Simulated test device for earth pressure balance shield tunneling machine
The simulated test device for earth pressure balance shield tunneling machines addresses the lack of control mechanisms by simulating mud pressure, intake, and discharge conditions, enhancing excavation efficiency and safety.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-09-20
- Publication Date
- 2026-04-02
AI Technical Summary
Existing earth pressure balance shield tunneling machines lack mechanisms for variable control of plug zone length and simulation of pressure applied to mud, intake, and discharge conditions, making efficient excavation challenging, especially in high-pressure water-storage environments.
A simulated test device for earth pressure balance shield tunneling machines that includes an earth pressure chamber, screw conveyor, partition plate, and rotary stirring jig, equipped with pressure gauges and adjustable components to simulate and reproduce mud management conditions, allowing prediction of excavation effects.
Enables simulation and prediction of mud pressure conditions, intake, and discharge scenarios, facilitating safer and more efficient tunneling operations by forming a stable watertight plug.
Smart Images
Figure 2026057255000001_ABST
Abstract
Description
Technical Field
[0004] , , , ,
[0003]
[0001] The present invention relates to a simulation test device for an earth pressure shield tunneling machine, and particularly to a simulation test device for an earth pressure shield tunneling machine for evaluating the properties of earth formed by excavated soil and sand, which is taken into a screw conveyor and discharged after being stirred with an additive in an earth pressure chamber.
Background Art
[0002] An earth pressure type shield tunneling machine (earth pressure shield tunneling machine) is a shield tunneling machine having a known structure that takes in and fills the soil and sand excavated by a cutter head (rotary cutter) at the tip into a rear earth pressure chamber, stabilizes the face by the earth pressure of the filled excavated soil and sand, and advances the tunnel while discharging the excavated soil and sand from the earth pressure chamber through a screw conveyor. In an earth pressure shield tunneling machine, the excavated soil and sand taken into and filled in the earth pressure chamber are preferably in a state of being fluidized as earth after being added and mixed with an additive such as a mud material, and in this state, the face of the tunnel is continuously discharged from the earth pressure chamber through a screw conveyor while being pressed against the earth pressure and water pressure in a balanced manner.
[0003] Further, in an earth pressure shield tunneling machine, a water stop plug made of earth is preferably formed inside the screw conveyor so as not to cause an explosion by counteracting the water pressure and earth pressure of the face. By being able to form such a water stop plug made of earth in a stable state, it becomes possible to safely and efficiently advance even when excavating a waterlogged sand and gravel layer where a high water pressure acts. For this reason, during actual tunneling construction using an earth pressure shield tunneling machine, the flow state of the earth in the earth pressure chamber, the type and addition amount of the additive mixed in the earth, the stirring speed of the earth accompanying the rotation of the rotary cutter, the pressurization situation of the earth due to the extension of the shield jack, the intake situation of the excavated soil and sand, the discharge situation of the earth through the screw conveyor, etc. are managed.
[0004] On the other hand, prior to actual excavation work using a mud pressure balance shield tunneling machine, if it were possible to know in advance, for example, the appropriate discharge conditions of mud by a screw conveyor, depending on the geology of the ground to be excavated, in particular, so that the watertight plug is formed in a stable state, it is thought that it would be possible to excavate more safely and efficiently with the mud pressure balance shield tunneling machine. For this reason, experimental apparatus has been proposed (see, for example, Non-Patent Document 1). [Prior art documents] [Non-patent literature]
[0005] [Non-Patent Document 1] Proceedings of the 49th Annual Scientific Conference of the Japan Society of Civil Engineers (September 1994), pp. 1296 and 1297, "Development of a Screw Soil Removal Mechanism under High Water Pressure in Earth Pressure Balance Shield Tunneling Method" [Overview of the project] [Problems that the invention aims to solve]
[0006] The variable-length plug zone experimental apparatus described in Figure 1 of Non-Patent Literature 1 is broadly divided into a model soil tank section and a soil removal mechanism section. The soil removal mechanism consists of a screw conveyor, a plug zone variable jack, a screw drive, etc. The experimental apparatus in Non-Patent Literature 1 is designed to confirm in advance that stable soil removal is possible by making the plug zone length, which is the length of the watertight plug formed by the mud inside the screw conveyor, variable in accordance with the soil type and excavation conditions, particularly when applying the earth pressure balance shield tunneling method to ground with high-pressure water-storage sand or gravel layers, so as not to cause the eruption phenomenon of excavated soil.
[0007] However, in the variable-length plug zone experimental apparatus described in Non-Patent Literature 1, it is confirmed in advance that stable soil removal is possible by making the plug zone length, which is the length of the water-stopping plug formed inside the screw conveyor, variable by a plug zone variable jack. However, in actual construction sites, mud pressure balance shield tunneling machines are rarely equipped with a mechanism that allows for variable control of the plug zone length by having a plug zone variable jack. Generally, the current practice is to manage the pressure applied to the mud by the extension of the shield jack, the intake of excavated soil into the earth pressure chamber, the flow state of the mud, and the discharge state of the mud via the screw conveyor so that a water-stopping plug that can withstand the water pressure and earth pressure at the tunnel face is formed in a stable state inside the screw conveyor. For these reasons, there is a need to develop an experimental apparatus that can simulate and reproduce management items other than the plug zone length of the water-stopping plug, which are actually managed at construction sites, particularly the pressure applied to the mud due to the extension of the shield jack, the intake of excavated soil, the flow state of the mud, and the discharge of mud via the screw conveyor, thereby enabling a certain degree of prediction of the effects of these management items. Furthermore, it is believed that predicting the effects of these management items in advance will enable more efficient and appropriate management of excavation work according to the geological conditions of the ground being excavated.
[0008] The present invention aims to provide a simulated test device for an earth pressure balance shield tunneling machine that, prior to actual excavation work using the earth pressure balance shield tunneling machine, can simulate and reproduce management items such as the pressure applied to the mud due to the extension of the shield jacks, the intake of excavated soil, the flow state of the mud, and the discharge of mud via a screw conveyor, thereby enabling prediction of the effects of these management items. [Means for solving the problem]
[0009] The present invention relates to a simulated test apparatus for an earth pressure balance shield tunneling machine for evaluating the properties of mud produced by excavated soil that is mixed with additives in the earth pressure chamber and then taken into a screw conveyor for discharge, comprising: an earth pressure chamber cylindrical body in which a simulated earth pressure chamber is formed and filled with mud to be evaluated; a simulated partition plate joined to the earth pressure chamber cylindrical body with one end opening closed; a simulated screw conveyor in which one end of an outer cylindrical body is joined to the soil discharge opening of the simulated partition plate and screw blades are rotatably housed inside the outer cylindrical body; a partition plate arranged to slide along the inner circumferential surface of the earth pressure chamber cylindrical body and to move back and forth in the axial direction of the earth pressure chamber cylindrical body; and a rotating stirring jig rotatably arranged in the simulated earth pressure chamber, with a stirring rod protruding radially outward, in the inner region of the earth pressure chamber cylindrical body between the partition plate and the simulated partition plate, which serves as the simulated earth pressure chamber. The above objective is achieved by providing a simulated earth pressure shield excavator, comprising the following components: the partition plate is slidably passed through the center of an end-closing plate joined to close the other end opening of the earth pressure chamber cylinder, and joined to one end of a cylindrical reciprocating rod extending axially from the earth pressure chamber cylinder, so that it moves back and forth axially from the earth pressure chamber cylinder by the drive of an expandable jack connected to a support base to which the other end of the cylindrical reciprocating rod is joined; and the rotary stirring jig is inserted through the cylindrical reciprocating rod and joined to one end of a rotary support rod protruding into the simulated earth pressure chamber, so that it rotates inside the simulated earth pressure chamber filled with mud by the rotation operation of a rotary operation unit attached to the other end of the rotary support rod which extends axially beyond the support base.
[0010] Furthermore, in the simulated test device for the earth pressure balance shield tunneling machine of the present invention, it is preferable that a plurality of pressure gauges are attached to the outer cylindrical body of the simulated screw conveyor at predetermined intervals in the longitudinal direction, facing the inside of the outer cylindrical body.
[0011] Furthermore, in the simulated test device for the earth pressure balance shield tunneling machine of the present invention, it is preferable that the telescopic jacks that move the partition plate back and forth in the axial direction of the earth pressure chamber cylinder are connected to the ends on both sides of the support base to which the other end of the cylindrical retractable rod is joined, and a pair of these jacks are arranged on both sides of the earth pressure chamber cylinder.
[0012] Furthermore, it is preferable that the simulated test device for the earth pressure balance shield tunneling machine of the present invention has a fixed stirring rod attached to it, which is fixed to a portion of the earth pressure chamber cylindrical body adjacent to the simulated partition wall plate and protrudes radially inward into the simulated earth pressure chamber.
[0013] Furthermore, it is preferable that the simulated test device for a mud pressure shield excavator of the present invention is configured such that one or more spacer pipes having a predetermined axial length are detachably attached to the rotating support rod, interposed between the support base and the rotating operation unit, allowing adjustment of the protrusion length of the rotating stirring jig from the partition plate in the simulated earth pressure chamber.
[0014] Furthermore, it is preferable that the simulated test device for the earth pressure balance shield tunneling machine of the present invention is equipped with a rotation prevention rod, one end of which is connected to the partition plate, and which slidably penetrates the end closing plate and has the other end protruding to the outside of the end closing plate, and is mounted in a state where it extends parallel to the cylindrical reciprocating rod.
[0015] Furthermore, it is preferable that the simulated earth pressure shield tunneling machine simulation device of the present invention has an additive supply pipe, capable of supplying additives to the simulated earth pressure chamber, connected to and attached to the cylindrical body of the earth pressure chamber.
[0016] Furthermore, in the simulated earth pressure shield tunneling machine simulation device of the present invention, it is preferable that a water tank for storing water supplied to the simulated earth pressure chamber is installed adjacent to the cylindrical body of the earth pressure chamber. [Effects of the Invention]
[0017] According to the simulation test device for the earth pressure shield tunneling machine of the present invention, prior to the actual tunneling construction by the earth pressure shield tunneling machine, management items such as the pressurization situation of the earth due to the extension of the shield jack, the intake situation of the excavated soil and sand, the flow state of the earth, and the discharge situation of the earth through the screw conveyor can be simulated and reproduced, and the influence by these management items can be predicted.
Brief Description of the Drawings
[0018] [Figure 1] It is a side view for explaining the simulation test device for the earth pressure shield tunneling machine according to a preferred embodiment of the present invention. [Figure 2] It is a longitudinal sectional view along A-A of FIG. 1 for explaining the simulation test device for the earth pressure shield tunneling machine according to a preferred embodiment of the present invention. [Figure 3] It is a sectional view along B-B of FIG. 1 for explaining the part of the simulated earth pressure chamber by the earth pressure chamber cylinder. [Figure 4] It is a front view of the stirring blade rotation handle. [Figure 5] (a) to (e) are explanatory diagrams of an experimental method using the simulation test device for the earth pressure shield tunneling machine. [Figure 6] (a) to (e) are explanatory diagrams of an experimental method using the simulation test device for the earth pressure shield tunneling machine. [Figure 7] (a) to (d) are explanatory diagrams of an experimental method using the simulation test device for the earth pressure shield tunneling machine.
Modes for Carrying Out the Invention
[0019] The simulated earth pressure balance shield tunneling machine simulation device 10, shown in Figures 1 and 2, according to a preferred embodiment of the present invention, can be compactly installed in a laboratory, for example, and simulates the excavation conditions of an earth pressure balance shield tunneling machine. This device allows for a certain degree of prior understanding of management items, such as the pressure applied to the mud due to the extension of the shield jacks, the intake of excavated soil, the flow state of the mud, and the discharge of mud via a screw conveyor, depending on the geological conditions of the ground to be excavated, prior to actual excavation work using an earth pressure balance shield tunneling machine. Furthermore, the simulated test apparatus 10 of this embodiment is designed to allow prediction of the effects of the following control items: the pressure applied to the mud by the extension of the shield jack, the intake of excavated soil, the flow state of the mud, and the discharge state of the mud via the screw conveyor. In particular, it allows for the stable formation of a watertight plug made of mud inside the screw conveyor to prevent eruption in response to the water pressure and earth pressure at the excavation face.
[0020] And the simulation test device 10 of the present embodiment is a test device for evaluating the properties of soil formed by excavated soil and sand, which is taken into a screw conveyor and discharged after being stirred with an additive in an earth pressure chamber in an earth pressure balance shield tunneling machine (not shown). As shown in FIGS. 1 and 2, it includes a soil pressure chamber cylinder 12 in which a simulated soil pressure chamber 11 filled with the soil to be evaluated is formed, a simulated partition plate 13 joined by closing one end opening of the soil pressure chamber cylinder 12, a simulated screw conveyor 16 in which one end of an outer cylinder 14 is joined to the soil discharge opening 13a of the simulated partition plate 13 and a screw blade 15 is rotatably accommodated inside the outer cylinder 14, a partition plate 20 arranged to be able to advance and retreat in the axial direction X of the soil pressure chamber cylinder 12 while sliding along the inner peripheral surface of the soil pressure chamber cylinder 12, and a rotary stirring jig 26 rotatably arranged in the simulated soil pressure chamber 11 and having a stirring rod 26a protruding radially outward in the inner region of the soil pressure chamber cylinder 12 between the partition plate 20 and the simulated partition plate 13. The partition plate 20 is slidably penetrated through the central portion of an end closing plate 17 joined by closing the other end opening of the soil pressure chamber cylinder 12 and is joined to one end 21a of a cylindrical advancing and retreating rod 21 extending in the axial direction X of the soil pressure chamber cylinder 12. Thus, by driving a telescopic jack 23 connected to a support base portion 22 to which the other end 21b of the cylindrical advancing and retreating rod 21 is joined, it can advance and retreat in the axial direction X of the soil pressure chamber cylinder 12. The rotary stirring jig 26 is joined to one end 27a of a rotary support rod 27 inserted through the cylindrical advancing and retreating rod 21 and protruding into the simulated soil pressure chamber 11. Thus, by a rotary operation by a rotary operation portion 28 attached to the other end 27b of the rotary support rod 27 extending in the axial direction X beyond the support base portion 22, it can rotate inside the simulated soil pressure chamber 11 filled with soil.
[0021] Also, in the present embodiment, preferably, a plurality of pressure gauges 18, preferably known pressure sensors, are attached to the outer cylinder 14 of the simulated screw conveyor 16 so as to face the inside of the outer cylinder 14 at predetermined intervals in the length direction.
[0022] Furthermore, in this embodiment, the telescopic jacks 23 that move the partition plate 20 in the axial direction X of the earth pressure chamber cylindrical body 12 are preferably connected to the ends on both sides of the support base portion 22 to which the other end 21b of the cylindrical retractable rod 21 is joined, and are provided in pairs on both sides of the earth pressure chamber cylindrical body 12.
[0023] In this embodiment, as shown in Figure 1, the simulated test device 10 is integrally mounted on a support frame section 50 that is movable via casters 51, and is provided to be movable together with the support frame section 50. The support frame section 50 is formed by assembling various steel materials such as H-beams and angle steels, and preferably has a vertically elongated rectangular planar shape. Multiple stopper legs 52 are arranged on the support frame section 50, protruding downwards, and by moving the adjustment bolts 52a attached to the lower surface of these stopper legs 52 forward and backward, the support frame section 50 on which the simulated test device 10 is mounted can be temporarily fixed in a predetermined position after being moved. As described above, the simulated test device 10 is composed of a cylindrical earth pressure chamber 12, a simulated screw conveyor 16, a cylindrical forward and backward rod 21 (see Figure 2), a support base section 22 and an extendable jack 23, and a rotation operation section 28.
[0024] The earth pressure chamber cylinder 12, which constitutes the simulated test device 10, is made of a steel plate with a thickness of approximately 10 mm, as shown in Figure 2, and has a cylindrical shape with an outer diameter of approximately 300 mm and a length of approximately 930 mm. Joining flanges 12a are welded integrally to both ends of the earth pressure chamber cylinder 12, protruding outwards in an annular shape. A simulated partition plate 13 that closes the opening at one end and an end closing plate 17 that closes the opening at the other end are attached integrally to the earth pressure chamber cylinder 12 via these joining flanges 12a, for example, by bolt connections. Inside the earth pressure chamber cylinder 12, a partition plate 20, which will be described later, is arranged to slide along the inner circumferential surface and move back and forth in the axial direction X, forming a simulated earth pressure chamber 11 between it and the simulated partition plate 13. A rotating stirring jig 26 with a stirring rod 26a protruding from it is placed in the formed simulated earth pressure chamber 11. Furthermore, the earth pressure chamber cylindrical body 12 is preferably fixed to a portion adjacent to the simulated partition wall plate 13, and one or more fixed stirring rods 29 with an outer diameter of about 12 mm are attached to it, projecting radially inward into the simulated earth pressure chamber 11. In addition, the earth pressure chamber cylindrical body 12 is fixed to a portion adjacent to the simulated partition wall plate 13 and has an upper cylindrical body 12b with an opening / closing lid that serves as a soil input port, projecting upward, while a lower cylindrical body 12c with an opening / closing lid that serves as a soil discharge port is projecting downward (see Figure 1). The earth pressure chamber cylindrical body 12 may also be provided with a viewing window 12d at an appropriate position, for example, fitted with transparent tempered glass, which allows for visual inspection of the condition of the mud inside (see Figure 1).
[0025] The simulated screw conveyor 16, which constitutes the simulated test device 10, consists of an outer cylindrical body 14 made of steel pipe having an outer diameter of approximately 90 mm, for example, with a length of approximately 920 mm, and a screw blade 15 rotatably housed inside the outer cylindrical body 14. By integrally joining one end of the outer cylindrical body 14 to the soil discharge opening 13a of the simulated bulkhead plate 13, the simulated screw conveyor is provided coaxially and linearly with the soil pressure chamber cylindrical body 12, extending in the axial direction X of the soil pressure chamber cylindrical body 12. A drive mechanism 14b for rotating the screw blade 15 is attached to the rear end portion of the outer cylindrical body 14 of the simulated screw conveyor 16 via a connecting part 14a, and a soil discharge opening 14d that can be opened and closed via a gate valve 14c is provided. Furthermore, on the outer cylindrical body 14 of the simulated screw conveyor 16, multiple pressure gauges 18, preferably pressure sensors, are attached at predetermined intervals along the axial direction X, which is the length direction of the outer cylindrical body 14, for measuring the pressure exerted by the mud being transported backward via the simulated screw conveyor 16. The pressure sensors 18 can also be mounted on the earth pressure chamber cylinder 12, facing the simulated earth pressure chamber 11 (see Figure 3).
[0026] The cylindrical reciprocating rod 21 constituting the simulated test device 10 is made of, for example, a steel pipe with an outer diameter of about 70 mm and a length of, for example, about 1300 mm. The cylindrical reciprocating rod 21 is provided in a state in which it slidably penetrates the central part of the end closing plate 17, which is joined to close the opening at the other end of the earth pressure chamber cylinder 12, and a partition plate 20 made of a circular plate member is integrally joined to one end 21a which is positioned inside the earth pressure chamber cylinder 12. The partition plate 20 has an outer diameter similar to the inner diameter of the earth pressure chamber cylinder 12, and a known sealing member is attached to its peripheral edge, so that it can move back and forth in the axial direction X of the earth pressure chamber cylinder 12 while sliding along the inner circumferential surface of the earth pressure chamber cylinder 12 while maintaining a state of close contact with the inner circumferential surface of the earth pressure chamber cylinder 12. In this way, the partition plate 20 can form a simulated earth pressure chamber 11 between itself and the simulated partition plate 13.
[0027] Furthermore, the other end 21b of the cylindrical reciprocating rod 21, which is positioned on the outside of the earth pressure chamber cylinder 12, is joined to the support base 22. This allows the cylindrical reciprocating rod 21 to slide along with the partition plate 20 in the axial direction X of the earth pressure chamber cylinder 12 by the expansion and contraction of the telescopic jack 23 connected to the support base 22. The partition plate 20 can be a known screen structure that blocks the passage of soil particles while allowing the passage of water. This allows the partition plate 20 to move back and forth in the axial direction X while sliding along the inner circumferential surface of the earth pressure chamber cylinder 12, while the inside of the earth pressure chamber cylinder 12 is filled with pressurized water at a predetermined water pressure, making it possible to more faithfully reproduce the situation in which a shield tunneling machine excavates under a predetermined water pressure.
[0028] The telescopic jack 23, which moves the cylindrical retractable rod 21 together with the partition plate 20 in the axial direction X of the earth pressure chamber cylindrical body 12, is a known electric jack consisting of, for example, an electric cylinder 23a and a piston rod 23b (see Figures 5(a) to (e)) that extends and retracts from the electric cylinder 23a toward the opposite side of the simulated screw conveyor 16. The electric cylinder 23a and piston rod 23b of the telescopic jack 23 are arranged so that their axial directions are parallel to the axial direction X of the earth pressure chamber cylindrical body 12, and are each supported by a pair of support parts 30 that are integrally attached to the support frame part 50, and are mounted in pairs on both sides of the earth pressure chamber cylindrical body 12. The tip 23c of the piston rod 23b of these pair of telescopic jacks 23 is pin-connected to the connecting ribs 22a at both ends of the support base part 22, to which the other end 21b of the cylindrical retractable rod 21 is joined in the central part. This allows the support base 22, together with the cylindrical reciprocating rod 21 and the partition plate 20 which mimics the cutter plate of a shield tunneling machine, to move back and forth stably as a single unit in the axial direction X of the earth pressure chamber cylindrical body 12.
[0029] The support base portion 22 is formed to have a horizontally elongated box shape with an open front surface, formed by joining the ends of both sides of a pair of upper and lower strip-shaped plates 22b, for example, made of steel plate members, via end-joining vertical ribs 22c, and closing the back side with a strip-shaped back plate 22d. The other end 21b of the cylindrical retractable rod 21 is joined to the central part of the length direction of the back plate 22d from the back side, and a through hole 22e is formed in the inner region of the joined other end 21b of the cylindrical retractable rod 21, through which the rotating support rod 27 is slidably inserted. The spacer pipes 35a, 35b, 35c, and 35d, described later, are detachably fixed to the central part of the open front surface, straddling the pair of upper and lower strip-shaped plates 22b, with the rotating support rod 27 attached to its outer circumference. The connecting ribs 22a described above are attached to the end-joining vertical ribs 22c on both sides of the support base portion 22, so as to protrude outwards, and are joined together as a single unit.
[0030] The rotary operation unit 28, which constitutes the simulated test device 10, is provided by being integrally joined to the other end 27b of a rotary support rod 27, which is inserted through a cylindrical reciprocating rod 21 and positions a rotary stirring jig 26, joined to one end 27a, in the simulated earth pressure chamber 11. As shown in Figure 4, the rotary operation unit 28 is composed of, for example, six protruding rods 28b that extend radially at equal angular intervals from a joining base 28a (see Figure 1) that is joined to the other end 27b of the rotary support rod 27, and intermediate connecting rods 28c, preferably arranged in a regular hexagonal ring, that connect these protruding rods 28b to each other in the middle. The rotary operation unit 28 positions the six protruding rods 28b and the intermediate connecting rods 28c on a plane perpendicular to the cylindrical reciprocating rod 21 via the joining base 28a. This allows, for example, a worker holding the extension rod 28b to rotate the rotation operation unit 28, thereby smoothly rotating the rotary stirring jig 26, which is positioned in the simulated earth pressure chamber 11 via the rotary support rod 27, at a speed preferably similar to the rotation speed of the rotary cutter of the shield tunneling machine actually used during construction.
[0031] The rotating support rod 27, which rotates when the rotating operation unit 28 is operated, is made of a steel rod having a circular cross-section, for example, a diameter of about 30 mm, and a length considerably longer than the length of the cylindrical reciprocating rod 21, for example, about 2300 to 2500 mm. As shown in Figure 2, the rotating support rod 27 is slidably inserted into the hollow interior of the cylindrical reciprocating rod 21, and a rotating stirring jig 26 joined to one end 27a is placed in the simulated earth pressure chamber 11. The rotating support rod 27 extends axially beyond the cylindrical reciprocating rod 21 and the support base to the opposite side from the simulated screw conveyor 16, with the other end 27b being joined to the joining base 28a of the rotating operation unit 28.
[0032] The rotary stirring jig 26, which is joined to and supported by one end 27a of the rotary support rod 27, is composed of, for example, a cylindrical mounting sleeve 26b having an inner diameter similar to the outer diameter of the rotary support rod 27, and a plurality of stirring rods 26a, for example, with an outer diameter of about 12 mm, which are attached to the outer surface of the mounting sleeve 26b so as to protrude radially. As shown in Figures 2 and 3, in this embodiment, for example, a total of six stirring rods 26a are attached to the mounting sleeve 26b in groups of three, with their positions offset in the axial direction X. The three stirring rods 26a in each group are preferably provided so as to protrude radially at equal angular intervals of 120° in the circumferential direction, and the positions in the circumferential direction between each group are offset by 60°, so that when the rotary stirring jig 26 is viewed from the axial direction X, a total of six stirring rods 26a are arranged so as to protrude radially from the mounting sleeve 26b, preferably at equal angular intervals of 60° in the circumferential direction. The rotary stirring jig 26 is firmly joined to the rotary support rod 27 as a single unit, by attaching the mounting sleeve 26b to one end 27a of the rotary support rod 27 and fixing it in place by welding or the like, thereby forming multiple stirring rods 26a, preferably a total of six stirring rods 26a, which are positioned in the radial direction with three rods offset from each other at two locations in the axial direction X, as described above.
[0033] Furthermore, in this embodiment, as shown in Figure 2, a rotation prevention rod 31 can be attached in a state where it extends parallel to the cylindrical reciprocating rod 21, preferably with one end 31a connected to the partition plate 20 and slidably passing through the end closing plate 17 with the other end 31b protruding to the outside of the end closing plate 17. This makes it possible to effectively prevent the cylindrical reciprocating rod 21 and the partition plate 20 from rotating together when the stirring rod 26a of the rotary stirring jig 26 is rotated via the rotary support rod 27 by the rotation operation of the rotary operation unit 28.
[0034] Furthermore, in this embodiment, an additive supply pipe (not shown) capable of supplying additives to the simulated earth pressure chamber 11 can preferably be connected to the earth pressure chamber cylindrical body 12 and attached, for example, via a multi-purpose valve 33 (see Figure 3) attached to the outer circumference of the earth pressure chamber cylindrical body 12. This makes it possible to add and mix additives to the mud filled in the simulated earth pressure chamber 11 as needed, thereby appropriately adjusting the fluidity of the mud.
[0035] Furthermore, in this embodiment, a water tank 32 for storing water supplied to the simulated earth pressure chamber 11 can preferably be installed adjacent to the earth pressure chamber cylindrical body 12 (see Figure 1). This makes it possible to supply water to the mud filled in the simulated earth pressure chamber 11 as needed to adjust the fluidity of the mud or to adjust the water pressure inside the simulated earth pressure chamber 11. The water stored in the water tank 32 can be supplied to the simulated earth pressure chamber 11, for example, through valves or supply piping connected to the simulated partition plate 13 or end closing plate 17 of the earth pressure chamber cylindrical body 12. In addition to being supplied to the simulated earth pressure chamber 11 by the head difference between the water tank 32 and the simulated earth pressure chamber 11, the water stored in the water tank 32 can also be supplied as pressurized water to the earth pressure chamber cylindrical body 12 or the simulated earth pressure chamber 11 by providing a pressure pump, for example.
[0036] To conduct a test using the simulated earth pressure balance shield tunneling machine simulation device 10 of this embodiment, which has the above-described configuration, prior to actual excavation work using the earth pressure balance shield tunneling machine, in order to understand in advance management items such as the pressure applied to the mud due to the extension of the shield jack, the intake of excavated soil, the flow state of the mud, and the discharge state of the mud via the screw conveyor, depending on the geological conditions of the ground to be excavated, for example, as shown in Figure 5(a), the piston rod 23b of the telescopic jack 23 is fully extended, preferably making the area of the simulated earth pressure chamber 11 between the partition plate 20 and the simulated bulkhead plate 13 the widest possible. Furthermore, a fixing sleeve 34 with a sleeve length of approximately 60 mm is interposed between the support base 22 and the joint base 28a of the rotation operation unit 28, so that the rotary stirring jig 26, which is attached to one end 27a of the rotary support rod 27, protrudes as far as possible relative to the partition plate 20, which is modeled after a cutter plate and is attached to one end 21a of the cylindrical reciprocating rod 21. In this state, the rotary stirring jig 26 is positioned so that its tip is located in an area close to the simulated partition plate 13, preferably about 150 mm plus several tens of mm away from the tip of the screw blade 15, which protrudes slightly beyond the soil discharge opening 13a to which the simulated screw conveyor 16 is connected.
[0037] Subsequently, in the simulated earth pressure chamber 11 in this state, test mud, adjusted according to the geology of the ground to be excavated, can be introduced into the upper cylindrical body 12b (see Figure 3) using the soil input port. This allows the introduced mud to fill the inside of the earth pressure chamber cylindrical body 12 and the simulated screw conveyor 16 that communicates with it. Here, the test mud to be introduced can be, for example, prepared in advance by adding predetermined additives and a predetermined amount of water to soil collected according to the geology of the ground to be excavated, and mixing it using a known mixing device such as a mixing mixer. Furthermore, if necessary, additives and water can be supplied to the test mud from the multi-purpose valve 33 or water tank 32 to appropriately adjust its physical properties during testing with the simulated test device 10.
[0038] In this embodiment, after filling the simulated earth pressure chamber 11 and the simulated screw conveyor 16 in the simulated test device 10 with test soil, for example, by rotating the rotation operation unit 28 from the fully extended state of the piston rod 23b of the telescopic jack 23 shown in Figure 5(a), the rotating agitator 26 at the tip of the rotating support rod 27 positioned in the simulated earth pressure chamber 11 is rotated circumferentially at a speed similar to the rotation speed of the rotating cutter of the shield tunneling machine to be used, thereby agitating the soil filled in the simulated earth pressure chamber 11. By stirring with the stirring rod 26a and rotating the screw blades 15 at a predetermined rotational speed by the drive mechanism 14b, mud is discharged via the simulated screw conveyor 16. At the same time, the piston rods 23b of the pair of telescopic jacks 23 are simultaneously retracted by approximately 150 mm at a predetermined contraction speed. As shown in Figure 5(b), the partition plate 20, which is modeled after a cutter plate and is attached to one end 21a of the cylindrical retractable rod 21, can be advanced by approximately 150 mm at a predetermined speed toward the simulated bulkhead plate 13. Furthermore, the fluctuations in earth pressure caused by the mud filled in the simulated earth pressure chamber 11 and the simulated screw conveyor 16 during this time can be measured by multiple pressure gauges 18, preferably pressure sensors, attached to the simulated earth pressure chamber 11 and the simulated screw conveyor 16.
[0039] In this embodiment, for example, by retracting a pair of telescopic jacks 23 and advancing a partition plate 20, which mimics a cutter plate, toward a simulated bulkhead plate 13 at a predetermined speed, the measurement results from multiple pressure gauges 18 can be obtained. This makes it possible to simulate the pressure applied to the mud and the intake of excavated soil when the shield tunneling machine is actually advanced by the extension of the shield jacks, and to predict the impact of these management items on actual excavation work using a mud pressure balance shield tunneling machine. Furthermore, in this embodiment, for example, in the region adjacent to the soil discharge opening 13a of the simulated bulkhead plate 13 to which the simulated screw conveyor 16 is connected, by obtaining measurement results from multiple pressure gauges 18 when the mud filled in the simulated earth pressure chamber 11 is stirred with a stirring rod 26a and sent to the simulated screw conveyor 16, it becomes possible to simulate the situation in which the mud is stirred and fluidized by the rotation of a cutter plate with a stirring rod inside the earth pressure chamber of the shield tunneling machine, and it becomes possible to predict the influence of the mud flow state during actual excavation work by the mud pressure shield tunneling machine. Furthermore, in this embodiment, for example, by obtaining measurement results from multiple pressure gauges 18 when the screw blades 15 are rotated at a predetermined speed in relation to the forward speed of the partition plate 20 due to the contraction of a pair of telescopic jacks 23 and mud is discharged by the simulated screw conveyor 16, it becomes possible to simulate the situation in which mud is discharged from the earth pressure chamber via the screw conveyor when the shield tunneling machine is actually advanced by the extension of the shield jacks. This makes it possible to predict the impact on the formation of a watertight plug by stable mud inside the screw conveyor when mud is discharged from the earth pressure chamber during actual excavation work using a mud pressure shield tunneling machine.
[0040] As a result, the earth pressure balance shield tunneling machine simulation device 10 of this embodiment makes it possible to simulate and reproduce management items such as the pressure applied to the mud due to the extension of the shield jacks, the intake of excavated soil, the flow state of the mud, and the discharge of mud via the screw conveyor, prior to actual excavation work using the earth pressure balance shield tunneling machine, and to predict the impact of these management items.
[0041] Furthermore, in this embodiment, as shown in Figures 5(a) to (e), Figures 6(a) to (e), and Figures 7(a) to (d), preferably, one or more spacer pipes having a predetermined sleeve length are interposed between the support base portion 22 to which a pair of telescopic jacks 23 are connected and the rotation operation portion 28 attached to the other end 27b of the rotation support rod 27, so as to be able to adjust the protruding length of the rotary stirring jig 26 from the partition plate 20 in the simulated earth pressure chamber 11. For example, four spacer pipes 35a, 35b, 35c, and 35d, each with a sleeve length of 150 mm, are detachably attached to the rotation support rod 27. As a result, the simulated test device 10 moves the rotary stirring jig 26, which is integrally attached to one end 27a of the rotary support rod 27, back and forth in a width of 150 mm in the area close to the simulated bulkhead plate 13, while simultaneously advancing the partition plate 20, which is attached to one end of the cylindrical advance-retract rod 21, from the position closest to the end closing plate 17 in the earth pressure chamber cylindrical body 12 (see Figure 5(a)) to the position close to the simulated bulkhead plate 13 (see Figure 7(d)), for example, in 150 mm increments for a total of 600 mm. During this time, it is possible to continuously conduct tests using similar test mud corresponding to the geology of the ground to be excavated, prior to actual excavation work by the earth pressure balance shield tunneling machine, to grasp in advance control items such as the pressure applied to the mud due to the extension of the shield jacks, the intake of excavated soil, the flow state of the mud, and the discharge state of the mud via the simulated screw conveyor 16.
[0042] In other words, in this embodiment, as described above, test mud is filled into the simulated earth pressure chamber 11 and the simulated screw conveyor 16, and as shown in Figure 5(a), the piston rod 23b of the telescopic jack 23 is fully extended, and while measuring the fluctuation of earth pressure due to the filled mud with multiple pressure gauges 18, the mud is stirred with the stirring rod 26a, and while discharging the mud via the simulated screw conveyor 16, the piston rod 23b is retracted to, for example, about 150 mm, and as shown in Figure 5(b), the partition plate 20, which is modeled after a cutter plate, is advanced by, for example, about 150 mm toward the simulated bulkhead plate 13. Once the partition plate 20, which mimics a cutter plate, is advanced, as shown in Figure 5(c), while maintaining the positions of the piston rod 23b of the telescopic jack 23, the support base 22, the cylindrical reciprocating rod 21, and the partition plate 20, the fixing sleeve 34 to the support base 22 is released, and the rotating operation unit 28, together with the rotating support rod 27 and the rotating stirring jig 26 at one end 27a thereof, is preferably pulled out by about 150 mm in the axial direction X of the earth pressure chamber cylindrical body 12, away from the simulated screw conveyor 16.
[0043] As a result, a gap of approximately 150 mm is maintained between the fixing sleeve 34, which is rotatably attached to the joint base 28a of the extended rotating operating section 28, and the support base 22. Therefore, as shown in Figure 5(d), the first spacer pipe 35a can be attached to and fixed to the rotating support rod 27 in this gap. The first spacer pipe 35a can be easily attached to the rotating support rod 27 by, for example, sandwiching the rotating support rod 27 from both sides with the split members that constitute the first spacer pipe 35a, and joining these split members as a single unit. The attached first spacer pipe 35a is then joined to the support base 22 and the fixing sleeve 34 via, for example, the joint flanges at both ends, thereby fixing it together with the fixing sleeve 34 while maintaining a predetermined gap between the joint base 28a of the rotating operating section 28 and the support base 22. Furthermore, this ensures that the rotating operating section 28, the rotating support rod 27 and the rotating stirring jig 26 joined thereto, are rotatably fixed to the support base section 22 and the cylindrical reciprocating rod 21, while remaining movable in the axial direction X by the extension of the piston rod 23b of the telescopic jack 23.
[0044] Once the first spacer pipe 35a is fixed together with the fixing sleeve 34 between the joint base 28a and the support base 22 of the rotating operation unit 28, as shown in Figure 5(e), while measuring the fluctuations in earth pressure due to the filled mud with multiple pressure gauges 18, the piston rod 23b of the telescopic jack 23 is further retracted to, for example, about 150 mm, and the mud is stirred by the stirring rod 26a, while the mud is discharged via the simulated screw conveyor 16, the partition plate 20, which mimics a cutter plate, is further advanced to, for example, about 150 mm toward the simulated bulkhead plate 13.
[0045] After further advancing the partition plate 20, which mimics a cutter plate, as shown in Figure 6(a), while maintaining the positions of the piston rod 23b of the telescopic jack 23, the support base 22, the cylindrical reciprocating rod 21, and the partition plate 20, the fixing of the first spacer pipe 35a to the support base 22 is released, and the rotation operation unit 28, together with the rotation support rod 27 and the rotation stirring jig 26 at one end 27a thereof, is preferably pulled out by about 150 mm in the axial direction X of the earth pressure chamber cylindrical body 12, away from the simulated screw conveyor 16.
[0046] As a result, a gap of approximately 150 mm is maintained between the first spacer pipe 35a, which is attached to the joint base 28a of the extended rotating operating section 28 together with the fixing sleeve 34, and the support base section 22. Therefore, as shown in Figure 6(b), the second spacer pipe 35b can be attached to and fixed to the rotating support rod 27 in this gap. In this way, the rotating operating section 28, the rotating support rod 27 and the rotating stirring jig 26 joined thereto are rotatably fixed to the support base section 22 and the cylindrical retractable rod 21, so that they can move axially X by the extension of the piston rod 23b.
[0047] Once the second spacer pipe 35b is fixed together with the fixing sleeve 34 and the first spacer pipe 35a between the joint base 28a and the support base 22 of the rotating operation unit 28, as shown in Figure 6(c), while measuring the fluctuations in earth pressure due to the filled mud with multiple pressure gauges 18, the piston rod 23b of the telescopic jack 23 is further retracted to, for example, about 150 mm, the mud is stirred by the stirring rod 26a, and the mud is discharged via the simulated screw conveyor 16, while the partition plate 20, which mimics a cutter plate, is further advanced to, for example, about 150 mm toward the simulated bulkhead plate 13.
[0048] After further advancing the partition plate 20, which mimics a cutter plate, as shown in Figure 6(d), while maintaining the positions of the piston rod 23b of the telescopic jack 23, the support base 22, the cylindrical reciprocating rod 21, and the partition plate 20, the fixing of the second spacer pipe 35b to the support base 22 is released, and the rotation operation unit 28, together with the rotation support rod 27 and the rotation stirring jig 26 at one end 27a thereof, is preferably pulled out by about 150 mm in the axial direction X of the earth pressure chamber cylindrical body 12, away from the simulated screw conveyor 16.
[0049] As a result, a gap of approximately 150 mm is maintained between the second spacer pipe 35b, which is attached to the joint base 28a of the extended rotating operating section 28 together with the fixing sleeve 34 and the first spacer pipe 35a, and the support base section 22. Therefore, as shown in Figure 6(e), the third spacer pipe 35c can be attached to and fixed to the rotating support rod 27 in this gap. In this way, the rotating operating section 28, the rotating support rod 27 and the rotating stirring jig 26 joined thereto are rotatably fixed to the support base section 22 and the cylindrical retractable rod 21, so that they can move axially X by the extension of the piston rod 23b.
[0050] Once the third spacer pipe 35c is fixed together with the fixing sleeve 34, the first spacer pipe 35a, and the second spacer pipe 35b between the joint base 28a and the support base 22 of the rotating operation unit 28, as shown in Figure 7(a), while measuring the fluctuations in earth pressure due to the filled mud with multiple pressure gauges 18, the piston rod 23b of the telescopic jack 23 is further retracted to, for example, about 150 mm, and the mud is stirred with the stirring rod 26a, while the mud is discharged via the simulated screw conveyor 16, the partition plate 20, which mimics a cutter plate, is further advanced to, for example, about 150 mm toward the simulated bulkhead plate 13.
[0051] After further advancing the partition plate 20, which mimics a cutter plate, as shown in Figure 7(b), while maintaining the positions of the piston rod 23b of the telescopic jack 23, the support base 22, the cylindrical reciprocating rod 21, and the partition plate 20, the fixing of the third spacer pipe 35c to the support base 22 is released, and the rotation operation unit 28, together with the rotation support rod 27 and the rotation stirring jig 26 at one end 27a thereof, is preferably pulled out by about 150 mm in the axial direction X of the earth pressure chamber cylindrical body 12, away from the simulated screw conveyor 16.
[0052] As a result, a gap of approximately 150 mm is maintained between the third spacer pipe 35c, which is attached to the joint base 28a of the extended rotating operating section 28 along with the fixing sleeve 34, the first spacer pipe 35a, and the second spacer pipe 35b, and the support base section 22. Therefore, as shown in Figure 7(c), the fourth spacer pipe 35d can be attached to and fixed to the rotating support rod 27 in this gap. As a result, the rotating operating section 28, the rotating support rod 27 and the rotating stirring jig 26 attached to it are rotatably fixed to the support base section 22 and the cylindrical retractable rod 21, while being movable in the axial direction X by the extension of the piston rod 23b.
[0053] Once the fourth spacer pipe 35d is fixed together with the fixing sleeve 34, the first spacer pipe 35a, the second spacer pipe 35b, and the third spacer pipe 35c between the joint base 28a and the support base 22 of the rotating operation unit 28, as shown in Figure 7(d), while measuring the fluctuations in earth pressure due to the filled mud with multiple pressure gauges 18, the piston rod 23b of the telescopic jack 23 is further retracted to, for example, about 150 mm, and the mud is stirred by the stirring rod 26a, while the mud is discharged via the simulated screw conveyor 16, the partition plate 20, which mimics a cutter plate, is further advanced to, for example, about 150 mm toward the simulated bulkhead plate 13.
[0054] As a result, with the mud pressure balance shield tunneling machine simulation device 10 of this embodiment, while moving the rotary stirring jig 26 back and forth in a 150 mm width in the area adjacent to the simulated bulkhead plate 13, and while advancing the partition plate 20, which simulates a cutter plate, by a total of 600 mm at 150 mm intervals, it becomes possible to efficiently conduct tests in advance to understand management items such as the pressure applied to the mud due to the extension of the shield jack 23, the intake of excavated soil, the flow state of the mud, and the discharge state of the mud via the screw conveyor 16.
[0055] It should be noted that the present invention is not limited to the above embodiments and can be modified in various ways. For example, it is not always necessary to provide a fixed stirring rod that protrudes radially inward in the portion of the earth pressure chamber cylindrical body that is close to the simulated partition wall plate, nor is it always necessary to provide an anti-rotation rod to prevent the earth pressure chamber cylindrical body from rotating together.
[0056] 10. Simulation test device for a mud pressure shield tunneling machine. 11. Simulated Earth Pressure Chamber 12. Earth pressure chamber cylindrical body 12a Joining flange 12b Upper cylindrical body 12c Lower cylindrical body 12d Peephole 13 Simulated bulkhead plate 13a Soil removal opening 14 Outer cylindrical body 14a Connection part 14b Drive mechanism 14c gate valve 14d Soil discharge port 15 Screw blades 16 Simulated Screw Conveyor 17 End closure plate 18. Pressure gauge (pressure sensor) 20 partition plates 21 Cylindrical retractable rod 21a One end 21b Other end 22 Support base part 22a Connecting ribs 22b Strip-shaped plate 22c End joint longitudinal rib 22d back plate 23 Telescopic Jack 23a Electric Cylinder 23b Piston rod 23c Tip 26 Rotary stirring jig 26a Stirring rod 26b Mounting Sleeve 27 Rotating support rod 27a One end 27b Other end 28 Rotary operation section 28a Joint base 28b Overhanging rod 28c Intermediate connecting rod 29 Fixed stirring bar 30 Bearing part 31 Anti-rotation rod 31a One end 31b Other end 32 water tanks 33 Multipurpose Valve 34 Fixing sleeves 35a, 35b, 35c, 35d Spacer tubes 50 Support frame section 51 Casters 52 Stopper Legs 52a Adjusting bolt X-axis direction
Claims
1. A simulated test apparatus for an earth pressure balance shield tunneling machine, for evaluating the properties of the excavated soil mud, which is mixed with additives in the earth pressure chamber and then taken into a screw conveyor for discharge. The system comprises a cylindrical earth pressure chamber into which a simulated earth pressure chamber is formed, into which the soil to be evaluated is filled; a simulated partition plate joined to the cylindrical earth pressure chamber, with one end opening closed; a simulated screw conveyor to which one end of an outer cylindrical body is joined to the soil discharge opening of the simulated partition plate, and in which screw blades are rotatably housed inside the outer cylindrical body; a partition plate positioned to slide along the inner circumferential surface of the cylindrical earth pressure chamber and to move back and forth in the axial direction of the cylindrical earth pressure chamber; and a rotating stirring jig rotatably positioned in the simulated earth pressure chamber, with a stirring rod protruding radially outward, in the inner region of the cylindrical earth pressure chamber between the partition plate and the simulated partition plate, which serves as the simulated earth pressure chamber. The partition plate slides through the center of an end-closing plate, which is joined to close the other end opening of the earth pressure chamber cylinder, and is joined to one end of a cylindrical retractable rod that extends in the axial direction of the earth pressure chamber cylinder. The other end of the cylindrical retractable rod is connected to a support base to which it is driven by an expandable jack, causing the earth pressure chamber cylinder to move back and forth in the axial direction. The rotary stirring jig is joined to one end of a rotary support rod that is inserted through the cylindrical reciprocating rod and protrudes into the simulated earth pressure chamber, and is rotated by a rotation operation unit attached to the other end of the rotary support rod, which extends axially beyond the support base, causing it to rotate inside the simulated earth pressure chamber filled with mud.
2. A simulated test device for a soil pressure shield excavator according to claim 1, wherein a plurality of pressure gauges are mounted on the outer cylindrical body of the simulated screw conveyor at predetermined intervals in the longitudinal direction, facing into the interior of the outer cylindrical body.
3. The simulated test apparatus for a mud pressure shield excavator according to claim 1 or 2, wherein the telescopic jacks that move the partition plate forward and backward in the axial direction of the earth pressure chamber cylinder are connected to the ends on both sides of the support base to which the other end of the cylindrical moving rod is joined, and a pair of them are arranged on both sides of the earth pressure chamber cylinder.
4. A simulated test device for a mud pressure shield excavator according to claim 1 or 2, wherein a fixed stirring rod is attached to the portion of the earth pressure chamber cylindrical body adjacent to the simulated partition wall plate, and protrudes radially inward into the simulated earth pressure chamber.
5. A simulated earth pressure shield excavator test apparatus according to claim 1 or 2, wherein one or more spacer pipes having a predetermined axial length are detachably attached to the rotating support rod, interposed between the support base and the rotation operation unit to adjust the protrusion length of the rotary stirring jig from the partition plate in the simulated earth pressure chamber.
6. A simulated test apparatus for a soil pressure shield excavator according to claim 1 or 2, wherein a rotation prevention rod is attached in a state where one end is connected to the partition plate, the other end is slidably penetrating the end closing plate and protruding to the outside of the end closing plate, and the rod is extended parallel to the cylindrical reciprocating rod.
7. A simulated test apparatus for a mud pressure shield excavator according to claim 1 or 2, wherein an additive supply pipe capable of supplying additives to the simulated earth pressure chamber is attached to the cylindrical body of the earth pressure chamber.
8. A simulated earth pressure shield tunneling machine simulation device according to claim 1 or 2, wherein a water tank for storing water supplied to the simulated earth pressure chamber is installed adjacent to the cylindrical body of the earth pressure chamber.