JP2012154107A - Mud pressure shield method and mud pressure shield system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mud pressure shield method which has a high recovery rate of additives.SOLUTION: A mud pressure shield method includes injecting additives into a cutter chamber 3 formed between a face and a partition wall 13 and kneads the additives with drilling mud. The additives contain a liquefaction component which is in a solid state at the facing temperature and liquefied at the liquefaction temperature higher than the facing temperature. The kneaded material of the additives and the drilling mud is discharged from the cutter chamber 3 and heated in a thermal separation part 21, so that the liquefaction component is liquefied to be separated from the kneaded material.

Description

  The present invention relates to a mud pressure shield method and a mud pressure shield system for constructing the mud pressure shield method.

  When excavating a tunnel or a pipe on the ground where the face is not self-supporting, a mud pressure shield method using a sealed shield machine is suitably performed.

  In this mud pressure shield method, water and additives are injected into the excavated soil, reformed into mud with plastic fluidity and water stopping properties, filled into the cutter chamber and screw conveyor, and the face and mud are separated. This is a method of excavating the ground in a pressure balanced state. Here, the mud from the cutter chamber needs to be disposed as industrial waste because the additive is injected. Therefore, it is desired to reduce the amount of discharged mud from the cutter chamber as much as possible.

  For example, Patent Document 1 describes a mud pressure shield method using mortar-shaped mud as an additive. In this construction method, the kneaded material from the cutter chamber is sent to a separation device to be separated into mud and excavated soil, and the excavated soil is discharged, while mud is supplied to the pressure chamber and reused.

  By using this method, the amount of industrial waste can be reduced by the amount of the separated mud. As a result, the area of a necessary yard (temporary storage place) can be reduced and the waste disposal cost can be suppressed.

JP 58-83795 A

  In the construction method of Patent Document 1 described above, since mortar-like mud is used as an additive, the mortar attached to crushed stone is hard to be separated and is hard to be separated, and the recovery rate of the additive that is separated and recovered by the separator is increased. There was a problem that was difficult.

  This invention is made | formed in view of such a situation, and it aims at raising the collection | recovery rate of an additive at the time of construction of a mud pressure shield construction method.

  In order to solve the above problems, the present invention provides a mud pressure shield method in which an additive is injected into a cutter chamber formed between a face and a partition wall and kneaded with excavated soil. Using a solid material that contains a liquefied component that is liquefied at a liquefaction temperature higher than the face temperature, the kneaded material of the additive and the excavated soil is discharged from the cutter chamber, and the kneaded material The liquefied component is liquefied and separated from the kneaded product by heating in a heating separation section.

  According to the present invention, the liquefied component contained in the additive is changed from a solid state to a liquid state by heating the kneaded product in the heating separation unit. Here, since the excavated soil contained in the kneaded material is solid even when heated, the liquefied component can be reliably separated from the kneaded material. As a result, the recovery rate of the additive can be increased.

  In the present invention, when the liquefaction component is composed of at least one of myristyl alcohol and cetyl alcohol, the melting point is in the range of 37 ° C to 51 ° C, so that the solid state can be maintained at the face temperature and the liquefaction can be maintained. It is possible to suppress the energy required for.

  In the present invention, when the liquefied component is composed of myristyl alcohol, the melting point is in the range of 37 ° C. to 40 ° C., so that the solid state can be maintained at the face temperature and the energy required for liquefaction is further increased. Can be suppressed.

  In the present invention, the heating separation unit includes a sieve unit on which the kneaded product is placed and a heat source that generates heat, and the kneaded product placed on the sieve unit is heated by heat from the heat source. In the case where the liquefied component is liquefied and allowed to flow out from the gap between the sieve portions, the water and the liquefied component contained in the kneaded product can be easily separated.

  In the present invention, the sieving portion is configured in a cylindrical bowl shape in which a plurality of rod-shaped members are arranged along a peripheral surface, and the kneaded product is supplied to the inside of the cocoon when the kneaded product is heated. Is rotated around the axis, the kneaded material inside the jar is stirred by the rotation of the sieve part, so that the whole kneaded material can be easily heated and solid-liquid separation is promoted, and the additive is recovered. The rate can be further increased.

  In the present invention, the heat source is constituted by a warm air generating section that generates warm air, and when the kneaded product is heated, the warm air is blown onto the kneaded product placed on the sieve unit to heat the kneaded product. In this case, the kneaded product can be heated with warm air, solid-liquid separation of the kneaded product can be promoted, and the additive recovery rate can be further increased.

  The present invention also provides an additive injection portion for injecting an additive into a cutter chamber formed between the face and the partition wall, and a kneaded product for discharging the additive and the excavated soil from the cutter chamber. In the mud pressure shield system provided with a discharge part, the additive injection part includes an additive containing a liquefied component that is solid at a face temperature and liquefied at a liquefaction temperature higher than the face temperature. And a heating separation unit for injecting into the cutter chamber, heating the kneaded product discharged from the kneaded product discharge unit, liquefying the liquefied component and separating it from the kneaded product. Features.

  ADVANTAGE OF THE INVENTION According to this invention, the recovery rate of an additive can be raised in the mud pressure shield construction method which inject | pours an additive into a cutter chamber and knead | mixes with excavated soil.

It is a figure explaining the whole structure of a mud pressure shield system. It is a figure explaining the shield machine and additive-separation supply apparatus of 1st Embodiment. It is a figure explaining a liquefied component, (a) is a figure which shows a mode during heating with warm air, (b) is a figure which shows a mode that the liquefied component after melting is cooled. (A) is sectional drawing explaining the heating separation part of 1st Embodiment. (B) is AA sectional drawing in (a). (C) is the elements on larger scale of a bowl-shaped sieve part. It is sectional drawing explaining the modification of a heating separation part. It is a figure explaining the shield machine and additive material separation supply apparatus of 2nd Embodiment. It is an enlarged view of an additive-separation supply apparatus.

  Embodiments of the present invention will be described below with reference to the drawings. The mud pressure shield system shown in FIG. 1 has a hermetic shield machine 1 and an additive material separating and supplying device 2.

  In this system, an additive (a mixture of bentonite mud water and a liquefied component, details will be described later) is supplied from the additive separation and supply device 2 to the cutter chamber 3, and the ground is excavated by the sealed shield machine 1. Then, the kneaded material of the excavated earth and additive is discharged from the cutter chamber 3 by the screw conveyor 4 and supplied to the additive separating and supplying apparatus 2. And in the additive-separation supply apparatus 2, an additive is isolate | separated and collect | recovered from a kneaded material.

  The collected additive material is supplied again to the cutter chamber 3 through the additive material supply pipe 24. The earth and sand (residue) after the additive is separated is transferred to the start shaft 6 by the shear steel wheel 5. In the start shaft 6, the shear steel wheel 5 loaded with earth and sand is lifted by a crane 7 and is put into a hopper 8 installed on the ground. The earth and sand in the hopper 8 is carried out to a disposal site by a truck.

  A sealed shield machine 1 illustrated in FIG. 2 includes a skin plate 11, a cutter head 12, a partition wall 13, a drive device 14, an erector 15, a shield jack 16, a tail seal 17, and a screw conveyor 4. Have.

  The skin plate 11 is a cylindrical member made of iron plate that constitutes the outer shell portion of the hermetic shield machine 1. The cutter head 12 is a disk-like member provided with a plurality of bits 12a for excavating the ground, and is attached to the front end portion of the skin plate 11 in the excavation direction in a rotatable state. The partition wall 13 is a plate-like member provided on the rear side in the digging direction with respect to the cutter head 12, and partitions the cutter chamber 3 with the cutter head 12.

  The cutter chamber 3 is a space filled with mud, and is a part that enables excavation while stabilizing the face by pressure-balancing the mud and the face in the cutter chamber 3. . As described above, the additive material from the additive material separation and supply device 2 is supplied to the cutter chamber 3 and is kneaded with excavated soil to improve the plastic fluidity and water stoppage in the mud.

  The drive device 14 is a drive source for rotating the cutter head 12, and is attached to the rear surface side of the partition wall 13. The erector 15 is a device that moves the segment 18 that is a component of the shield tunnel to a predetermined position. The shield jack 16 is a part that obtains a reaction force from an existing segment 18 located rearward in the excavation direction and obtains a propulsive force of the sealed shield machine 1. The tail seal 17 is a part for suppressing the intrusion of a backing material or groundwater.

  The screw conveyor 4 corresponds to a kneaded material discharge unit that discharges mud (kneaded material) in the cutter chamber 3. The inlet end of the screw conveyor 4 communicates with the cutter chamber 3. On the other hand, the outlet end of the screw conveyor 4 is connected to the inlet of the heating separation unit 21 included in the additive material separation and supply device 2. The screw conveyor 4 has a screw 4b disposed in a circular tube 4a having a diameter of 750 to 850 mm, for example. By rotating the screw 4b at a speed of about 5 to 8 rotations per minute, mud is removed. It sends out to the additive material separation supply apparatus 2 side.

  Next, the additive material separating and supplying apparatus 2 will be described. As shown in FIG. 2, the additive material separation and supply device 2 includes a heating separation unit 21, an additive material storage unit 22, an additive material supply pump 23, an additive material supply pipe 24, and an additive material supplementing unit 25. .

  The heating separation unit 21 is a part that liquefies the liquefied component contained in the additive by heating the mud supplied from the screw conveyor 4 and discharges it together with the water and earth and sand particles contained in the mud. As a result, the mud is separated into an earth and sand component mainly containing crushed stones and gravel and an additive mainly containing a liquefied component, water and earth and sand particles. The heating separation unit 21 will be described in detail later.

  The additive material storage part 22 is a part where the additive material is stored. The additive to be stored includes those prepared in advance and those separated by the heating separation unit 21. The additive storage part 22 of this embodiment is comprised by the substantially rectangular parallelepiped box, and is arrange | positioned under the heating separation part 21. As shown in FIG. Then, the additive material separated by the heating separation unit 21 flows down and stored in the additive material storage unit 22. As will be described later, the additive in the present embodiment includes a liquefied component that becomes solid at room temperature (20 ° C.). For this reason, the additive storage part 22 is provided with a stirring member for making the liquefied component into sand particles (not shown).

  The additive supply pump 23 is a part that functions as an additive injection part together with the additive supply pipe 24, and sends the additive stored in the additive storage part 22 toward the cutter chamber 3. The additive supply pump 23 of the present embodiment is configured by a plunger type pump or a screw type pump. In the plunger type pump, the additive is delivered by reciprocating a cylinder (not shown) in the cylinder, and in the screw type pump, the screw is rotated in the cylinder.

  The additive material supply pipe 24 is a pipe material that guides the additive material fed by the additive material supply pump 23 to the cutter chamber 3. The inlet end of the additive supply pipe 24 communicates with the delivery port of the additive supply pump 23, and the outlet end communicates with the cutter chamber 3 through the opening of the partition wall 13. The additive material replenishment unit 25 is a part that supplements a deficient additive component when the additive material in the additive material storage unit 22 is injected into the cutter chamber 3. In the present embodiment, bentonite mud and liquefied components are used as additives, so the additive replenishment unit 25 replenishes these additives by injecting bentonite and liquefied components into the additive supply pipe 24. .

  Next, the additive material will be described. The additive is a fluid kneaded in the cutter chamber 3 with the earth and sand excavated by the cutter head 12, and is added to improve the plastic fluidity and water stoppage of the mud in the cutter chamber 3. As described above, bentonite mud and liquefied components are included in the additive of the present embodiment. Bentonite is a kind of clay, has high water absorbability, and has good dispersibility in muddy water. Since this bentonite absorbs and holds water, the lubricity in the mud can be improved by kneading. Moreover, by injecting bentonite mud into the cutter chamber 3, the viscosity of the mud can be adjusted and the face can be stabilized.

  The liquefied component is also added to improve the plastic fluidity and water stopping property in the mud and corresponds to the fluidized component. As the liquefied component in the present embodiment, a substance that is solid at the face temperature (face temperature) and is liquefied at a liquefaction temperature higher than the face temperature is used. For example, a trade name “Calcoal” manufactured by Kao Corporation is preferably used.

This calcol is a substance mainly composed of higher alcohol (purity 98%). In this embodiment, “Calcoal 2098” mainly composed of C ₁₂ lauryl alcohol, “Calcoal 4098” mainly composed of C ₁₄ myristyl alcohol, “Calcol 6098” mainly composed of C ₁₆ cetyl alcohol, Further, “Calcor 8098” mainly composed of C ₁₈ stearyl alcohol can be used.

  All of these products are solid at room temperature. For example, the melting point of calcoal 2098 is 23.5 ° C. to 26.5 ° C., and the melting point of calcoal 4098 is 37 ° C. to 40 ° C. Further, the melting point of calcoal 6098 is 48 ° C. to 51 ° C., and the melting point of calcoal 8098 is 57 ° C. to 60 ° C. All of these products are wax-like white solids at room temperature, and are in the form of lumps or granules.

  FIG. 3 shows the state of the melting test for calcoal. In this melting test, crushed stone, bentonite mud and calcoal (Calcoal 4098) were mixed to prepare a simulated mud, and the simulated mud was spread on a stainless steel square bat. And as shown to Fig.3 (a), the warm air from a dryer was sprayed on the muddy mud. As a result, as indicated by the symbol X, it was confirmed that calcoal was melted. FIG. 3B shows a state in which a square bat in which the calcoal is melted is placed on ice. As a result of this cooling, as indicated by the symbol Y, solidification of the molten calcol was confirmed.

  From the above results, when calcoal is used as a liquefied component, it is liquefied by heating so that it can be separated from mud and solidified by cooling, and can be reused as an additive. Although the above melting test was performed on calcoal 4098, other types of calcoal can be used in the same manner because they have the same property of being melted by heating and solidifying below the melting point.

  Here, the tunnel temperature in the shield method is determined to be 37 ° C. or lower. From this viewpoint, the melting point of the liquefied component is preferably 37 ° C. or higher. On the other hand, if the melting point is too high, a large amount of energy is required for heating the liquefied component, the amount of fuel and electricity consumed increases, and the tunnel temperature rises excessively. From this viewpoint, the melting point of the liquefied component is preferably low. Considering these conditions, as the liquefied component, calcoal 4098 (melting point: 37 to 40 ° C.) and calcoal 6098 (melting point: 48 to 51 ° C.) are preferable, and calcoal 4098 is particularly preferable.

In addition, since each calcol has a different melting point, it is possible to cope with various working face temperatures by selecting a product having a melting point suitable for the working face temperature. For example, calcoal 2098 (melting point: 23.5 to 26.5 ° C.) and calcoal 4098 are used in a low temperature environment such as winter and cold regions, and calcoal 6098 and calcoal 8098 (melting point) in a high temperature environment of summer and high geothermal heat. 57-60 ° C.) may be used. In other words, a higher alcohol having a relatively low carbon number of about C _{10 to} C ₁₂ may be used in a low temperature environment, and a higher alcohol having a relatively high carbon number of about C _{16 to} C ₁₈ may be used in a high temperature environment. .

  Next, the heating separation unit 21 will be described in detail. The heating separation unit 21 includes a sieve unit on which the kneaded material is placed, a heat source that generates heat, and a main body case. For example, in the heating separation unit 21 shown in FIGS. 4A to 4C, a sieve portion is configured by the cylindrical scissors member 31, and a heat source is configured by the hot air generation unit 32.

  The cylindrical rod member 31 is a member configured in a cylindrical rod shape by arranging a plurality of rod-shaped members 31a along the circumferential surface, and is made of, for example, iron. The cylindrical scissors member 31 of the present embodiment is made, for example, in a size of 1 m to 1 m 20 cm in diameter and 2 m to 2 m 50 cm in length in the central axis direction. In addition, a magnitude | size is an example and is not limited to this magnitude | size.

  Flat circular ring-shaped end plates 31 b are attached to both ends in the longitudinal direction of the cylindrical flange member 31. Moreover, as shown in FIGS. 4B and 4C, each rod-shaped member 31a is constituted by a square pipe, and by arranging square corners facing each other, about 0.25 mm to 0.5 mm. An extremely narrow gap d is formed.

  As shown in FIGS. 4 (a) and 4 (b), the inner screw 33 for transferring the kneaded material sent from the screw conveyor 4 within the cylindrical rod member 31 to the inner space of the cylindrical rod member 31. Is provided. By providing the inner screw 33 separately from the screw conveyor 4, the feed speed of the kneaded material in the screw conveyor 4 and the feed speed of the kneaded material in the cylindrical rod member 31 can be adjusted as appropriate.

  In this heating / separating section 21, when the additive is separated from the kneaded product, each of the cylindrical rod member 31 and the rod screw 33 is rotated about its axis. In this case, the moving speed of the kneaded material in the basket is determined according to the difference in rotational speed between the cylindrical bowl member 31 and the bowl screw 33. When the rotational speeds of the cylindrical rod member 31 and the inner rod screw 33 are individually set, the stirring of the kneaded material accompanying the rotation of the cylindrical rod member 31 and the transfer speed of the kneaded material accompanying the rotation of the inner rod screw 33 are balanced. And the separation efficiency of the additive from the kneaded product can be increased.

  The earth and sand from which the additive has been separated is discharged from the rear end of the cylindrical rod member 31 by the rod screw 33. This earth and sand is discharged out of the heating separation section 21 through the discharge section 34, transferred to the start shaft 6 by the shear steel wheel 5, and then carried out to the ground.

  The warm air generator 32 is a part that generates warm air. The hot air generating unit 32 includes a heating wire and a fan (both not shown) inside the heat insulating case, and heats the outside air taken from the intake pipe 35 and sends it to the air supply pipe 36. The air supply pipe 36 guides the heated air to the ceiling portion of the main body case 37. The temperature of the warm air generated from the warm air generating unit 32 is set to a temperature higher than the melting point of the liquefied component. In other words, it is set to a temperature at which the amount of heat necessary for melting the liquefied component contained in the kneaded product can be given. The hot air generator 32 may have another configuration as long as it can generate hot air.

  As shown in FIG. 4B, the main body case 37 is a hollow body that accommodates the cylindrical rod member 31 and the rod screw 33 in a rotatable state. An outlet of the air supply pipe 36 is opened in the ceiling portion of the main body case 37. For this reason, the warm air from the warm air generator 32 flows downward in the internal space of the main body case 37. The bottom surface of the main body case 37 is inclined downward toward the opening of the discharge pipe 38. As a result, the liquid additive that has fallen to the bottom surface flows along the downward slope and is guided to the discharge pipe 38. Further, since the warm air flows downward, the liquid additive is guided to the discharge pipe 38 by the flow of the warm air. The lower end of the discharge pipe 38 communicates with the additive material storage unit 22. Accordingly, the additive material flowing into the discharge pipe 38 is stored in the additive material storage unit 22.

  Next, the mud pressure shield construction method of this embodiment will be described.

  As shown in FIG. 2, in this mud pressure shield method, the additive (bentonite mud water, liquefied component) stored in the additive storage part 22 is sent out toward the cutter chamber 3 by the additive supply pump 23. This additive is supplied to the cutter chamber 3 through the additive supply pipe 24. At this time, bentonite and the liquefied component are replenished from the additive replenishment section 25 toward the additive supply pipe 24, and the plastic fluidity and water stoppage of the kneaded product are adjusted.

  Here, the amount of bentonite or liquefied component to be replenished is determined according to the results of plastic flowability and water-stopping tests performed in advance. For example, the plastic fluidity is determined based on the result of the slump test (JIS A 1101). Further, the water stoppage is determined based on the result of the soil permeability test (JIS A 1218).

  In the cutter chamber 3, the injected additive material and excavated earth and sand are kneaded and adjusted to mud having desired plastic fluidity and water-stopping property. By filling the inside of the cutter chamber 3 with the adjusted mud, excavation is performed while preventing the face from collapsing. Then, the mud in the cutter chamber 3 is sent to the heating separation unit 21 by the screw conveyor 4.

  In the heating separation unit 21, as described above, the cylindrical dredging member 31 and the dredging screw 33 rotate around the axis, so that the supplied mud is being stirred by the cylindrical dredging member 31 and the dredging screw 33, It is conveyed to the discharge unit 34 side. At this time, mud moisture (moisture and fine particles) contained in the mud flows out of the rod through the gap d between the rod-shaped members 31a of the cylindrical rod member 31, flows down the bottom of the main body case 37, and the discharge pipe 38. Flow into. And it is stored by the additive storage part 22 as an additive. The liquefied component contained in the mud is fluidized by being heated by the hot air from the hot air generating unit 32. The liquefied component in the fluidized state flows out of the cylindrical rod member 31 and is stored in the additive material storage unit 22 in the same manner as the mud moisture.

  Therefore, the kneaded material from the cutter chamber is separated in the heating separation unit 21 into an additive containing bentonite mud water or a liquefied component, and earth and sand (residue) after the additive is separated. Then, the separated additive is collected in the additive storage part 22 and sent out again to the cutter chamber.

  As described above, in the mud pressure shield system of the present embodiment, a liquefied component (higher alcohol such as calcoal) liquefied at a liquefaction temperature higher than the face temperature is included in the additive, and the cutter chamber 3 The kneaded product is heated by the heating separation unit 21 to change the liquefied component from solid to liquid and separate from the earth and sand. Here, since the excavated soil contained in the kneaded material is solid even when heated, the liquefied component can be reliably separated from the excavated soil. As a result, the recovery rate of the additive can be increased.

  In addition, when Calcoal 4098 (Myristyl Alcohol) or Calcoal 6098 (Cetyl Alcohol) having a melting point in the range of 37 to 51 ° C. is used as the liquefaction component, the solid can be maintained at the face temperature, and the liquefaction Necessary heating energy can be suppressed. In addition, Calcoal 4098 and 6098 may be used alone or in a blend. And when Calcoal 4098 whose melting point is 37-40 degreeC is used, since melting | fusing point is near the upper limit of the working temperature in a shield tunnel, the excessive temperature rise in a tunnel can be suppressed easily.

  In addition, regarding the heating separation unit 21, in the present embodiment, the heating separation unit 21 includes a sieving part (cylindrical ridge member 31) on which the kneaded material is placed, and a heat source (warm air generating part 32) that generates heat, and is placed on the sieving part. By heating the resulting kneaded material with heat from a heat source, the liquefied component is liquefied and flows out from the gaps in the sieve portion, so that the liquefied component can be easily separated from the earth and sand.

  Furthermore, regarding the sieve portion, in the present embodiment, when a plurality of rod-like members 31a are formed in a cylindrical bowl shape arranged along the circumferential surface and rotated around the axis, mud is removed by rotation of the sieve portion. Since it can stir, it becomes easy to apply heat equally, and the water and the liquefied component contained in the kneaded product can be easily separated from the earth and sand.

  In addition, regarding the heat source, in the present embodiment, it is constituted by the warm air generating unit 32 that generates warm air, and when the kneaded product is heated, it is heated by blowing the warm air on the kneaded product placed on the sieve unit. The kneaded product can be heated by warm air, and solid-liquid separation of the kneaded product can be promoted. Thereby, the collection | recovery rate of an additive can be raised further.

  By the way, the description regarding the above embodiment is for making an understanding of this invention easy, and does not limit this invention. The present invention can be changed and improved without departing from the spirit and purpose of the present invention, and the present invention naturally includes equivalents thereof. For example, you may comprise as follows.

  FIG. 5 is a cross-sectional view illustrating a modified example of the heating separation unit 21A, and corresponds to FIG. 4B described above. The differences from the heating separation unit 21 in the first embodiment are as follows.

  The first difference is that an electric heater 41 is used as a heat source, and this electric heater 41 is embedded in the main body case 37 '. That is, the temperature of the internal space of the main body case 37 ′ is increased by the electric heater 41, and the kneaded material fed by the cylindrical rod member 31 and the rod screw 33 is heated.

  The second difference is that the inner surface of the main body case 37 ′ is covered with a stainless steel plate 42. By covering with the stainless steel plate 42, it is possible to guide the additive to the discharge pipe 38 while ensuring heat transfer to the kneaded material.

  Other configurations in this modified example are the same as those in the above-described embodiment, and thus description thereof is omitted. And also in this modification, the recovery rate of the additive can be increased as in the above-described embodiment.

  6 and 7 are diagrams for explaining the second embodiment. In this 2nd Embodiment, the point which has installed the additive-separated supply apparatus 2 'in the start shaft 6 differs greatly from 1st Embodiment. Further, since the additive material separation and supply device 2 ′ is installed in the start shaft 6, the kneaded material discharged from the screw conveyor 4 is carried to the additive material separation and supply device 2 ′ by the belt conveyor 51.

  Moreover, in 2nd Embodiment, the format of a heating separation part is also different from 1st Embodiment. As shown in FIG. 7, the heating separation unit 21 </ b> B of the second embodiment is configured by a vibrating sieve with a heating mechanism. That is, the heating separation unit 21 </ b> B includes a vibration sieve 52, a housing 53 that houses the vibration sieve 52, and a heater 54 with a fan attached to the ceiling surface of the housing 53.

  The vibration sieve 52 can be constituted by, for example, a large number of bar-shaped members 52a arranged side by side and a vibration mechanism 52b that vibrates these bar-shaped members 52a in the vertical direction. In this configuration, the additive can be separated from the kneaded material placed on the rod-shaped member 52a by moving the rod-shaped member 52a in the vertical direction.

  Further, the vibration sieve 52 is arranged on the back side of the net member so as to cross the net member having flexibility, and a plurality of cross beams that support the net member from below, and the cross beam is a net member. You may comprise by the moving mechanism made to reciprocate to the longitudinal direction of a material (all are not shown in figure). In this configuration, the additive can be separated from the kneaded material by reciprocally moving the cross beams in the longitudinal direction of the net material while feeding the kneaded material placed on the net material to the downstream side.

  In addition, in this 2nd Embodiment, you may install the additive-separation supply apparatus 2 'on the ground. In this case, the kneaded material transported to the start shaft 6 is lifted to the ground together with the scrap steel wheel 5 by the crane 7 and processed by the ground additive material separating and supplying apparatus 2 '. Even if comprised in this way, there exists an effect similar to the above-mentioned structure.

  Further, in each of the above-described embodiments, the system in which the additive separated by the heating separation unit 21 is supplied to the cutter chamber 3 of the sealed shield machine 1 and reused is exemplified. The separated additive may be used in other shield machines or may be used for other purposes.

DESCRIPTION OF SYMBOLS 1 Sealed shield machine 2 Additive material separation supply equipment 3 Cutter chamber 4 Screw conveyor (4a circular pipe, 4b screw)
5 Steel shaft 6 Starting shaft 7 Crane 8 Hopper 11 Skin plate 12 Cutter head 13 Bulkhead 14 Drive device 15 Elector 16 Shield jack 17 Tail seal 18 Segments 21, 21A, 21B Heating separation part 22 Additive storage part 23 Additive supply pump 23 24 Additive material supply pipe 25 Additive material replenishment part 31 Cylindrical scissor member 32 Hot air generating part 33 Saddle screw 34 Discharge part 35 Intake pipe 36 Inlet pipe 37, 37 'Main body case 38 Discharge pipe 41 Electric heater 42 Stainless steel plate 51 Belt conveyor 52 Vibrating sieve 53 Housing 54 Heater with fan

Claims (7)

In the mud pressure shield method of injecting additive material into the cutter chamber formed between the face and the bulkhead and kneading with the excavated soil,
As the additive, a material containing a liquefied component that is solid at the face temperature and liquefied at a liquefaction temperature higher than the face temperature,
Discharging the additive and the excavated soil kneaded material from the cutter chamber;
A mud pressure shield method characterized in that the liquefied component is liquefied and separated from the kneaded product by heating the kneaded product in a heating separation section.   The mud pressure shield method according to claim 1, wherein the liquefaction component is at least one of myristyl alcohol and cetyl alcohol.   The mud pressure shield method according to claim 2, wherein the liquefaction component is myristyl alcohol.   The heating separation unit has a sieve part on which the kneaded product is placed and a heat source that generates heat, and heats the kneaded product placed on the sieve part with heat from the heat source, so that the liquefied component The mud pressure shield method according to any one of claims 1 to 3, wherein the liquefaction is caused to flow out from the gap between the sieve portions. The sieve portion is configured in a cylindrical bowl shape in which a plurality of rod-shaped members are arranged along the peripheral surface,
5. The mud pressure shield method according to claim 4, wherein, when the kneaded material is heated, the sieve portion is rotated about an axis while the kneaded material is supplied into the ridge. The heat source is constituted by a hot air generator that generates hot air,
6. The mud pressure shield method according to claim 4, wherein when the kneaded product is heated, the warm air is blown onto the kneaded product placed on the sieve portion to heat the kneaded product. An additive injection portion for injecting an additive into a cutter chamber formed between the face and the partition wall, and a kneaded material discharge portion for discharging the additive and the kneaded material of the excavated soil from the cutter chamber. In the mud pressure shield system,
The additive injecting section is for injecting into the cutter chamber an additive containing a liquefied component that is solid at the face temperature and liquefied at a liquefaction temperature higher than the face temperature,
A mud pressure shield system comprising: a heating separation unit that heats the kneaded material discharged from the kneaded material discharge unit to liquefy the liquefied component and separate it from the kneaded material.