JP5495874B2 - Removal method of shield excavator - Google Patents

Description

  The present invention relates to a shield excavator removal method for removing at least a part of a shield excavator after excavation of a tunnel from the ground.

  Conventionally, a shield excavator that has been excavated in the ground has reached a vertical shaft, disassembled in the vertical shaft, and removed parts such as a cutter face and a shield jack from the ground (see Patent Document 1).

  In Patent Documents 1-3, a shield excavator excavated from one side and a shield excavator excavated from the opposite side face each other, and the two shield excavators are butted and joined to penetrate the tunnel. Is disclosed.

Japanese Patent Laid-Open No. 9-279986 JP-A-6-346686 JP 2005-126958 A

  However, the conventional method of removing the shield excavator from the vertical shaft requires the construction of a vertical shaft that reaches the depth at which the shield excavator is advanced. To do. In urban areas, it is necessary to consider the impact on the surrounding environment caused by noise and smoke generated from shafts during construction.

  Further, in the conventional method of joining two shield excavators in the ground, high excavation accuracy is required for both shield excavators. In addition, a shield excavator with a special structure for underground joints must be manufactured, and measures such as freezing around the joints as disclosed in Patent Document 2 are necessary, and the construction cost is high. It tends to be higher.

  Also, it is necessary to match the progress of the two shield excavators. If for some reason the arrival of one shield excavator is delayed, the other shield excavator completes the work even though the excavation has been completed. Can not do it.

  Therefore, the present invention eliminates the need to construct a vertical shaft, and even when connecting shield tunnels, the shield excavator can remove at least a part of the shield excavator from the ground regardless of the progress of the other. The purpose is to provide a removal method.

In order to achieve the above object, a method for removing a shield excavator according to the present invention is a method for removing a shield excavator by dismantling and removing at least part of a shield excavator excavated in the ground. the excavation was drilled ground of arrival position of the excavator, reaching a step of constructing a wall zone having a diaphragm wall of reinforced concrete structures by inserting the reinforcing bar cage, the shield excavator of the wall zone forming a water stopping zone ground side to the step of penetrating the front of the cutter face of the shield excavator inside of the diaphragm wall, the Kattafu E chair and internal partition walls of the shield excavator the a process for removal removed from the shield excavator, the thickness of the wall zone to be axially in the same direction of the shield excavator during the penetration, the cutter face Characterized in that al the up partition wall is not less than the length.

Here, a ground improvement part or a muddy water solidification wall can be constructed in the ground adjacent to the underground continuous wall as the wall body zone. The thickness of the front Kikabetai zone may also be at least twice the length to the bulkhead from the cutter face.

  The shield excavator removal method of the present invention configured as described above is configured such that a continuous underground wall of a concrete structure is constructed on the ground where the shield excavator reaches, and the shield excavator is directed toward the underground continuous wall. Dig up. Then, the cutter face of the shield excavator is penetrated into the underground continuous wall.

  For this reason, even if the bulkhead and the cutter face are removed and removed from the inside of the shield excavator, the opened front surface of the shield excavator is protected by the underground continuous wall, so that the removal work can be performed safely.

  And if it is the removal method of the shield excavator comprised in this way, even if it does not wait for the arrival of the shield excavator to join and the construction of a shaft on the arrival side, it reaches the planned arrival position At that point, the shield excavator can be removed.

  Moreover, the tunnel from which the cutter face has been removed can be stably maintained by making the thickness of the wall zone equal to or greater than the length from the cutter face of the shield excavator to be penetrated to the partition wall.

  In addition, the wall zone thickness is more than twice the length from the cutter face to the bulkhead, making it the opposite of tunnels built by shield excavators that have previously reached the underground continuous wall. It is possible to easily penetrate the two tunnels by connecting the shield excavator excavated from the side inside the underground continuous wall.

It is a perspective view explaining the removal method of the shield excavator of embodiment of this invention. It is sectional drawing explaining the process of constructing a wall zone. It is sectional drawing explaining the process of constructing a water stop zone. It is sectional drawing explaining the process of penetrating a shield excavator inside the underground continuous wall. It is sectional drawing explaining the process of removing a cutter face and a partition from a shield excavator. It is sectional drawing explaining the removal method of the shield excavator of an Example.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1-5 is a figure explaining the removal method of the shield excavator 1 of this Embodiment. The shield excavator 1 starts from a start shaft (not shown) serving as a start base, and after reaching a predetermined position on the ground G, the excavation is terminated.

  Thus, as a case where the excavation of the shield excavator 1 is completed in the middle of the ground G, there are the following cases. For example, when the shield excavators 1 and 1A excavating in opposite directions as shown in FIG. 6 are joined in the ground, when the arrival of one shield excavator 1A is delayed, the other shield excavator 1 The excavation may end first and enter a standby state.

  In addition, if there is no place to construct a shaft for reaching the shield excavator 1, there is no need to construct a shaft for reasons such as wanting to suppress environmental deterioration in the surrounding area, deadlines in time, or reducing construction costs. The excavation of the excavator 1 is terminated at a predetermined position on the ground G. Hereinafter, in the present embodiment, a case where a reaching shaft is not constructed will be described.

  As shown in FIGS. 1 and 4, the shield excavator 1 includes a disk-shaped cutter face 11 having a fishtail 11 a and a cutter bit 11 b on the front surface, and a cylindrical skin plate 12 extending rearward thereof. And a partition wall 13 that divides the inside of the skin plate 12 into a cutter face 11 side and a tunnel 10 side. A shield jack 14 and a mud pipe 15 are also arranged inside the shield excavator 1.

  In the present embodiment, as shown in FIG. 1, the underground continuous wall 3 is constructed in advance at a planned arrival position of the shield excavator 1. The underground continuous wall 3 has a reinforced concrete structure and has a predetermined rigidity as a structure.

  Moreover, although this underground continuous wall 3 can be constructed | assembled uniformly to the ground surface, it is set as the reinforced concrete structure only in the range as which predetermined | prescribed rigidity is required here, and the upper part is made into the muddy water solidification wall 31. FIG. The muddy water solidified wall 31 may have the same strength as the surrounding ground G. For example, the muddy water solidified wall 31 is formed by filling a solidified material into a digging groove excavated to construct the underground continuous wall 3.

  Furthermore, as shown in FIG. 1, the ground improvement part 4 is constructed | assembled in the ground G of the side which the shield excavator 1 of the underground continuous wall 3 reaches. The ground improvement unit 4 is formed by, for example, a deep mixing method in which cement milk is mixed with the ground G in the original position, or a soil cement column wall method in which a core material is not inserted.

  And this underground continuous wall 3 and the ground improvement part 4 are match | combined, and it is set as the wall body zone 30. FIG. The thickness necessary for the wall body zone 30 may be at least the length L from the front surface of the cutter face 11 of the shield excavator 1 (the tip of the fishtail 11a) to the partition wall 13. Here, the thickness of the underground continuous wall 3, the ground improvement part 4, and the wall body zone 30 refers to the same direction as the axial direction of the shield excavator 1 to be penetrated.

  In the present embodiment, as shown in FIG. 4, only the thickness B of the underground continuous wall 3 is equal to or longer than the length L from the front surface of the cutter face 11 to the partition wall 13. Therefore, it can be said that the wall zone 30 has a sufficient thickness. Moreover, the wall body zone 30 is formed in the height and width | variety which can cover the circumference | surroundings of the shield excavator 1 penetrated.

  Moreover, as shown in FIG. 1, the water stop zone 5 is formed in the ground G on the side where the shield excavator 1 reaches the wall zone 30. This water stop zone 5 is formed by, for example, injecting a chemical into the ground G. The water stop zone 5 prevents groundwater from flowing from the ground G into the shield excavator 1 penetrating into the wall zone 30.

  Next, the removal method of the shield excavator 1 of this Embodiment is demonstrated, referring FIGS. 2-5.

  First, as shown in FIG. 2, the ground improvement unit 4 is constructed in front of the ground G at the arrival position of the shield excavator 1. The ground improvement unit 4 is constructed by cutting the ground G having a predetermined depth from the ground surface with an auger or the like, and mixing while discharging cement milk.

  And the ground G of the position adjacent to this ground improvement part 4 is excavated in the shape of a groove | channel from the ground surface. This excavation is performed while protecting the hole wall with bentonite mud. Furthermore, a reinforced concrete rod (not shown) is inserted into the excavation groove formed in this manner, and concrete is poured into the underground continuous wall 3 made of reinforced concrete.

  As shown in FIG. 2, the underground continuous wall 3 is constructed to the same height as the ground improvement portion 4. Then, cement is poured into the excavation groove above the underground continuous wall 3 to harden bentonite mud and form a mud solidified wall 31. It should be noted that the construction order of the underground continuous wall 3 and the ground improvement unit 4 may be a process of constructing either one first.

  Subsequently, as shown in FIG. 3, the water stop zone 5 is formed by inserting an injection pipe from the ground surface and injecting a chemical solution into the ground G before the wall body zone 30. Thus, the side surface of the underground continuous wall 3 on the side where the shield excavator 1 is penetrated is covered with the ground improvement portion 4 and the water stop zone 5 having high water stoppage.

  Then, as shown in FIG. 4, the shield excavator 1 is advanced toward the underground continuous wall 3. A cylindrical tunnel 10 is formed behind the shield excavator 1 by assembling arc-shaped segments 2.

  Further, a backfilling material 21 having a high water-stopping property is injected into the outer periphery of the tunnel 10 from the rear part of the shield excavator 1. In the water stop zone 5, the backfill material 21 is filled between the segment 2 and the excavation surface of the water stop zone 5, and the water stop around the shield excavator 1 is ensured integrally with the water stop zone 5. The

  Thus, groundwater hardly flows around the shield excavator 1 that has passed through the water stop zone 5 and has reached the underground continuous wall 3 through the ground improvement section 4. Moreover, the periphery of the front surface of the shield excavator 1 is in a stable state covered with the underground continuous wall 3 having high rigidity.

  Therefore, after the excavation of the shield excavator 1 is completed, the equipment such as the shield jack 14 and the mud pipe 15 inside the shield excavator 1 is removed from the tunnel 10.

  Further, the partition wall 13 is cut from the shield excavator 1 and removed. Further, the front cutter face 11 is disassembled and removed. Thus, the shield excavator 1 from which the internal materials and equipment have been removed is in a state where only the skin plate 12 is left as shown in FIG.

  And the front-end | tip of the tunnel 10 from which the cutter face 11 was removed will be in the state where the cut wall surface of the underground continuous wall 3 was exposed. This wall surface may be left as it is, but if necessary, it is covered and protected by an iron plate or concrete.

  Next, the effect | action of the removal method of the shield excavator 1 of this Embodiment is demonstrated.

  In the method of removing the shield excavator 1 of the present embodiment configured as described above, the underground continuous wall 3 of the reinforced concrete structure is constructed in advance on the ground G at the position reached by the shield excavator 1, and the underground continuous The shield excavator 1 is advanced toward the wall 3. Then, the cutter face 11 of the shield excavator 1 is penetrated into the underground continuous wall 3.

  For this reason, even if the bulkhead 13 and the cutter face 11 are removed and removed from the inside of the shield excavator 1, the opened front surface of the shield excavator 1 is protected by the underground continuous wall 3, so that the removal work can be performed safely. Can be done.

  The shield excavator 1 is covered with the underground continuous wall 3 and the back thereof is covered with the ground improvement part 4 and the water stop zone 5, so that the shield excavator 1 is opened. Water does not flow from the point toward the inside.

  And since such a removal operation can be implemented without constructing a reaching shaft, the construction cost and the construction period can be reduced. In addition, the load on the surrounding environment can be minimized.

  For example, while the construction period for construction of the reaching shaft is 12 months, the underground continuous wall 3 can be shortened to 3 months. In addition, if the reaching shaft is constructed, a large amount of excavated soil is generated compared to the case where the underground continuous wall 3 is constructed. Furthermore, when the reaching shaft is constructed, noise and smoke generated when the shield excavator 1 is disassembled spreads to the ground, but if the underground continuous wall 3 is used, the smoke does not rise to the ground.

  Further, by setting the thickness of the wall body zone 30 to be equal to or longer than the length L from the cutter face 11 to the partition wall 13, the tunnel 10 from which the cutter face 11 has been removed can be stably maintained.

  Furthermore, since the tip of the tunnel 10 is supported by the highly rigid underground continuous wall 3, the occurrence of subsidence can be suppressed.

  Next, a method for removing the shield excavator 1 in a form different from the above embodiment will be described with reference to FIG. The description of the same or equivalent parts as those described in the above embodiment will be given the same reference numerals.

  In this example, as described in the above embodiment, the shield excavator 1 is inserted into the underground continuous wall 3A and then connected to the shield excavator 1A excavated from the opposite side toward the underground continuous wall 3A. The case where it is made to explain is demonstrated.

  In this embodiment, the ground improvement portions 4 and 4A and the water stop zones 5 and 5A are respectively constructed on both sides of the underground continuous wall 3A. That is, the ground improvement part 4A and the water stop zone 5A are constructed also in the ground G on the side where the other shield excavator 1A reaches.

  In addition, the timing for reaching the shield excavator 1A to the underground continuous wall 3A may be any timing before or after the timing for reaching the shield excavator 1 or almost at the same time. In this embodiment, the case where the shield excavator 1A is reached later will be described.

  The thickness B of the underground continuous wall 3A should be longer than the length L from the front surface of the cutter face 11 (the tip of the fishtail 11a) to the partition wall 13 of the two shield excavators 1 and 1A. That's fine. That is, if the two shield excavators 1 and 1A have the same size, the length may be at least twice the length L from the front surface of the cutter face 11 to the partition wall 13.

  Then, as shown in FIG. 6, the shield excavator 1 </ b> A is advanced toward the opening at the tip of the tunnel 10 formed by the shield excavator 1. This shield excavator 1A penetrates the water stop zone 5A, penetrates the ground improvement part 4A, and reaches the underground continuous wall 3A.

  When the shield excavator 1A arrives, the cutter face 11 and the partition wall 13 of the shield excavator 1 that have reached in advance have already been removed, and the tip of the tunnel 10 is in an open state.

  Therefore, inside the underground continuous wall 3A, the shield excavator 1A is connected to the opening of the tunnel 10 to penetrate the two tunnels. Since this connection is made only by aligning the position of the shield excavator 1A with the opening formed in the underground continuous wall 3, even if there is some construction error, it can be easily connected.

  Further, since the two shield excavators 1 and 1A are not directly joined in the ground, the shield excavator 1 and 1A having a normal structure can be used, and the cost can be reduced.

  Further, regardless of the progress of the shield excavator 1A to be connected, the shield excavator 1 can be removed when the planned arrival position is reached. For this reason, the construction of the tunnel 10 by the shield excavator 1 can be completed without waiting for the arrival of the shield excavator 1A. Further, if even part of the tunnel 10 can be completed at an early stage, it can be effectively utilized such as starting partial service.

  Furthermore, since the tip of the tunnel 10 is supported by the rigid underground continuous wall 3A, even when the tunnel is designed to be stabilized by integration, the completion of the connection with the shield excavator 1A is awaited. Even without it, the occurrence of subsidence can be suppressed.

  Other configurations and operational effects are substantially the same as those in the above-described embodiment, and thus description thereof is omitted.

  The embodiment of the present invention has been described in detail above with reference to the drawings. However, the specific configuration is not limited to the embodiment and the example, and the design change is within a range not departing from the gist of the present invention. Are included in the present invention.

  For example, in the said embodiment and Example, although the wall body zone 30 (30A) was comprised by the underground continuous wall 3 (3A) and the ground improvement part 4 (4, 4A), it is not limited to this. Instead, it may be a wall body zone constituted only by the underground continuous wall 3 (3A).

  Moreover, in the said embodiment and Example, although the underground continuous wall 3 (3A) of the reinforced concrete structure was demonstrated, it is not limited to this, The underground continuous wall of the unreinforced concrete structure in which a reinforcing bar is not arrange | positioned It may be. Furthermore, the structure which replaced the part which penetrates the shield excavator 1 with the material which is easy to cut with the cutter bit 11b may be sufficient. For example, it can be replaced with a synthetic resin material in which a plastic foam is reinforced with long glass fibers or the like, or a new material concrete that is easy to cut.

  Furthermore, in the said embodiment and Example, although the ground improvement part 4 (4A) was constructed adjacent to the underground continuous wall 3 (3A), it is not limited to this, The ground improvement part 4 (4A) It is also possible to construct a muddy water solidified wall on the ground G on the side where the shield excavator 1 of the underground continuous wall 3 (3A) reaches. In this case, a wall zone is formed by the underground continuous wall 3 (3A) and the muddy water solidified wall adjacent thereto.

  Moreover, in the said embodiment and Example, only the thickness B of the underground continuous wall 3 is the length L or more (or 2L or more) from the front surface (fishtail 11a tip) of the cutter face 11 to the partition wall 13. However, the thickness of the wall zone 30 (30A) including the underground continuous wall 3 (3A) and the ground improvement portion 4 (4, 4A) is not limited to this. The length from the front surface of 11 to the partition wall 13 may be a length L or more (or 2L or more).

  Furthermore, the removal method of the shield excavator 1 of this invention can be utilized also when connecting the tunnel 10 constructed | assembled by the shield excavator 1 to the existing underground structure. That is, the underground continuous wall 3 is constructed adjacent to the existing underground structure, and the shield excavator 1 reaches the underground continuous wall 3 and then communicates with the interior of the existing underground structure. Can do. By doing so, even if the existing underground structure does not have sufficient strength for reasons such as aging, the influence on the existing underground structure can be minimized and Can be linked.

1, 1A Shield excavator 3, 3A Continuous wall 30, 30A Wall zone 4, 4A Ground improvement part 5, 5A Water stop zone 11 Cutter face 13 Bulkhead G Ground

Claims (3)

A method for removing a shield excavator that dismantles and removes at least part of a shield excavator that has been dug into the ground,
A step of constructing a wall zone having the shield ground to the excavation of the arrival position of the excavator excavating, underground continuous wall of reinforced concrete structures by inserting the reinforcing bar cage,
Forming a water stop zone in the ground on the side where the shield excavator reaches the wall zone;
Penetrating the cutter face on the front side of the shield excavator into the underground continuous wall;
And a step of removal by removing the interior of the partition walls of the Kattafu E chair and the shield excavator from the shield excavator,
The method of removing a shield excavator, wherein a thickness of the wall zone that is in the same direction as an axial direction of the shield excavator at the time of penetration is equal to or greater than a length from the cutter face to the bulkhead .   The method for removing a shield excavator according to claim 1, wherein a ground improvement part or a muddy water solidified wall is constructed on the ground adjacent to the underground continuous wall as the wall body zone. The method for removing a shield excavator according to claim 1 or 2 , wherein the thickness of the wall zone is at least twice the length from the cutter face to the partition wall.

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