JP5503218B2 - Backing prevention device when starting shield machine - Google Patents

Description

  The present invention relates to an apparatus for preventing backing when starting a shield machine.

  In shield construction, when a shield machine is started from a start shaft, in the case of a small / medium caliber machine, the shield machine is often assembled in a natural ground and carried directly into the shaft using a crane or the like. However, in the case of a large depth or a large cross section (large diameter), it is often divided into a shaft and assembled in the shaft. In that case, when the shaft is sufficiently large and there is a space for assembling the entire machine under the shaft, the machine is started after the entire machine is assembled.

  However, when the size of the start shaft cannot be sufficiently secured due to the limitation of the space at the start base and the existing structure, especially when a long shaft cannot be constructed with respect to the start direction, the machine is divided and assembled. Split start is required. However, in the case of large sections and depths, the soil water pressure that the machine receives on the front face of the face becomes very large. Therefore, first assemble the front torso, start with only the front torso, and when the front torso enters the ground, fix the front torso, then assemble the middle torso, and then attach the middle torso Then, fix the middle torso, and finally assemble the rear torso.After the assembly is completed, press the back reaction force or temporary segment with the shield jack of the shield machine to move the entire length of the machine to the ground. Push in. After that, the temporary segment is set up in the vertical shaft in the same way as a normal shield machine. In this series of starting steps, it is possible to minimize the length of the shaft by pushing it into the ground for every assembly with the front trunk, middle trunk, and rear trunk.

  However, in the starting process of the shield machine, there is a possibility that the shield machine will be backed (returned back) because it receives a large earth water pressure from the front. Therefore, conventionally, in order to prevent the shielding machine from backing, for example, as described in Patent Document 1, a penetration pin or a friction plate penetrating into the ground can be protruded radially on the outer shell outer periphery of the shielding machine. Have been proposed (the former), and the wall of the shaft and the rear part of the shield machine are connected by a connecting member such as a wire or a turnbuckle (the latter).

JP 2003-193792 A

  However, in the former case, the structure of the shield machine has to be complicated, and in the latter case, there is a problem that much labor is required to attach and remove the connecting member.

  The present invention has been made in view of the above circumstances, and provides a backing prevention device at the start of a shielding machine that can prevent the shielding machine from backing without complicating the structure of the shielding machine or requiring labor. The purpose is to do.

In order to achieve the above-mentioned object, the present invention is an apparatus for preventing a shield machine from backing due to earth and water pressure in a natural ground when starting the shield machine from a vertical shaft in a natural ground, and is fixed to the start port of the vertical shaft. A fixed portion, a floating plate disposed in the vicinity of the fixed portion, and a pin driving jack for inserting and removing a taper pin into a pin hole formed in the floating plate and formed in a shield machine or a steel shell connected to the shield machine , wherein the fixing unit floating plate connecting the, after the stretch-free and is and the taper pin is inserted into the pin hole when the pin is inserted into the pin holes is an elastic fixing the position of the floating plate and a position adjusting jack can be adjusted, the floating plate, said shield machine is formed in a square cross section 4 are formed corresponding to each surface of the steel shell, and a plurality of the pin drives for inserting / removing the taper pins into / from the plurality of pin holes formed in a horizontal row on each surface of each floating plate. A jack is provided, a pair of the position adjusting jacks are provided between the fixed portion and each of the floating plates, and the taper pin is provided so as to be swingable in a lateral direction with respect to the pin driving jack. It is a feature.

  ADVANTAGE OF THE INVENTION According to this invention, the backing of a shield machine can be prevented, without requiring the complexity of the structure of a shield machine and an effort.

It is a figure showing roughly the first process of starting a shield machine from a shaft in an embodiment of the present invention. It is a figure which shows schematically the next process of starting a shield machine. It is a figure which shows schematically the next process of starting a shield machine. It is sectional drawing which shows an example of a shield machine. It is a front view of the shield machine. It is a figure which shows an example of a backing prevention apparatus. It is a top view of the backing prevention apparatus. It is an AA line expanded sectional view of FIG.

  EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is explained in full detail based on an accompanying drawing.

  In FIG. 1 to FIG. 3, reference numeral 1 denotes a vertical shaft (also referred to as a start vertical shaft) provided in a natural ground, and a shield machine 2 is carried into the lower portion of the vertical shaft 1 from above by a crane or the like. . The vertical shaft 1 is provided with a frame 1a that forms an inner wall thereof. In this embodiment, a center hole jack 3 is used as a driving means for starting the shield machine 2 from the shaft 1 into the ground. In the shaft 1, a total of four reaction force columns 4 are installed on the front and rear housings 1a via the supporting walls 5a and 5b so as to surround the shield machine 2 along the starting direction. A movable back anchor girder 7 for extruding 2 directly or indirectly through a steel shell 6 is supported so as to be movable along the reaction force column 4.

  One end of a PC steel wire 8 is fixed to the front end side of each reaction force support column 4, and the back anchor girder 7 is fed forward by pulling the PC steel wire 8 to the back anchor girder 7 by expansion and contraction and a wedge member. A center hole jack 3 is provided. In the case of a propulsion method in which a steel shell 6 is connected to the rear end of the shield machine 2 to start from the shaft 1, a push jack (not shown) is generally used as a driving means for starting.

The shaft 1 is provided with a backing prevention device 10 that prevents the shield machine 2 from backing due to soil water pressure in the natural ground when the shield machine 2 is started from the ground shaft 1. The backing prevention device 10 includes a fixed portion 11 fixed to the start port 1h of the shaft 1, a floating plate 12 disposed in the vicinity of the fixed portion 11, and the shield machine 2 or the shield provided on the floating plate 12. A pin drive jack 15 for inserting / removing a taper pin 14 into / from a pin hole 13 formed in a steel shell 6 connected to the machine 2, a fixed portion 11 and a floating plate 12 are connected, and the taper pin 14 is inserted into the pin hole 13. A position adjustment jack 16 that is sometimes free from expansion and contraction and is fixed to expand and contract after the taper pin 14 is inserted into the pin hole 13 and can adjust the position of the floating plate 12 is provided.

  As shown in FIGS. 6 to 8, the floating plate 12 is formed corresponding to each surface of the shield machine 2 or the steel shell 6 having a square cross section, and each floating plate 12 has a row on each surface. A plurality of pin drive jacks 15 are provided to insert and remove the taper pins 14 with respect to the plurality of pin holes 13 formed in the above. 1 to 3 show only the upper buckling device 10.

  A pair of the position adjustment jacks 16 is provided between the fixed portion 11 and each floating plate 12 so that the floating plate 12 can be moved and adjusted along the axial direction of the shield machine 2. The fixing portion 11 includes a plurality of (four in the illustrated example) fixing brackets 11a provided directly on the housing 1a or indirectly via the bearing wall 5a, and the housing 1a and the shield machine 2 or the steel shell at the start opening 1h. 6 and an entrance seal 17 that seals between the two. The entrance seal 17 is formed so as to surround the outer periphery of the shield machine 2 or the steel shell 6. The distal end portion 11b of the fixed bracket 11a extends so as to suppress the upper surface of the floating plate 12.

  The position adjusting jack 16 and the pin drive jack 15 are, for example, hydraulic jacks or pneumatic jacks. One end of the position adjustment jack 16 is attached to the surface of the entrance seal 17 via a bracket 18a, and the other end of the position adjustment jack 16 is attached to the surface of the floating plate 12 via a bracket 18b. The front end portions 11b of the fixing brackets 11a at both ends in the width direction restrict the lateral movement of the floating plate 12 with a predetermined play and move a part of the lower surface of the floating plate 12 in the axial direction (X direction) of the shield machine 2. It has the support part 11c supported so that it is possible.

  The pin drive jack 15 is attached to the surface of the floating plate 12 vertically (Z direction) via a bracket 19. The taper pin 14 is provided so as to be swingable in a predetermined range in the lateral direction (Y direction) by a pin joint 20 with respect to the pin drive jack 15. The floating plate 12 is provided with a guide 21 that supports the taper pin 14 so as to be able to swing in a predetermined range in the lateral direction. A pin hole 13 is provided at a position corresponding to the taper pin 14 in the shield machine 2 or the steel shell 6. These pin holes 13 may be taper holes so as to correspond to the taper pins 14, but may be normal holes or bolt holes into which eyebolts or the like are screwed.

  On the other hand, the shield machine 2 includes an outer cylinder 23 having a rectangular cross section, an inner cylinder 24 having a circular section that is detachably accommodated in the outer cylinder 23, and an inner side that is provided at the front end of the inner cylinder 24 and closes the inner cylinder 24. A partition wall 25, a cutter device 26 provided in the inner partition wall 25 for excavating a front ground, an outer partition wall 27 provided at the front end of the outer cylinder 23 and closing the space between the outer cylinder 23 and the inner cylinder 24, and the inner partition wall 25 And a soil removal device 28 detachably provided. The outer cylinder 23 includes a front body portion 23a, a middle body portion 23b, and a rear body portion 23c.

  Next, the operation of the embodiment will be described. First, the case of starting while assembling the shield machine 2 will be described. A pin hole 13 corresponding to a taper pin of the backing preventing device is provided in advance in the front body portion 23a, the middle body portion 23b, and the rear body portion 23c. When the pin hole 13 of the front body portion 23 a comes within the movable range of the taper pin 14 of the backing prevention device 10, the taper pin 14 is inserted into the pin hole 13 while being adjusted by the position adjustment jack 16 and the pin drive jack 15.

  Thereby, the backing movement of the front body portion 23a can be suppressed. In this state, the middle body portion 23b is assembled. After the assembly is completed, the back anchor girder 7 is brought into contact with the end portion of the middle barrel portion 23b, the taper pin 14 is pulled out from the pin hole 13, and the middle barrel portion 23b is pushed into the natural ground by the center hole jack 3 while excavating again. . When the pushing of the middle body part 23b is completed, the taper pin 14 is inserted into the pin hole 13 of the middle body part 23b again. The back anchor beam 7 is moved backward to assemble the rear trunk portion 23c.

  The entire shield machine is assembled as described above, and at that time, the middle torso part 23b is already in the ground, so that the back anchor girder 7 and the center hole jack 3 can be pushed into the ground. When the shield machine has a shield jack, excavation may be carried out using a temporary segment and a shield jack. Even in that case, since the length of the vertical shaft 1 in the front-rear direction is short, only a few temporary segments are required.

  On the other hand, in the propulsion method using a steel shell, the steel shell 6 is connected to the rear end of the rear body portion 23c of the shield machine, and the propulsion for one ring of the steel shell 6 is finished. When connecting in the shaft 1, it is necessary to pull back the main pushing jack from the pushed steel plate 6 and insert a new next steel shell. At this time, when the earth and water pressure applied to the front surface of the front end of the machine is large, a force is exerted to push the machine and all the assembled steel plates back into the shaft 1. If the lengths of the assembled steel shells are long enough, the steel shells will be balanced in the peripheral frictional force received from the natural ground, or if they exceed the force to push back, Will not be pushed back. However, when the excavation length is short and the peripheral surface frictional force cannot counter the face soil water pressure, that is, when there is no force or a shortage of the force to prevent the backing, the backing prevention device 10 is applied to the start opening 1h. The movement of pushing the steel shell 6 back into the shaft 1 is fixed. Then, a new steel shell is installed between the main jack and the steel shell is pushed forward by the main jack. This series of operations will be repeated to carry out the propulsion work.

For jacking method, the during insertion and withdrawal of the taper pin 14, the position adjusting jack 16 pin power jack 15, carried out while adjusting the extensor contraction free or small.

By using these two jacks in combination, the insertion position of the taper pin 14 can be adjusted in three axes in the X, Y, and Z directions or automatically using a taper. The position adjustment jack 16 can be adjusted in the X direction, the pin joint 20 of the taper pin 14 and the pin drive jack 15 in the Y direction, and the pin drive jack 15 in the Z direction. The taper pin 14 can be made of a material having a high strength such as a tempered SCM435 and an allowable shear stress of 226 N / mm ² .

  The actual operation for preventing backing is as follows. When the propulsion for one ring is completed, before the main jack is pulled back, the position of the taper pin in the X direction is set on each surface of the steel shell according to the pin hole of the steel shell. Align with the position adjustment jack 16 integrally. Thereafter, a plurality (three in the drawing) of taper pins 14 are inserted into the pin holes 13 by the pin drive jack 15. Even if the taper pin 14 is inclined, since the pin drive jack 15 and the taper pin 14 are held by the pin joint 20, the taper pin 14 is smoothly inserted into the pin hole 13. When the insertion is completed, pull back the push jack, insert a new steel shell 6, perform bolt fastening with the existing steel rod, and press the push jack against the new copper shell end face again to promote the next ring. Is ready. Stop the steel shell with a slight push on the steel shell. Next, the taper pin 14 is pulled out by the pin drive jack 15 while moving the pin drive jack 15 and the position adjustment jack 16 of the backing prevention device 10 slightly back and forth. Then proceed to the next ring propulsion.

  As is clear from the above description, according to the backing prevention apparatus at the start of the shield machine of the present embodiment, the shield machine can be prevented from backing without complicating the structure of the shield machine or requiring labor.

  The embodiments of the present invention have been described in detail with reference to the drawings. However, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the gist of the present invention. .

DESCRIPTION OF SYMBOLS 1 Shaft 2 Shielding machine 6 Steel shell 10 Backing prevention apparatus 11 Fixing part 12 Floating plate 13 Pin hole 15 Pin drive jack 16 Position adjustment jack

Claims (1)

A device that prevents the shield machine from backing due to earth and soil pressure when starting the shield machine from the ground shaft, and is disposed in the vicinity of the fixed portion that is fixed to the start port of the shaft. and the floating plate, and connecting the pin power jack to connect or disconnect the taper pin into the pin hole formed in the steel shell is connected to the shield machine or the shield machine is provided in the floating plate, the floating plate and said fixed portion, It said pin after said when it is inserted into the pin holes is expansion and contraction free and the taper pin is inserted into the pin holes is an elastic fixing, and a position adjusting jack capable positional adjustment of said floating plate,
Four floating plates are formed corresponding to each surface of the shield machine or the steel shell having a square cross section, and each floating plate has a plurality of pin holes formed in a horizontal row on each surface. A plurality of the pin drive jacks are provided to insert and remove the taper pins with respect to
A pair of the position adjustment jacks are provided between the fixed portion and each of the floating plates,
A backing prevention device when starting a shield machine , wherein the taper pin is provided so as to be swingable in a lateral direction with respect to the pin drive jack .

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