal device attached to the rear end, it is possible to easily change a part of the tunnel cross-section while reducing the width of the tunnel while ensuring sufficient water-stopping.

  Hereinafter, a tunnel variable section construction method according to the present invention and a tunnel excavator used in the construction method will be described in detail with reference to the accompanying drawings.

  1 is a rear view of a tunnel excavator showing an embodiment of the present invention, FIG. 2 is a process diagram of a tunnel variable section construction method using the tunnel excavator of FIG. 1, and FIG. 3 is a tunnel variable by the tunnel excavator of FIG. 4 is a process diagram of the tunnel variable cross-section construction method using the tunnel excavator of FIG. 1, FIG. 5 is a process diagram of the tunnel variable cross-section construction method of the tunnel excavator of FIG. 1, and FIG. 3 is a sectional view taken along the line BB in FIG. 3, FIG. 7 is a sectional view taken along the line CC in FIG. 3, FIG. 8 is a detailed view of a portion G in FIG. 4 is a cross-sectional view taken along line E-E in FIG. 4, FIG. 11 is a cross-sectional view taken along line FF in FIG. 4, FIG. 12 is a detailed view of portion I in FIG.

  The tunnel excavator described in the present embodiment supplies mud into the face and the chamber, and discharges excavated soil together with mud while facing the earth pressure and the water pressure with the mud pressure while stabilizing the face. It is a muddy water type shield excavator that constructs a tunnel.

  As shown in FIG. 1, this muddy water type shield excavator has a circular shape (in the skin plate 1 of the excavator body) in order to join the branch shield mine to the main machine shield mine in a space tunnel ramp portion or the like. The normal cross section) tunnel T1 having a circular cross section where the segment S1 is assembled is partially reduced in width from a tunnel T2 having a D type cross section where the D type (new cross section) segment S2 is assembled.

  At this time, steel impermeable partition units 2 and 3 extending in a plurality of stages (two stages in the illustrated example) in the front-rear direction (tunnel excavation direction) are used. The impermeable partition units 2 and 3 are formed in a box shape having a size so as to fill a cross-sectional portion that has been reduced (changed) from a circular cross section to a D-shaped cross section to become an overexcavated portion. Further, the length (thickness) in the front-rear direction of the water-impervious partition units 2 and 3 is equal to the length of one ring of each of the segments S1 and S2.

  Further, as shown in FIG. 13, the first-stage water-impervious partition unit 2 is provided with water-stop slide plates 20 on the outer surfaces of both upper and lower corners, and is installed in the water-impervious partition unit 2. The water stop slide plate expansion / contraction jack 21 can extend and retract in the circumferential direction of the skin plate 1. In the illustrated example, the water stop slide plate 20 extends outwardly by extension of the water stop slide plate telescopic jack 21, and the tip of the water stop slide plate 20 comes into contact with the outer surface of the corner portion of the D-type segment S 2. The gap between the opposing surfaces to S2 can be sealed. In FIG. 13, reference numeral 22 denotes a bracket for connecting the water stop slide plate 20 and the water stop slide plate telescopic jack 21 (the piston rod end thereof), and 2 a is a long hole of the water blocking partition unit 2 that allows the bracket 22 to move. It is. A plurality of water stop slide plate telescopic jacks 21 may be installed in the casing 23 in the front-rear direction.

  When the tunnel T1 having the circular cross section is transferred to the tunnel T2 having the D-shaped cross section, the process shown in FIGS. 2 and 3 is performed. When the tunnel T2 having the D-shaped cross section is transferred to the tunnel T1 having the circular cross section, FIG. And it is enforced at the process shown in FIG.

  That is, first, when the excavator body (skin plate 1) reaches the tunnel cross-section width reduction start position (tunnel new cross-section start position), the shield jack (main propulsion jack) 4 for the circular segment S1 and the D-type segment S2 are used. D-shaped bulkhead segment (joint segment) having a function of receiving a counterplate and a reaction plate by an erector device (not shown), etc., continuously with the circular segment S1 while shrinking the shield jack (sub-promotion jack) 5 to an appropriate number. ) Assemble S3. (Refer to FIG. 2A)

  Next, the shield jack 4 for the circular segment S1 and the shield jack 5 for the D-type segment S2 are extended to advance the excavator body (skin plate 1), and after cutting the face by rotating the cutter head (not shown), The first stage water-blocking partition unit 2 is installed in such a manner that the shield jack 4 for the circular segment S1 and the shield jack 5 for the D-type segment S2 are shrunk to an appropriate number and are continuously connected to the D-type partition segment S3. The D-type partition wall segment S3 and the bolt 6 are connected. (Refer to FIG. 2B)

  Next, the tail seal device 8 having the same structure as the tail seal device 7 attached to the rear end portion of the skin plate 1 is attached to the inner surface of the impermeable partition unit 2 (the surface facing the D-shaped segment S2 described later). After wearing, the D-type segment S2 is assembled in the water-impervious partition unit 2 so as to be continuous with the D-type partition segment S3. The tail seal devices 7 and 8 are well-known devices in which a belt-shaped device made of a wire brush is provided in a plurality of stages (three stages in the illustrated example) in the front-rear direction. (Refer to FIG. 2B)

  Next, the water blocking slide plate telescopic jack 21 in the water blocking partition unit 2 is extended to bring the tip of the water blocking slide plate 20 into contact with the outer surface of the corner portion of the D type segment S2, so that the water blocking partition unit 2 and the D type The gap between the opposed surfaces to the segment S2 is sealed. (See FIG. 3 (c) and FIG. 6)

  Next, after extending the shield jack 4 for the circular segment S1 and the shield jack 5 for the D-type segment S2 to advance the excavator body (skin plate 1) and excavating the face by rotating the cutter head, the circular segment The S1 shield jack 4 and the D-type segment S2 shield jack 5 are shrunk to an appropriate number while being connected to the water barrier unit 2 and the second stage water barrier unit 3 is installed and excavated. The machine body (skin plate 1) and the bracket 9 are used for fixing with bolts 10. (Refer to FIG. 3C)

  Next, after the impermeable partition unit 2 and the impermeable partition unit 3 are coupled with the bolts 11, the inner surface of the impermeable partition unit 3 (surface facing a D-shaped segment S <b> 2 described later) and the impermeable partition unit 3 are combined. A tail seal device 12 having the same structure as the tail seal device 7 attached to the rear end of the skin plate 1 on the inner surface of the corresponding excavator body (skin plate 1) (the surface facing a D-shaped segment S2 described later). , 13 is installed. (See FIG. 3C, FIG. 7 and FIG. 8)

  Next, the D-type segment S2 is assembled in the impermeable partition unit 3 so as to be continuous with the existing D-type segment S2. Thereafter, the bolt 6 that joins the water barrier unit 2 and the D-shaped partition segment S3 is removed. (See FIG. 3 (c) and FIG. 7)

  Next, the shield jack 4 and the shield jack 5 for the D-type segment S2 excluding the one corresponding to the D-type segment S2 for the circular segment S1, that is, the one that contacts the housing portion 3a of the water-blocking partition unit 3 are extended. The excavator body (skin plate 1) moves forward and the cutter head rotates to excavate the face, and the impermeable partition unit 2 and the impermeable partition unit 3 move together with the excavator body (skin plate 1). Then, the outer peripheral surface of the D-shaped segment S2 is in sliding contact. At this time, the water stop slide plate telescopic jack 21 in the water-impervious partition unit 2 is contracted in advance, and the tip of the water stop slide plate 20 is separated from the outer surface of the corner of the D-shaped segment S2. (See FIGS. 3C to 3D and FIG. 9)

  Next, the D-type segment S2 is placed in the space formed in the water-impervious partition unit 3 while the shield jack 4 for the extended circular segment S1 and the shield jack 5 for the D-type segment S2 are contracted to an appropriate number. Then, it is assembled in succession to the existing D-shaped segment S2. (Refer to FIG. 3D)

  Thereafter, by repeating this, a tunnel T2 having a D-shaped cross section is constructed. At this time, a backfilling agent is appropriately injected into the extra space.

  When the excavator body (skin plate 1) reaches the final position of the tunnel cross-section width reduction (final position of the new tunnel cross-section), first, the water stop slide plate expansion / contraction jack 21 in the water blocking partition unit 2 is extended to stop the water stop slide. The tip of the plate 20 is brought into contact with the outer surface of the corner portion of the D-shaped segment S2, and water is stopped as a circular segment ring. At this time, if necessary, a water stop material is injected into the gap between the opposing surfaces of the water-impervious partition unit 2 and the D-shaped segment S2. (See FIG. 4 (e) and FIG. 10)

  Next, the bracket 9 and the bolt 10 for fixing the impermeable partition unit 3 and the excavator main body (skin plate 1) are removed, while the impermeable partition unit 3 is fixed to the final D-shaped segment S2 by the fixing plate 14 and the bolt 15. Join. (See FIG. 4 (e), FIG. 11, and FIG. 12)

  Next, after extending all the shield jacks 4 for the circular segment S1 and the shield jack 5 for the D-type segment S2 to advance the excavator body (skin plate 1) and excavating the face by rotating the cutter head, All of the shield jacks 5 for the D-type segment S2 are contracted to the maximum extent (assumed to be used), and the shield jacks 4 for the circular segment S1 are contracted to an appropriate number, while the water-shielding partition unit 3 and the final D-type segment Continuing from S2, a circular segment (joint segment) S1 is assembled. At this time, the water barrier unit 3 and the final D-shaped segment S2 and the circular segment (joint segment) S1 are coupled by the bolt 16. (Refer to (e) in FIG. 4)

  Next, all the shield jacks 4 for the circular segment S1 are extended to advance the excavator body (skin plate 1) by two rings of the circular segment S1, and after cutting the face by rotating the cutter head, the circular segment S1 A new circular segment S1 is assembled by continuing to the existing circular segment S1 while shrinking the shield jacks 4 for an appropriate number. At this time, prior to newly assembling the circular segment S1, the tail seal device 13 near the rear end of the excavator body (skin plate 1) located at the assembly position is removed. (Refer to (f) in FIG. 4 and (g) in FIG. 5)

  Thereafter, by repeating this, the tunnel T1 having a circular cross section is built again.

  In this way, in this embodiment, when the tunnel T1 having a circular cross section is transferred to the tunnel T2 having a D-shaped cross section, the tail seal devices 8 and 12 are sized so as to fill the cross-sectional portion that has become an excessively dug portion. Are attached to the rear end of the excavator main body (skin plate 1) and connected to the tail seal device 12 of the second stage impermeable bulkhead unit 3 ( Since the tail seal device 13 is also mounted near the rear end of the skin plate 1), and the impermeable partition units 2 and 3 are brought into sliding contact with the sequentially assembled D-type segment S2 during excavation, the excavator body By cooperating with the tail seal device 7 attached to the rear end portion of the (skin plate 1), it is possible to easily reduce a part of the tunnel cross section while ensuring sufficient water-stopping.

  Moreover, since the water-impervious partition unit 3 is provided and the water-impervious partition unit 2 is reinforced by the two-stage structure, the water-stopping property is stably secured over a long period of time. Note that the water-blocking partition unit 3 is not particularly required as long as the water-blocking partition unit 2 can maintain sufficient strength. In this case, the excavator is connected to the tail seal device 3 of the water-blocking partition unit 2. The tail seal device 13 is attached near the rear end of the main body (skin plate 1).

  In addition, when installing the water-blocking partition unit 3, the water-stop slide plate telescopic jack 21 in the water-blocking partition unit 2 is extended in advance so that the tip of the water-stop slide plate 20 contacts the outer surface of the corner of the D-shaped segment S 2. Since the gap between the opposing surfaces of the impermeable partition unit 2 and the D-shaped segment S2 is sealed, the installation operation of the impermeable partition unit 3 and the tail seal devices 12 and 13 can be performed under conditions that ensure sufficient water blocking. Can be installed. During excavation in the D-type segment S2, the tail seal device 12 of the impermeable partition unit 3 and the tail seal device 13 near the rear end of the excavator main body (skin plate 1) can sufficiently secure water blocking. The water stop slide plate telescopic jack 21 in the water partition unit 2 may be contracted so that the tip of the water stop slide plate 20 is separated from the outer surface of the corner of the D-shaped segment S2.

  In addition, when moving from the tunnel T2 having a D-shaped cross section to the tunnel T1 having a circular cross section, the impermeable partition units 2 and 3 are left on the ground, so that they can function as a girdle in the reduced width portion of the tunnel. It is not necessary to assemble the D-type partition wall segment S3 or the like or to remove the water-impervious partition units 2 and 3, and the workability is further improved. At this time, the water stop slide plate telescopic jack 21 in the water blocking partition unit 2 is extended to bring the tip of the water stop slide plate 20 into contact with the outer surface of the corner portion of the D-shaped segment S2 to stop water as a circular segment ring. Therefore, it is possible to obtain a twill function with high water-stopping capability.

  Further, when installing the water-impervious partition unit 2, the water-impervious partition unit 2 is temporarily coupled to the D-type partition segment S3 by the bolt 6, so that the positioning of the water-impervious partition unit 2 is ensured, Subsequent attachment of the tail seal device 8 and installation of the impermeable partition unit 3 are facilitated.

  Needless to say, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the present invention. Further, the present invention is applicable not only to the circular normal section of the tunnel but also to a new cross section that is changed not only in the D shape but also in other shapes. Furthermore, although this invention showed the example using a muddy water type | mold shield excavator, you may use an earth pressure type shield excavator.

It is a rear view of the tunnel excavator which shows one Example of this invention. It is process drawing of the tunnel variable cross-section construction method by the tunnel excavator of FIG. FIG. 2 is a process diagram of a tunnel variable section construction method using the tunnel excavator of FIG. 1. FIG. 2 is a process diagram of a tunnel variable section construction method using the tunnel excavator of FIG. 1. FIG. 2 is a process diagram of a tunnel variable section construction method using the tunnel excavator of FIG. 1. It is the BB sectional view taken on the line of FIG. It is CC sectional view taken on the line of FIG. FIG. 8 is a detailed view of a G part in FIG. 7. It is the DD sectional view taken on the line of FIG. It is the EE sectional view taken on the line of FIG. It is the FF sectional view taken on the line of FIG. FIG. 12 is a detailed view of a portion I in FIG. 11. FIG. 2 is a detailed view of a portion J in FIG. 1.

Explanation of symbols

1 Skin plate (excavator body)
2 First-stage impermeable bulkhead unit 3 Second-stage impermeable bulkhead unit 4 Shield jack for circular segment (main propulsion jack)
5 Shield jack for D type segment (sub propulsion jack)
6 Bolt 7 Tail seal device at the rear end of the skin plate 8 Tail seal device of the water-blocking partition unit 2 9 Bracket 10 Bolt 11 Bolt 12 Tail seal device of the water-blocking partition unit 3 13 Tail seal device near the rear end of the skin plate 14 Fixing Plate 15 Bolt 16 Bolt S1 Circular segment S2 D-type segment S3 D-type bulkhead segment T1 Circular cross-section tunnel T2 D-type cross-section tunnel

Claims (4)

Assembling a new section bulkhead segment having a function of a countersink and a counterplate in succession to the existing normal section segment when the excavator body reaches the tunnel new section start position;
Installing a water-blocking partition wall unit having a size corresponding to a cross-sectional portion that has been continuously dug into the new section partition wall segment;
Attaching a tail seal device to the inner surface of the impermeable partition unit and the rear end of the excavator body corresponding to the impermeable partition unit;
Assembling a new cross-sectional segment in the impermeable partition unit;
Coupling the water barrier unit to an excavator body;
Sequentially assembling the new cross-sectional segments for a predetermined number of rings;
When the excavator body reaches the final position of the new cross section of the tunnel, the step of coupling the impermeable bulkhead unit to the final new cross section segment while uncoupling the excavator body;
Assembling a normal cross-sectional segment in succession to the impermeable partition unit and the final new cross-sectional segment;
Coupling the normal cross-sectional segment to the water barrier unit and the final new cross-sectional segment;
Are performed sequentially,
After the step of assembling the new cross section segment in the water barrier partition unit, another water barrier partition unit is installed, the water barrier partition unit is combined with the existing water barrier partition unit, and the existing water barrier partition unit is installed. Instead of connecting to the excavator body,
Further, prior to the installation of the second-stage impermeable partition unit, a water-stop slide plate mounted on the existing impermeable partition unit is overhanged, and its tip abuts against the outer surface of the corner of the new section segment. The tunnel variable section construction method characterized by sealing the gap between the opposing surfaces of the impermeable partition unit and the new section segment .   The tunnel variable section construction method according to claim 1, wherein, in the step of installing the impermeable partition unit, the impermeable partition unit is temporarily coupled to the new sectional partition segment. A tunnel excavator used when performing the tunnel variable section construction method according to claim 1 or 2,
An excavator body having a main propulsion jack that takes a reaction force on an existing normal cross-section segment and a sub-propulsion jack that takes a reaction force on an existing new cross-section segment, and a tail seal device at the rear end of the skin plate;
When changing from a tunnel with a normal cross section to a tunnel with a new cross section, it is installed at the rear end of the skin plate, and has a water shielding partition unit with a tail seal device on its inner peripheral surface,
Have
The impermeable partition unit is formed to have a size to fill a cross-sectional portion that has been changed to a dug by changing the tunnel,
In addition to the tail seal device attached to the rear end of the skin plate, a tail seal device newly attached is provided near the rear end of the skin plate corresponding to the water-impervious partition unit. Tunnel excavator. An excavator body having a main propulsion jack that takes a reaction force on an existing normal cross-section segment and a sub-propulsion jack that takes a reaction force on an existing new cross-section segment, and a tail seal device at the rear end of the skin plate;
When changing from a normal cross-section tunnel to a new cross-section tunnel, it is installed at the rear end of the skin plate, and has a water-impervious partition unit equipped with a tail seal device on its inner peripheral surface,
Have
The impermeable partition unit is formed to have a size to fill a cross-sectional portion that has been changed to a dug by changing the tunnel,
Near the rear end of the skin plate corresponding to the water-impervious partition unit, a tail seal device newly attached in addition to the tail seal device attached to the rear end portion of the skin plate ,
Further, the water barrier partition unit is provided in a plurality of stages in the tunnel excavation direction .

Images