JP2009046809A - Method and equipment for maintaining tail seal of shield machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and equipment for maintaining a tail seal of a shield machine, which enable a reduction in the risk of ignition, an increase in working efficiency, and the realization of high water sealability when maintenance such as the replacement of the tail seal is performed. <P>SOLUTION: The tail seal 20 is provided in the rear of the external cylinder section 10 of the shield machine 1. When the maintenance of the tail seal 20 is performed, a special segment S1 provided with an ice packing creation pipe 25 is installed as a segment S, and a cooling fluid is circulated and supplied into the ice packing creation pipe 25, so that ice packing P can be formed on natural ground between the external cylinder section 10 and the segment S. The maintenance of the tail seal 20 is performed by applying water sealing to a section between the external cylinder section 10 and the segment S by means of the ice packing P. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method and an apparatus for maintaining a tail seal in a shield machine.

  In the shield machine, a tail seal is provided on the rear side in order to prevent groundwater from entering the inside of the outer cylinder part from between the outer cylinder part and the segment. The tail seal is provided at the rear end portion of the outer cylinder portion, and its front end seals with the segment to stop water between the outer cylinder portion and the segment. Since this tail seal wears as the excavation progresses in the shield excavator, the tail seal is appropriately replaced or repaired.

When exchanging the tail seal or the like, it is necessary to stop water between the outer tube portion and the segment. As a method of stopping water between the outer cylinder and the segment when replacing the tail seal, etc., a tail seal made of urethane foam is conventionally provided at the tip of the segment, and the outer cylinder and segment are provided with this tail seal. There is an emergency water stop device for a tail seal of a shield machine that stops water between them (for example, Patent Document 1).
JP-A-10-131683

  However, in the emergency water stop device disclosed in Patent Document 1, the tail seal provided in the segment is pressed against the outer cylinder portion to stop water. For this reason, although a high water-stopping property is obtained, there is room for further increasing the water-stopping property. Also, urethane foam is used as a tail seal. Since the urethane foam is flammable, there is a problem that the urethane foam may be ignited when a gas cutter is used when removing the tail seal. In addition, when a new tail seal is to be installed, welding must be performed. Therefore, it is necessary to proceed carefully so as not to ignite the tail seal seal, and there is a problem that work efficiency is poor.

  Accordingly, an object of the present invention is to provide a tail in a shield machine capable of reducing the risk of ignition, improving work efficiency, and realizing high water stoppage when performing maintenance such as replacement of a tail seal seal. It is an object of the present invention to provide a seal maintenance method and apparatus.

  The tail seal maintenance method in the shield machine according to the present invention that solves the above problems includes a tail seal provided at the rear end portion of the outer cylinder portion, and the rear assembled segment and the inside of the outer cylinder portion are connected by the tail seal. In order to maintain the tail seal in the shield machine that prevents the intrusion of groundwater into the outer cylinder by closing it, the ground in the position immediately after the tail seal is frozen by a freezing device so that the space between the outer cylinder and the segment After the formation of frozen soil, the tail seal is maintained.

  In the maintenance method of the tail seal in the shield machine according to the present invention, the natural ground immediately after the tail seal is frozen by a freezing device, and the natural ground is frozen to form frozen soil (ice packing). By forming this ice packing, when removing the tail seal from the outer cylinder part, it is possible to prevent groundwater from flowing into the outer cylinder part from between the rear end part of the outer cylinder part and the segment. it can. Therefore, since the high water-stopping property using foamed urethane or the like can be exhibited when performing maintenance such as replacement of the tail seal, the risk of ignition can be reduced. In addition, since the water can be reliably stopped between the rear end portion of the outer cylinder portion and the segment, it is possible to improve the work efficiency such as the replacement operation of the tail seal and to achieve high water stoppage.

  The maintenance of the tail seal referred to in the present invention refers to general maintenance of the tail seal and the like, and refers to operations such as cleaning, replacement, repair, maintenance of the tail seal, and removal of foreign matter that has entered between the tail seal members. .

Here, the tail seal is composed of a plurality of tail seal members spaced apart along the extending direction of the outer cylinder portion, and the freezing device is a tail seal member at the rearmost portion of the plurality of tail seal members. It can be set as the aspect which freezes the natural ground in the position immediately after.
It can be set as the aspect which freezes the natural ground in the position immediately after a steel member.

  As described above, the freezing device can easily perform maintenance work on the front tail seal member by freezing the natural ground immediately after the tail seal member at the rearmost portion of the plurality of tail seal members. .

  In addition, the maintenance of the tail seal may be an aspect in which the tail seal member is replaced or a foreign matter that has entered between the tail seal members is removed. A typical example of the foreign matter here is a backfilling injection material.

  On the other hand, the tail seal maintenance device in the shield machine according to the present invention that solves the above problems is used in the tail seal maintenance method in the shield machine, and the freezing device has a tail just before the ground to be frozen. It is provided in the segment that contacts the seal.

  Since the freezing device is provided in the segment that comes into contact with the tail seal immediately before the ground to be frozen, the ground behind the tail seal can be easily frozen.

  Here, the freezing apparatus can be configured to be provided at the tip of the segment.

  By providing the freezing device at the tip of the segment, it is possible to directly freeze the natural ground between the segment located at the forefront and the outer cylinder. For this reason, the rear end of the outer cylinder and the tip of the segment can be prevented from overlapping each other when viewed from the side, so that the tail of the rear part from the inside of the outer cylinder does not interfere with the segment. The seal can be easily maintained.

  In addition, the freezing device is used in the method for maintaining the tail seal in the shield machine, and the freezing device is provided at a position where the tail seal is attached at a position immediately before the natural ground to be frozen in the outer cylinder portion. You can also

  Since the freezing device is provided at this position, the ground behind the tail seal can be easily frozen.

  According to the tail seal maintenance method and apparatus in the shield machine according to the present invention, when performing maintenance such as replacement of the tail seal, the risk of ignition is reduced, work efficiency is improved, and further, high water-stopping performance is achieved. Can be realized.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In each embodiment, portions having the same function are denoted by the same reference numerals, and redundant description may be omitted. FIG. 1 is a side sectional view of a shield machine equipped with a tail seal maintenance device according to a first embodiment of the present invention, and FIG. 2 is an enlarged side sectional view of a rear end portion of the shield machine according to an embodiment of the present invention. is there.

  As shown in FIG. 1, the shield machine 1 according to this embodiment includes an outer cylinder portion 10. A shield jack 17 is provided at the rear portion of the outer cylinder portion 10. The shield jack 17 includes a shield jack cylinder 17B and a shield jack rod 17A, and the tip of the shield jack rod 17A presses the assembled segment S. By pressing the segment S with the shield jack rod 17A, a reaction force is applied to the segment S to advance the shield machine 1.

  Further, a tail seal 20 is provided at the rear end portion of the outer cylinder portion 10. The tail seal 20 stops water between the segment S and the shield machine 1 at the rear end portion of the shield machine 1, and prevents intrusion of groundwater and earth and sand in the natural ground. As shown in FIG. 2, the tail seal 20 includes a first stage tail seal member (hereinafter referred to as “first tail seal member”) 21 and a second stage tail seal member (hereinafter referred to as “second tail seal member”) 22. And a third-stage tail seal member (hereinafter referred to as “third tail seal member”) 23. Among them, the third tail seal member 23 is provided at the innermost rearmost end portion of the outer cylinder portion 10, the second tail seal member 22 is provided in front of the inner cylinder portion 10, and the outer cylinder portion 10. Further, a first tail seal member 21 is provided in front of the first tail seal member 21. The segment S assembled rearward and the inner side of the outer cylinder part 10 are closed by the tail seal 20 to prevent intrusion of earth and sand into the outer cylinder part 10.

  Further, an insertion hole in which a thermometer can be inserted is formed at the rear end portion of the outer cylinder portion 10. A thermometer T is always inserted into the insertion hole, and the temperature of the natural ground around the outer tube portion 10 can be measured by the thermometer T. On the other hand, in the segment S assembled as a shield tunnel, the special segment S1 located at the forefront is provided with an ice packing forming pipe 25 through which a cooling fluid is circulated and supplied. In addition, as a cooling fluid, the liquid and gas which a cooling fluid has cold heat, for example, liquid nitrogen, gaseous nitrogen, etc. can be used. Alternatively, a refrigerant (brine) such as a fluid gas cooled by absorbing cold heat such as liquid nitrogen can be used.

  As shown in FIG. 3, O-rings 26 are interposed at the connecting positions of the ice packing forming pipes 25 between the special segments S1. The ice packing forming pipes 25 are connected to each other through the O-ring 26. However, as shown in FIG. 4, the ice packing forming pipes 25 between the special segments S <b> 1 can be connected by a flexible hose 27.

  As shown in FIG. 1, a refrigerant tank 24 is connected to the ice packing forming tube 25, and a cooling fluid having a negative temperature circulates with respect to the ice packing forming tube 25 by operating a pump (not shown). Supplied. The cooling fluid is circulated and supplied to the ice packing forming tube 25, so that the natural ground in the vicinity of the rear end portion of the outer cylinder portion 10 can be frozen.

  Next, the procedure of the tail seal maintenance method in the shield machine 1 according to this embodiment will be described. Here, an example of performing a tail seal replacement operation as a tail seal maintenance method will be described.

  When excavating with the shield machine 1, the ground is excavated by rotating the cutter head 11. Further, when the shield machine 1 is advanced, the shield jack 17 is repeatedly expanded and contracted, and the segment S is assembled when the shield machine 1 is advanced. As the segment S, a normal segment S2 in which the ice packing forming tube 25 is not provided is used. Further, behind the rear end portion of the outer cylinder portion 10, a backfilling injection material is injected between the assembled segment S and the natural ground by a backfilling injection device (not shown).

  When the shield machine 1 digs, a tail seal 20 is provided at the rear end of the shield machine 1, and the tail seal 20 stops between the rear end of the shield machine 1 and the segment S. Water is planned. However, when the shield machine 1 advances, wear or the like occurs in the tail seal 20 and water leakage W starts to occur as shown in FIG. When the water leak W occurs, the tail seal 20 needs to be replaced. The replacement of the tail seal 20 is performed as follows.

  When it is time to replace the tail seal 20, as shown in FIG. 5B, the special segment S <b> 1 provided with the ice packing forming tube 25 is assembled at the tip as the segment S. Subsequently, the excavation is further advanced, and the normal segment S2 is assembled at the tip as shown in FIG. At this time, the cooling fluid is circulated and supplied to the ice packing forming pipe 25 in the special segment S1, and freezing of the natural ground between the outer cylinder portion 10 and the segment S is started.

  While freezing the natural ground, the thermometer T is inserted into the insertion hole to control the temperature of the earth and sand in the natural ground. In the temperature management, it is confirmed whether or not the temperature of the natural mountain is 0 ° C. or less. If the natural mountain temperature is 0 ° C. or less, it is determined that the natural mountain is frozen. When a certain amount of time has passed after freezing of the natural ground, as shown in FIG. 5 (d), there is an ice packing P serving as frozen soil between the rear end portion of the outer cylinder portion 10 and the segment S. It is formed. The ice packing P is formed along the third tail seal member 23 located at the rearmost part. By forming the ice packing P, water leakage from between the rear end portion of the outer cylinder portion 10 and the segment S is prevented.

  When the ice packing P is formed over the entire circumference of the shield machine 1 between the outer cylinder portion 10 and the segment S in this way, the segment S once attached is removed as shown in FIG. The first tail seal member 21 and the second tail seal member 22 are made visible from the inside. Thereafter, as shown in FIG. 6B, the first tail seal member 21 and the second tail seal member 22 are removed, and the first tail seal member 21 and the second tail seal member 22 are replaced. During this time, the cooling fluid is continuously circulated and supplied to the ice packing forming tube 25 to maintain the ice packing P formed between the rear end portion of the outer cylinder portion 10 and the segment S.

  Thereafter, as shown in FIG. 6C, new articles are attached as the first tail seal member 21 and the second tail seal member 22. And the circulation supply of the cooling fluid in the ice packing formation pipe | tube 25 is stopped, and the ice packing P is thawed | decompressed as shown in FIG.6 (d). Then, the removed segment S is attached again, and the excavation in the shield machine 1 is resumed.

  As described above, in the shield machine 1 according to the present embodiment, when the first tail seal member 21 and the second tail seal member 22 are replaced, the cooling fluid is circulated and supplied to the ice packing forming pipe 25 to The packing P is formed, and the space between the outer cylinder portion 10 and the segment S is stopped. For this reason, the first tail seal member 21 and the second tail seal member 22 can be exchanged while preventing leakage of water into the outer cylinder part 10 from the rear of the outer cylinder part 10. At this time, since it is not necessary to use urethane foam or the like, it is possible to reduce the risk of ignition during the replacement operation of the tail seal. In addition, since the water can be reliably stopped between the rear end portion of the outer cylinder portion 10 and the segment S, it is possible to improve work efficiency such as a replacement operation of the tail seal and to realize high water stoppage.

  Next, the case where the 3rd tail seal member 23 located in the last part is replaced | exchanged is demonstrated. When exchanging the third tail seal member 23, as shown in FIG. 7A, a special segment S3 having an ice packing forming tube 25 provided at the tip is used as the segment S. When the third tail seal member 23 is replaced, the ice packing P is formed between the outer cylinder portion 10 and the segment S by circulating and supplying a cooling fluid to the ice packing forming pipe 25 in the special segment S3.

  For example, when the third tail seal member 23 is replaced using the special segment S1 used when the first tail seal member 21 and the second tail seal member 22 are replaced, as shown in FIG. When viewed from the side, the rear end portion of the outer cylinder portion 10 and the front end portion of the special segment S1 overlap each other. For this reason, even if it is going to replace the 3rd tail seal member 23 from the inner side of the outer cylinder part 10, it will be difficult for a worker's hand etc. to reach, and it will take time to replace the 3rd tail seal member 23.

  In this regard, if the special segment S3 provided with the ice packing forming tube 25 is used, the rear end portion of the outer cylinder portion 10 and the tip end portion of the segment S can be prevented from overlapping, and the operator's hand or the like can be used. The third tail seal member 23 can be easily reached. For this reason, the replacement | exchange operation | work of the 3rd tail seal member 23 can be performed easily.

  Further, as the excavation by the shield machine 1 proceeds, as shown in FIG. 8, the backfilling injection material U by the backfilling injection device gradually exceeds the third tail seal member 23 to the first tail seal member 21. The first tail seal member 21 stays between the third tail seal member 23. If the retention amount of the backfilling injection material U becomes large, the water stoppage due to the tail seal 20 is lowered, so that it is necessary to remove the retained backfilling injection material U.

  When performing such an operation of removing the backfilling injection material U, as shown in FIG. 8, the outer cylinder portion is used in the same manner as the operation of replacing the third tail seal member 23 using the special segment S3. Ice packing P is created between 10 and segment S. By creating the ice packing P between the outer cylinder part 10 and the segment S, it is possible to prevent the leakage of groundwater in the outer cylinder part 10, so that the operation of removing the backfilling injection material U is performed reliably. be able to. Further, since the rear end portion of the outer cylinder portion 10 and the tip end portion of the segment S can be prevented from being overlapped, backfill injection is also performed between the second tail seal member 22 and the third tail seal member 23. The operation of removing the material U can be reliably performed.

  Next, a second embodiment of the present invention will be described. This embodiment differs in the attachment position of the ice packing formation pipe | tube 25 compared with the said 1st Embodiment. As shown in FIG. 9, in the tail seal maintenance device in the shield machine according to the present embodiment, an ice packing forming tube 25 is provided at the rear end portion of the outer cylinder portion 10. Further, when the ice packing forming pipe 25 is provided in the outer cylinder portion 10, the thermometer T is provided in the segment S.

  As shown in FIG. 10 (a), the mounting position of the ice packing forming tube 25 in the outer cylinder part 10 is the outside of the outer cylinder part 10, the inside of the outer cylinder part 10 as shown in FIG. As shown in FIG. 10C, any position inside the outer cylinder portion 10 can be used. In addition, a refrigerant tank 24 is connected to the ice packing forming pipe 25, and a cooling fluid having a negative temperature is circulated and supplied to the ice packing forming pipe 25 by operating a pump (not shown).

  When the cooling fluid is circulated and supplied to the ice packing forming tube 25, when the ice packing forming tube 25 is provided outside the outer cylinder portion 10, as shown by a broken line A in FIG. A flow path for supplying a fluid to the ice packing forming tube 25 is provided outside the outer cylinder portion 10. Further, when the ice packing forming pipe 25 is provided inside the outer cylinder part 10, as shown by a broken line B, a flow path for supplying the cooling fluid to the ice packing forming pipe 25 is provided as the outer cylinder part 10. Provided inside. Further, when the ice packing forming tube 25 is provided outside the outer cylinder portion 10, as shown by a broken line C, a flow path for supplying the cooling fluid to the ice packing forming tube 25 is provided as the outer cylinder portion 10. Provide inside.

  Thus, even when the ice packing forming pipe 25 is provided in the outer cylinder portion 10 of the shield machine 1, the cooling medium is circulated and supplied to the ice packing forming tube 25 so that the vicinity of the rear end portion of the outer cylinder portion 10 is around. The natural mountain in can be frozen. And the water between the outer cylinder part 10 and the segment S can be stopped by freezing a natural ground and creating ice packing. For this reason, the maintenance work of the tail seal 20 can be performed while preventing leakage of water into the outer cylinder part 10 from behind the outer cylinder part 10.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to the above embodiment. For example, in the above embodiment, the thermometer T is kept provided, but when the ice packing P is formed, the thermometer can be inserted into the insertion hole. Furthermore, maintenance of the tail seal can include operations such as tail seal maintenance and inspection in addition to tail seal replacement and foreign matter removal. Moreover, as a foreign material, the earth and sand which flows in from a natural ground other than backfilling injection material may be sufficient. Furthermore, a freezing apparatus other than the freezing pipe can be used.

It is a sectional side view of the shield machine which concerns on a 1st form. It is an expanded sectional side view of the rear-end part in a shield machine. It is a front sectional view of a segment provided with an O-ring. It is a front sectional view of a segment in which ice packing forming tubes are connected by a flexible hose. It is process drawing which looked at the process of exchanging tail seals from the side. FIG. 6 is a process diagram illustrating a process following the process in FIG. 5. (A) is a side sectional view of a tail seal in which an ice packing is formed using a special segment, and (b) is a side sectional view of a tail seal in which an ice packing is formed using a special segment. It is side sectional drawing of the tail seal in which backfilling injection material stagnates. It is a sectional side view of the shield machine which concerns on a 2nd form. It is an expanded side sectional view of the rear end part in a shield machine, (a) when an ice packing forming pipe is provided outside the outer cylinder part, (b) is provided with an ice packing forming pipe inside the outer cylinder part (C) is a case where an ice packing forming tube is provided on the side of the outer cylinder portion. It is an expanded sectional side view of the rear-end part in a shield machine.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Shield machine 10 ... Outer cylinder part 11A ... Cutter bit 11 ... Cutter head 12 ... Partition plate 13 ... Chamber 14 ... Rotating shaft 15 ... Mud pipe 16 ... Mud pipe 17 ... Shield jack 17B ... Shield jack cylinder 17A ... Shield jack rod 20 ... tail seal 21 ... first tail seal member 22 ... second tail seal member 23 ... third tail seal member 24 ... refrigerant tank 25 ... ice packing formation tube 26 ... O-ring 27 ... flexible hose P ... ice packing S ... Segment S1 ... Special segment S2 ... Normal segment S3 ... Special segment T ... Thermometer U ... Backfill injection material W ... Water leakage

Claims (6)

A shield machine in which a tail seal is provided at the rear end portion of the outer cylinder portion, and the rear assembled segment and the inner side of the outer cylinder portion are closed by the tail seal, thereby preventing intrusion of groundwater into the outer cylinder portion. In preparing the tail seal in
In a shield machine, wherein the natural ground immediately after the tail seal is frozen by a freezing device, and frozen soil is formed between the outer tube portion and the segment, and then the tail seal is maintained. How to maintain the tail seal. The tail seal is composed of a plurality of tail seal members that are spaced apart along the extending direction of the outer cylinder portion,
2. The method for maintaining a tail seal in a shield machine according to claim 1, wherein the freezing device freezes a ground in a position immediately after a tail seal member at a rearmost portion of the plurality of tail seal members.   The method for maintaining a tail seal in a shield machine according to claim 1, wherein the maintenance of the tail seal is a replacement operation of a tail seal member or a removal operation of foreign matter that has entered between the tail seal members. It is used for the maintenance method of the tail seal in the shield machine according to any one of claims 1 to 3,
A tail seal maintenance device in a shield machine provided in a segment where the freezing device is in contact with a tail seal at a position immediately before a natural ground to be frozen.   The apparatus for tail seal maintenance in a shield machine according to claim 4, wherein the freezing device is provided at a tip of the segment. It is used for the maintenance method of the tail seal in the shield machine according to any one of claims 1 to 3,
The freezing device is a maintenance device for a tail seal in a shield machine provided at a position where a tail seal is attached at a position immediately before a natural ground to be frozen in the outer cylinder portion.

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