JP4679969B2 - Tunnel excavation method and shield machine - Google Patents

Description

  The present invention relates to a tunnel excavation method suitable for excavating a natural ground having a high adhesive strength and geological formation, and a shield machine for accurately carrying out the excavation method.

  Conventionally, mud pressure shields excavate natural ground with a cutter, add bentonite, CMC, and polymer additives to the excavated soil, mix them into plastic fluidized mud, and fill the chamber with this mud. Then, the muddy earth pressure in the chamber is used to dig while suppressing the face.

  By the way, when the ground is a soil having high adhesive strength such as consolidated clay or consolidated silt, the additive and the excavated soil are not easily mixed and may be consolidated in the cutter or the chamber. When excavated soil with high adhesive strength adheres and solidifies in the cutter or chamber, the excavation speed decreases and the excavation efficiency deteriorates.

  Therefore, in the case where the ground is a soil having a high adhesive strength, conventionally, an attempt has been made to improve the fluidity by adding a viscosity reducing material to the excavated soil and mixing the excavated soil and the viscosity reducing material.

  However, there has been a problem that the effect of the added viscosity reducing material is slow and is not always effective.

Patent documents relating to this type of tunnel excavation technology include the following.
Japanese Patent No. 3150298

  The present invention has been made in view of the above circumstances, and the object of the present invention is to reduce viscosity and promote fluidity of excavated soil even in a geological field where the geology and strata have high adhesive strength. The object of the present invention is to provide a tunnel excavation method capable of preventing sticking and consolidation.

  Another object of the present invention is to more effectively prevent excavation soil from sticking / consolidating, and when excavation soil adheres / consolidates to the back of the cutter or the corner of the chamber, An object of the present invention is to provide a tunnel excavation method that can eliminate this.

  Another object of the present invention is to provide a tunnel excavation method that allows excavation while suppressing the face more stably.

  Furthermore, the other object of this invention is to provide the tunnel excavation method which can discharge | emit the excavation soil in a chamber efficiently.

  Still another object of the present invention is to provide a shield machine that can accurately carry out the method of the present invention.

To achieve the above object, in the first aspect of the present invention of the present invention, the shield machine 1 Te excavation method smell tunnel boring a tunnel, the front and the working face surface of the cutter 5 provided at least on the shield machine 1 In the meantime, a mixture of mud material and air pumped by the mud material pump pump unit 33 is fed , and fine sand, shirasu and pearlite are fed into the excavated soil taken into the chamber 16 formed in the shield machine 1. , A mixture of a modifier and a mud clay material consisting of at least one of lightweight aggregate, urethane foam beads, urethane foam strips, plant strips, fibers, rice husks, wood chips, sawdust, zeolite and husks or wherein a mixture of modifiers and viscosity lowering material added is pumped by a mixture pressure pump unit 24, kneading and the excavated soil, and the added said mixture Ze, so that go with boring a tunnel to suppress the working face 42 by the pressure of the mud that is created by mixing kneaded and the mixture with the excavated soil.
In order to achieve the above object, in the invention according to claim 2 of the present invention, in the excavation method, air is singly or a mixture of the modifying material and the mud clay material or the It is mixed with a mixture of a modifier and a viscosity reducing material and fed.
In order to achieve the above object, in the invention according to claim 3 of the present invention, in the excavation method, air alone or in the modifying material is disposed in the earth removing device 17 provided in the shield machine 1. And mixed with the mixture of the mud and clay material or the mixture of the modifying material and the viscosity reducing material.
In order to achieve the above object, in the invention according to claim 4 of the present invention, in the shield machine, a plurality of air / mud clay material discharge holes 20a are provided at least in front of the cutter 5, and the cutter rotating shaft is provided. The swivel joint 22 is attached to the rear end of the air swirl joint 22, and the air / mud clay material discharge hole 20a is provided over the cutter rotating shaft 7 and the inside of the cutter pork 9. 21, a mud clay material feed pump unit 33 and an air compressor 27 are installed in or behind the shield cylinder 2, and the air / mud clay material pipe 21 is connected to the air compressor 27 and the swivel joint 22. Connected to the mud clay pressure feed pump unit 33, the partition 3 is provided with a mixture discharge pipe 18 opened in the chamber 16, Inside or behind the cylinder 2 of fine sand, shirasu, pearlite, lightweight aggregate, foamed urethane beads, foamed urethane strips, plant strips, fibers, chaff, wood chips, sawdust, zeolite and oyster shells A mixture pressure feed pump unit 24 for feeding a mixture of at least one of a modifier and a mud clay material or a mixture of the modifier and a viscosity reducing material is provided separately from the mud clay material pressure feed pump unit 33, and the mixture discharge The pipe 18 and the mixture pumping pump unit 24 are connected by a mixture pipe 26.
In order to achieve the above object, in the invention according to claim 5 of the present invention, in the shield machine, an air discharge pipe 19 is provided in the partition wall 3 so as to open into the chamber 16. The air compressor 27 is connected to the air pipes 29 and 31 and air is mixed into the chamber 16 alone, or mixed with the mixture of the modifying material and the mud clay material or the mixture of the modifying material and the viscosity reducing material. Piping is possible to pump.
In order to achieve the above object, in the invention according to claim 6 of the present invention, in the shield machine, an air / mixture discharge pipe 23 is provided in the soil removal device 17, and the air / mixture discharge pipe 23 is discharged. In the earth device 17, air is singly or mixed with the mixture of the modifying material and the mud clay material or the mixture of the modifying material and the viscosity reducing material so as to be pressure-feedable.

According to the first aspect of the present invention, the mud clay material or the viscosity reducing material adheres around the particles or strips of the modifying material, and the adhesion between the excavated soil in the chamber 16 by these deposits. Can be reduced, that is, the viscosity can be reduced. As a result, there is an effect that can effectively prevent the excavated soil from adhering and solidifying even in a soil having a high adhesive strength and strata, and the pressure of the mud with fluidity in the chamber 16 is effective. As a result, the face 42 can be stably suppressed and the tunnel can be efficiently dug. In addition, since the mixture of air and mud material is sent between the front surface and the face of the cutter 5, the mixture of air and mud material is immediately added to the excavated soil, and it is excavated by stirring with a cutter bit. It can prevent mud soil with fluidity by preventing sticking and consolidation of soils. Therefore, there is an effect that the tunnel can be dug while the face 42 is more stably suppressed by the pressure of the mud having fluidity.
According to the invention described in claim 2 of the present invention, air and a mixture of a modifier and a mud clay material or a mixture of a modifier and a viscosity reducing material are added to the excavated soil in the chamber 16 and kneaded. When mixed, the adhesion between the excavated soil can be more effectively reduced by the synergistic action of the added mixture and air, so that the excavated soil in the chamber 16 can be more firmly fixed and consolidated. There is an effect that can be prevented more accurately. Further, by blowing air alone into the chamber 16, there is an effect that the excavated soil fixed and consolidated to the rear surface of the cutter 5, the corner portion of the chamber 16, and the like can be removed.
Further, according to the third aspect of the present invention, when air is sent alone into the soil removal device 17, the excavated soil is fixed and consolidated into the soil removal device 17 by the action of the air. In the case where the above mixture is mixed with air and fed into the earth removing device 17, friction resistance is generated in the earth excavating soil in the earth removing device 17, and the earth excavating soil in the earth removing device 17 is removed. Can be prevented. Therefore, in any case, there is an effect that the soil can be efficiently discharged.
Further, according to the fourth aspect of the present invention, there is an effect that the excavation method according to the first aspect can be accurately performed.
Further, according to the fifth aspect of the present invention, there is an effect that the excavation method according to the second aspect can be accurately performed.
Furthermore, according to the sixth aspect of the present invention, there is an effect that the excavation method according to the third aspect can be accurately performed.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a system diagram of a shield machine for carrying out the excavation method according to the present invention.

  The shield machine 1 of the embodiment shown in FIG. 1 includes a shield cylinder 2, a partition wall 3, a hood 4, a cutter 5, a cutter drive device 13, a drilling soil chamber 16, a soil removal device 17, and a shield. Jack (not shown), mixture discharge pipe 18, air discharge pipe 19, air / mud clay material discharge holes 20a, 20b, swivel joint 22, mixture pressure feed pump unit 24, air compressor 27, mud clay The material pressure feed pump unit 33 is provided.

  The cutter 5 includes a cutter rotating shaft 7 rotatably supported on the partition wall 3 via a bearing 6, a cutter pork 9 attached to a front end portion of the cutter rotating shaft 7 via a boss 8, and the cutter pork. 9 has a fish tail bit 10 provided on the center front surface, a plurality of cutter bits 11 provided on the front surface of the cutter pork 9, and a plurality of stirring blades 12 attached to the back surface of the cutter pork 9. .

  The cutter driving device 13 includes a gear box 14 fixed to the back surface of the partition wall 3, a rotation driving source 15 such as an electric motor attached thereto, and a rotation driving source 15 provided inside the gear box 14. And a reduction gear (not shown) that transmits the speed to the cutter rotating shaft 7.

  The chamber 16 is formed in a space surrounded by the partition wall 3, the hood 4, and the cutter pork 9.

  In this embodiment, a screw conveyor is used for the earth removing device 17.

  A plurality of shield jacks are installed inside the shield tube 2 at a predetermined interval. And this shield jack takes reaction force in the segment 43 of the front row, and pushes the shield machine 1.

  The distal ends of the mixture discharge pipe 18 and the air discharge pipe 19 are attached to the partition wall 3 so as to open to the chamber 16.

  Of the air / mud clay material discharge holes 20a, 20b, one air / mud clay material discharge hole 20a is provided by opening from the inside of the cutter pork 9 to the front surface of the cutter 5, that is, the face 42 side. ing. The other air / mud clay material discharge hole 20b is provided in a plural number by being opened from the inside of the cutter pork 9 toward the back surface of the cutter 5, that is, toward the chamber 16. In addition, you may make it open also to the side surface of the cutter 5. FIG.

  The swivel joint 22 is attached to the rear end portion of the cutter rotating shaft 7.

  The air / mud clay material discharge holes 20a, 20b and the swivel joint 22 are connected to each other by an air / mud clay material pipe 21 provided inside the cutter pork 9 through the cutter rotating shaft 7 and the boss 8.

  An air / mixture discharge pipe 23 is provided on the front end side of the casing of the earth removing device 17.

  The mixture pumping pump unit 24, the air compressor 27, and the mud clay material pumping pump unit 33 are installed behind the shield cylinder 2 in the illustrated embodiment, but may be installed inside the shield cylinder 2.

  The mixture discharge pipe 18 is connected to a mixture pressure pump unit 24 via a distributor 25 and a mixture pipe 26.

  The air discharge pipe 19 is connected to an air compressor 27 via a distributor 28, an air pipe 29, a distributor 30 and an air pipe 31.

  In the illustrated embodiment, air is supplied from the distributor 30 to the mixture discharge pipe 18 via the air pipe 32. However, air may be supplied from the distributor 30 to the mixture pipe 26. good.

  The swivel joint 22 is connected to a mud clay material feed pump unit 33 via a mud clay material pipe 34. The swivel joint 22 is connected to the air compressor 27 via a distributor 28, an air pipe 35, distributors 36 and 37, and an air pipe 38.

  Further, an air compressor 27 is connected to the middle of the mud material pipe 34 connecting the swivel joint 22 and the mud material pressure feed pump 33 via a distributor 28, an air pipe 35, distributors 36 and 37, and an air pipe 39. Has been.

  The air / mixture discharge pipe 23 provided in the earth removing device 17 is connected to an air compressor 27 via a distributor 28, an air pipe 35, a distributor 36 and an air pipe 40.

  In the middle of the air pipe 40, a mixture pressure pump unit 24 is connected via a distributor 25 and a mixture pipe 41.

  A tail seal 44 that is in contact with the outer peripheral surface of the segment 43 is attached to the rear end portion of the shield tube 2.

  The partition wall 3 is provided with a soil pressure gauge (not shown) facing the chamber 16.

  Next, an example of the excavation method of the present invention will be described in relation to the operation of the shield machine 1.

  First, a modifying material, a mud clay material, a viscosity reducing material, and the like are charged into the tank of the mixture pressure pump unit 24.

The modifier, for example fine sand, Shirasu, pearlite, lightweight aggregate, foamed polyurethane beads and the strip, vegetable strips, fibers, rice hulls, wood chips, sawdust, zeolites, alone or with oyster shells, etc. Mix seeds and use.

  As the mud material, a thin bentonite solution, an aqueous solution of a polymer-based mud material, or the like may be used for consolidated clay or dotan.

  Alternatively, a viscosity reducing material may be used. Examples of the viscosity reducing material include bentonite, CMC, and polymeric additives. Further, a mixed solution such as a foam material and a bentonite solution may be used.

  The mixture of the modifying material and the mud clay material or the viscosity reducing material is used by mixing the modifying material with a solution of the mud clay material or the viscosity reducing material to give fluidity.

  In addition, the mud material is put in the tank of the mud material pump pump unit 33.

  In excavating the face 42, the cutter driving device 13 is driven, the entire cutter 5 is rotated via the cutter rotating shaft 7, and the face 42 is excavated by the cutter bit 11.

  Simultaneously with the start of excavation of the face 42, the shield jack is extended by applying a reaction force to the fixed member installed behind the shield cylinder 2 or the segment 43 assembled in advance, and thrust is applied to the entire shield machine 1 for excavation. Go.

  At this time, the excavated soil of the face 42 is taken into the chamber 16. Then, a mixture of the modifying material, the mud clay material, and the viscosity reducing material is added to the excavated soil taken into the chamber 16 through the distributor 25, the mixture pipe 26, and the mixture discharge pipe 18 from the mixture pumping pump unit 24.

  In addition, air is sent from the air compressor 27 to the excavated soil in the chamber 16 through the distributor 28, the air pipe 29, the distributor 30, the air pipe 31, and the air discharge pipe 19, and if necessary, the distributor 30 and the air pipe. Through 32, air is also sent to the mixture discharge pipe 18, and air is mixed and sent to the excavated soil in the chamber 16 to the mixture of the modifier, the mud clay material, and the viscosity reducing material.

  Further, the mud material pipe 34 and the swivel joint material 22 are sent to the excavated soil in the chamber 16 from the mud material pressure feed pump unit 33, and the distributor 28, the air pipe 35, and the distributor are supplied from the air compressor 27. Air is sent to the mud clay pipe 34 through the vessels 36 and 37 and the air pipe 39. Then, the mixture of the air and the mud material is fed into the gap between the front surface and the face surface of the cutter 5 through the swivel joint 22, the air / mud material pipe 21 and the air / mud material discharge holes 20a. Furthermore, a mixture of air and the mud clay material is fed into the excavated soil in the chamber 16 through the air / mud clay material pipe 21 and the air / mud clay material discharge hole 20b.

  Then, the excavated soil in the chamber 16, the mixture of the reforming material, the mud clay material, the viscosity reducing material, and the air sent into the chamber 16 from the mixture discharge pipe 18, and the air discharge pipe 19 sent into the chamber 16. A plurality of agitation blades 12 attached to the back surface of the cutter pork 9, and a mixture of air and mud material sent into the chamber 16 from the air / mud material discharge hole 20 b, Knead with the stirring action. As a result, even if the excavated soil taken into the chamber 16 is a soil having high adhesive strength such as consolidated clay or consolidated silt, mud-soil material or viscosity reducing material adheres around the reforming material. Furthermore, since air is present around the reforming material, the adhesion between the excavated soils in the chamber 16 can be effectively reduced, and since mixed air is also present, It is possible to accurately prevent the excavated soil from sticking and consolidation. It is also possible to prevent the excavated soil from sticking to the corners of the cutter pork 9 and the hood 4. As a result, even if the soil and stratum with high adhesive strength are dominant, the excavated soil is converted into mud with plastic fluidity, and the pressure of the mud with plastic fluid in the chamber 16 The face 42 can be stably suppressed.

  Furthermore, the excavated soil of the face 42 and the mixture of air and mud soil material sent between the front surface and the face of the cutter 5 are agitated by a number of cutter bits 11. Thereby, the excavated soil accumulated between the front surface and the face of the cutter 5 can also be converted into mud that has been fluidized plastically, and the face 42 can be stably suppressed by the pressure of the mud.

  As described above, since the face 42 can be stably suppressed by the pressure of the plastic fluidized mud, the excavation efficiency can be improved.

  Then, after excavating the face 42 within a predetermined range, the entire shield machine 1 is propelled by the shield jack while the earth pressure in the chamber 16 is monitored by the earth pressure gauge.

  Next, after the shield machine 1 is propelled for a predetermined distance, the shield jack is reduced and the segment 43 is assembled behind the shield cylinder 2.

  While maintaining the inside of the chamber 16 at a predetermined earth pressure, the excavating soil in the chamber 16 is taken in by the earth removing device 17 along with the excavation, and the excavating soil is carried out behind the shield tube 2.

  In general, when excavated soil is fixed and consolidated in the soil removal device, the soil removal efficiency decreases. Also, when excavated soil is provided in the soil removal device, the soil removal efficiency is reduced.

  Therefore, in this embodiment, air is sent alone or mixed with the mixture of the modifying material, the mud clay material, and the viscosity reducing material through the air / mixture discharge pipe 23 provided on the front end side of the casing of the earth removing device 17. I have to.

  As described above, by sending air into the soil removal device 17, the excavated soil can be prevented from being fixed and consolidated in the soil removal device 17, and the soil removal efficiency can be improved. Moreover, by mixing and feeding air into the mixture of the modifying material, the mud clay material, and the viscosity reducing material into the soil removal device 17, the soil is discharged to the excavated soil in the soil removal device 17 by the function of the property modification material. A frictional force is applied to the inside of the casing of the device 17, and a frictional resistance is generated by this frictional force, thereby preventing a surrounding phenomenon in the soil removal device 17 and improving the soil removal efficiency.

  By the way, when excavation soil adheres to and solidifies on the back surface of the cutter 5, the corner portion in the chamber 16, or the like, the excavation efficiency decreases.

Therefore, in this embodiment, air is blown through the air discharge pipe 19 provided in the partition wall 3 and the air / mud clay material discharge hole 20b provided in the back surface of the cutter 5. Thereby, the excavated soil fixed and consolidated to the back surface of the cutter 5 or the corners in the chamber 16 can be removed. As a result, the excavation efficiency can be improved.

An example of the shield machine for enforcing the excavation method of this invention is shown, and it is the systematic diagram which showed a part in cross section.

DESCRIPTION OF SYMBOLS 1 Shield machine 2 Shield cylinder 3 Bulkhead 4 Hood 5 Cutter 7 Cutter rotation shaft 9 Cutspoke 11 Cutter bit 12 Stirring blade 13 Cutter drive device 16 Chamber 17 Soil discharge device 18 Mixture discharge pipe 19 Air discharge pipe 20a, 20b Air / mud clay Material discharge hole 21 Air / mud clay material piping 22 Swivel joint 23 Air / mixture discharge tube 24 Mixture pressure feed pump unit 26 Mixture piping 27 Air compressor 29 , 3 1, 32 Air piping 33 Mud soil material pressure feed pump unit 34 Mud soil material piping 35 , 38 , 39 , 40 Air piping 41 Mixture piping 42 Faces 43 Segments

Claims (6)

A tunnel excavation method for excavating a tunnel with a shield machine (1),
At least between the front surface and the face of the cutter (5) provided in the shield machine (1), a mixture of mud material and air pumped by the mud material pump pump unit (33) is sent,
In the excavated soil taken into the chamber (16) formed in the shield machine (1), fine sand, shirasu, perlite, lightweight aggregate, foamed urethane beads, foamed urethane strips, plant strips, fibers, fir tree The mixture of the modified material and the mud clay material or the mixture of the modified material and the viscosity reducing material made of at least one of wood chips, sawdust, zeolite, and chaff is pumped by the mixture pumping pump unit (24). It added Te,
Kneading the excavated soil and the added mixture,
Going to boring a tunnel by suppressing the working face (42) by the pressure of mud created by mixing kneaded and the mixture with the excavated soil,
A tunnel excavation method characterized by this. In the chamber (16), alone air, or according to claim 1, characterized in that the mixture of modifiers and created mud material or mixed to a mixture of the modifier and viscosity lowering material, fed Tunnel excavation method. In the earth removing device (17) arranged in the shield machine (1) , air is mixed alone or mixed with the mixture of the modifying material and the mud clay material or the mixture of the modifying material and the viscosity reducing material, The tunnel excavation method according to claim 1, wherein the tunnel is dug. A plurality of air / mud clay material discharge holes (20a) are provided at least in front of the cutter (5),
Attach the swivel joint (22) to the rear end of the cutter rotation shaft (7),
The swivel joint (22) and the air / mud clay material discharge hole (20a) are connected by an air / mud clay material pipe (21) provided inside the cutter rotating shaft (7) and the cutter pork (9). ,
Install the mud clay pressure pump unit (33) and the air compressor (27) inside or behind the shield tube (2),
The air / mud clay pipe (21) is connected to the air compressor (27) and the mud clay pressure feed pump unit (33) via a swivel joint (22),
The partition wall (3) is provided with a mixture discharge pipe (18) opened in the chamber (16),
Inside or behind the shield tube (2), fine sand, shirasu, pearlite, lightweight aggregate, foamed urethane beads, foamed urethane strips, plant strips, fibers, chaff, wood chips, sawdust, zeolite and oyster shells A mixture pressure feed pump unit (24) for feeding a mixture of the reforming material and the mud clay material or the mixture of the reforming material and the viscosity reducing material consisting of at least one of the above, and the mud clay material pressure feed pump unit (33). Separately,
The mixture discharge pipe (18) and the mixture pumping pump unit (24) were connected by a mixture pipe (26).
Shield machine characterized by that. The partition wall (3 ) is provided with an air discharge pipe (19) opened in the chamber (16),
The air discharge pipe (19) and the air compressor (27) are connected by air pipes (29, 31), and air is supplied into the chamber (16) alone, or the reformer and mud material Mixed with the mixture or the mixture of the modifier and viscosity reducing material, and piped so as to be pumped.
The shielding machine according to claim 4 . The soil removal device (17) is provided with an air / mixture discharge pipe (23),
The air / mixture discharge pipe (23) is mixed with air alone in the soil removal device (17), or mixed with the mixture of the modifying material and the mud clay material or the mixture of the modifying material and the viscosity reducing material. Piped for pumping,
The shielding machine according to claim 4 or 5, wherein

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