Simulated shield tunnel screw conveyor

Abstract

This invention relates to the field of shield tunneling testing technology, and more particularly to a simulated shield tunneling screw conveyor, comprising a base, an outer cylinder, a lifting assembly, a screw, a pressure monitoring assembly, and a drive unit. The outer cylinder is angle-adjustably mounted on the base via the lifting assembly, which is connected to the outer cylinder and configured to adjust the angle of the outer cylinder. The screw is axially disposed inside the outer cylinder, with its first end extending from the inlet of the outer cylinder. The screw is composed of multiple detachably connected screw segments. The pressure monitoring assembly is installed inside the outer cylinder to monitor pressure changes within the outer cylinder. The drive unit is detachably connected to the second end of the screw and is configured to drive the screw to rotate. This simulated shield tunneling screw conveyor enables studies on the adaptability of the screw conveyor's structure to geological environments or improved soil, providing technical guidance for actual construction.

Description

Technical Field

[0001] This invention relates to the field of tunnel boring machine (TBM) testing technology, and more particularly to a simulated TBM screw conveyor. Background Technology

[0002] The key to earth pressure balance shield tunneling is the realization of earth pressure balance. In order to achieve pressure balance inside and outside the earth chamber, the industry usually adopts the method of soil improvement to help the screw conveyor form a high standard of "soil plug effect", that is, to improve the "pressure holding capacity" of the screw conveyor through soil improvement.

[0003] In fact, the reason why the screw conveyor can form the "soil plug effect" (that is, have pressure holding capacity) is that it relies on the weight of the slag itself and the friction between the slag and the screw, blades and the screw conveyor cylinder wall to resist the water and soil pressure in the soil chamber, so that the pressure value gradually decreases from the inlet to the outlet, and decreases to zero or a small value at the outlet, so that the slag discharge and conveying process can be stable and controllable, and pressure balance at the tunneling face can be achieved.

[0004] It can be seen that, in addition to the properties of the slag itself, the pressure-holding capacity of the screw conveyor is also affected by the screw conveyor's own structure, such as the inclination angle parameter, screw pitch, and screw speed. The higher the inclination angle parameter, the smaller the screw pitch, and the lower the screw speed, the better the pressure-holding capacity, but the corresponding conveying capacity will also decrease. At present, there is a lack of research on the adaptability of the screw conveyor's own structure to the geological environment or improved soil, making it difficult to determine the critical value of the screw conveyor to have a high conveying capacity under the premise of forming an effective "soil plug effect," which makes it difficult to provide technical guidance for actual construction. Summary of the Invention

[0005] The purpose of this invention is to provide a simulated shield tunneling screw conveyor that can conduct research on the adaptability of the screw conveyor's own structure to the geological environment or improved soil, and provide corresponding technical guidance for actual construction.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] A simulated shield tunneling screw conveyor includes a base, an outer cylinder, a lifting assembly, a screw, a pressure monitoring assembly, and a drive unit. The outer cylinder is angle-adjustably mounted on the base and has an inlet for soil entry and an outlet for soil discharge. The inlet is located at one axial end of the outer cylinder, and the outlet is located at the bottom of the outer cylinder. The lifting assembly is connected to the outer cylinder and is configured to adjust the angle of the outer cylinder. The screw is axially disposed inside the outer cylinder, with its first end extending from the inlet. The screw is composed of multiple detachably connected screw segments. The pressure monitoring assembly is installed inside the outer cylinder to monitor pressure changes within the outer cylinder. The drive unit is detachably connected to the second end of the screw and is configured to drive the screw to rotate.

[0008] Optionally, the system includes a luffing sleeve, which is fitted over the outer cylinder. The luffing sleeve has a first flange and a second flange at its two axial ends, respectively. The first flange is connected to the mounting flange on the outer cylinder, and the second flange is vertically positioned.

[0009] Optionally, the lifting assembly includes a slide, a support leg, and a bracket. The outer cylinder and the driving component are both fixed on the bracket. The support leg includes a first support leg and a second support leg. The first ends of the first support leg and the second support leg are coaxially hinged to the bottom of the bracket, and the second ends of the first support leg and the second support leg are respectively hinged to two slides provided on the base. At least one of the two slides can slide on the base.

[0010] Optionally, both slides can slide on the base.

[0011] Optionally, it also includes a limiting member that can limit the angle of the outer cylinder when in the locked state.

[0012] Optionally, the limiting member is a fastener, and one of the base and the slide is provided with a plurality of limiting holes for the fastener to be inserted at intervals along the sliding direction of the slide, and the other of the base and the slide is provided with positioning holes for the fastener to be inserted.

[0013] Optionally, the outer cylinder has multiple injection ports.

[0014] Optionally, the outer cylinder is also provided with a transparent observation window.

[0015] Optionally, the driving component is a variable frequency motor, and a torque sensor is provided between the variable frequency motor and the screw.

[0016] Optionally, the pressure monitoring assembly includes a plurality of pressure sensors spaced apart along the axial direction of the outer cylinder.

[0017] The beneficial effects of this invention are as follows: The simulated shield tunneling screw conveyor in this invention can achieve angle adjustment with the base through the lifting component. When used in conjunction with the soil chamber simulation pressurization device, it can realize the adaptability study of different inclination angles and geological environments. The screw is set to be composed of multiple screws that can be detachably connected. By replacing screw sections with different pitches, the adaptability study of different blade pitches and geological environments can be carried out. This enables the screw conveyor to have good pressure holding capacity and strong conveying capacity at the same time, providing corresponding technical guidance for actual construction. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a simulated shield tunneling screw conveyor in an embodiment of the present invention.

[0019] In the diagram, 1. Base; 2. Outer cylinder; 21. Transparent observation window; 22. Inlet; 3. Screw; 4. Luffing sleeve; 5. Lifting assembly; 51. First leg; 52. Second leg; 53. Slide table; 54. Bracket; 6. Drive component; 7. Reducer; 8. Pressure holding ball valve; 9. Torque sensor. Detailed Implementation

[0020] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0021] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0022] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0023] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0024] This invention proposes a simulated shield tunneling screw conveyor that can be used in conjunction with a soil chamber pressurization simulation device (used to simulate a soil chamber and adjust the pressure inside the chamber, including a simulated soil chamber and a mixing component that can mix the soil inside the simulated soil chamber) to study its own influence on pressure holding capacity. The soil chamber pressurization simulation device is not within the scope of this invention and existing soil chamber pressurization simulation devices can be used, which will not be described in detail here.

[0025] Figure 1The diagram shows a simulated shield tunneling screw conveyor according to one embodiment of the present invention. The simulated shield tunneling screw conveyor includes a base 1, a lifting assembly 5, an outer cylinder 2, a screw 3, a drive component 6, and a pressure monitoring assembly. The outer cylinder 2 is angle-adjustably mounted on the base 1 via the lifting assembly 5, which is used to adjust the angle of the outer cylinder 2. The outer cylinder 2 has an inlet for soil entry and an outlet for soil discharge. The inlet is located at one axial end of the outer cylinder 2, and the outlet is located at the bottom of the outer cylinder 2 on the side away from the inlet, where a pressure-holding ball valve 8 is installed. The pressure monitoring assembly is installed... Installed inside the outer cylinder 2 to monitor pressure changes within the outer cylinder 2, the screw 3 is inserted axially into the outer cylinder 2. Its first end protrudes from the inlet of the outer cylinder 2 and extends into the soil chamber pressurization simulation device, while its second end protrudes from the outer cylinder 2 and is detachably connected to a drive unit 6 fixed at the end of the outer cylinder 2 furthest from the inlet. The drive unit 6 is configured to drive the screw 3 to rotate; specifically, a variable frequency motor can be selected. The variable frequency motor can adjust the rotation speed of the screw 3, thereby determining the impact of the screw 3's rotation speed on the pressure-holding capacity of the simulated shield tunnel screw conveyor. A reducer 7 is also connected between the variable frequency motor and the screw 3. Furthermore, the screw 3 is composed of multiple screw segments detachably connected using methods including, but not limited to, key connections.

[0026] The aforementioned simulated shield tunneling screw conveyor has an adjustable outer cylinder 2 relative to the base 1. During the test, the inclination angle of the outer cylinder 2 is adjusted from small to large. By observing the changes in the readings of the pressure monitoring components during the operation of the simulated shield tunneling screw conveyor, the minimum inclination angle parameter at which the simulated shield tunneling screw conveyor can form an effective "soil plug effect" under this geological environment can be obtained, at which point the conveying capacity is strongest. By replacing screw sections at different positions on the screw 3 (in descending order of pitch), and observing the changes in the readings of the pressure monitoring components during the operation of the simulated shield tunneling machine, the maximum pitch at which the simulated shield tunneling screw conveyor can form an effective "soil plug effect" under this geological environment can be obtained. The screw 3 is designed to be composed of multiple detachable screw sections, and only one section needs to be replaced each time, which reduces the test cost of the simulated shield tunneling screw conveyor compared to replacing the entire screw 3. Moreover, by replacing screw sections located at different positions on the screw 3, the impact of screw sections with the same pitch at different positions on the pressure holding capacity of the simulated screw conveyor can be determined.

[0027] The pressure monitoring component includes multiple pressure sensors spaced apart along the axial direction of the outer cylinder 2. The pressure measured by the pressure sensors can be linearly fitted, and the higher the consistency, the better the pressure holding capability.

[0028] To achieve a fixed connection between the simulated shield tunnel screw conveyor and the earth chamber pressurization simulation device, refer to Figure 1As shown, the simulated shield tunneling screw conveyor also includes a variable-amplitude sleeve 4, which is fitted onto the outer cylinder 2. Its two ends are respectively equipped with a first flange and a second flange. The first flange connects to the mounting flange on the outer cylinder 2, and the second flange is a non-circular flange that can be bolted to the wall of the simulated chamber in the soil chamber pressurization simulation device. The variable-amplitude sleeve 4 is replaced according to the adjustment angle of the outer cylinder 2. It is necessary to ensure that when the variable-amplitude sleeve 4 is fitted onto the outer cylinder 2, the first flange is parallel to the mounting flange on the outer cylinder 2, and the second flange is parallel to the wall of the simulated chamber (i.e., in a vertical position).

[0029] The lifting assembly 5 is located on the side of the outer cylinder 2 away from the luffing sleeve 4. The lifting assembly 5 can be a hydraulic cylinder, with both ends of the hydraulic cylinder hinged to the outer cylinder 2 and the base 1 respectively. The angle of the outer cylinder 2 can be adjusted by the extension and retraction of the hydraulic cylinder.

[0030] In this embodiment, the lifting assembly 5 includes a slide 53, support legs, and a bracket 54. The outer cylinder 2 and the driving component 6 are both fixed on the bracket 54. There are two support legs, including a first support leg 51 and a second support leg 52. The first ends of the first support leg 51 and the second support leg 52 are coaxially hinged to the bottom of the bracket 54, and the second ends of the first support leg 51 and the second support leg 52 are respectively hinged to two slides 53 provided on the base 1. At least one of the two slides 53 can slide on the base 1. As one of the slides 53 moves, the included angle between the first support leg 51 and the second support leg 52 of the hinged support legs connected to the slide 53 will change, and the height of the connection point between the outer cylinder 2 and the bracket 54 will naturally change.

[0031] The first leg 51, the second leg 52, and the base 1 can form a stable triangular structure, which can significantly improve the support stability of the outer cylinder 2 compared to using a hydraulic cylinder to adjust the height of the outer cylinder 2.

[0032] Furthermore, since both slides 53 can slide on the base 1, when one slide 53 slides on the base 1, the other slide 53 can move in the opposite direction under the transmission action of the support legs. This configuration avoids the need to adjust the distance between the entire simulated shield tunnel screw conveyor and the soil chamber pressurization simulation device during the test, thus simplifying the operation.

[0033] Understandably, in this embodiment, the sliding direction of the two slides 53 relative to the base 1 does not affect the adjustment of the height of the outer cylinder 2. They can be set at intervals along the projection direction of the outer cylinder 2 on the base 1, at intervals along the projection direction perpendicular to the projection direction of the outer cylinder 2 on the base 1, or at intervals along other directions.

[0034] Meanwhile, the simulated tunnel boring machine screw conveyor also includes limiting components, which include a locked state that restricts the movement of the slide 53 and an unlocked state that does not restrict the movement of the slide 53. In the locked state, the limiting component can limit the angle of the outer cylinder 2, preventing it from changing angle during the operation of the simulated tunnel boring machine screw conveyor.

[0035] The limiting components can be fasteners. One of the base 1 and the slide 53 has multiple limiting holes spaced apart along the sliding direction of the slide 53, while the other has a positioning hole. Fasteners can be inserted into the positioning hole and one of the limiting holes to limit the movement of the slide 53. The fasteners can be bolts or pins. By adjusting the position of the limiting hole into which the fastener is inserted, the position of the slide 53 on the base 1 can be adjusted. It is understood that the number of limiting holes is the same as the number of luffing sleeves 4, with each limiting hole corresponding to one luffing sleeve 4 for connection to the simulated earth chamber, for use in conjunction with the luffing sleeve 4.

[0036] To improve the applicability of the simulated screw conveyor, the outer cylinder 2 is also provided with multiple injection ports 22 for injecting soil modification materials such as bentonite, foam, and polymer. The injection ports 22 can be connected to the storage tank of the external modifier to cooperate with the pressure sensor to establish an effective evaluation of the improvement effect of the same modification material on different adverse strata or the improvement effect of different modification materials on the same strata. This provides technical guidance for the pressure holding characteristics of the screw conveyor in earth pressure shield tunneling, especially in water-rich strata. The simulated screw conveyor in this embodiment also includes a pore water pressure gauge.

[0037] To allow for a direct view of the soil transport within the simulated screw conveyor, a transparent observation window 21 is provided on the outer cylinder 2. Specifically, the transparent observation window 21 can be located on the side of the outer cylinder 2 near the variable amplitude sleeve 4.

[0038] A torque sensor 9 is also installed between the reducer and the screw 3. If the torque measured by the torque sensor 9 suddenly fluctuates and decreases, it indicates that the pressure holding of the simulated shield screw conveyor is unstable.

[0039] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A simulated shield tunneling screw conveyor, characterized in that, include: Base (1); The outer cylinder (2) is installed on the base (1) at an adjustable angle. The outer cylinder (2) has an inlet for soil to enter and an outlet for soil to exit. The inlet is located at one axial end of the outer cylinder (2), and the outlet is located at the bottom of the outer cylinder (2) on the side away from the inlet. A lifting assembly (5) is connected to the outer cylinder (2), and the lifting assembly (5) is configured to adjust the angle of the outer cylinder (2); The screw (3) is arranged axially inside the outer cylinder (2) along the outer cylinder (2). The screw (3) is composed of multiple screw segments that are detachably connected. The first end of the screw (3) passes through the inlet of the outer cylinder (2). A pressure monitoring component is installed inside the outer cylinder (2) to monitor pressure changes inside the outer cylinder (2); A drive member (6) is detachably connected to the second end of the screw (3), and the drive member (6) is configured to drive the screw (3) to rotate; By replacing the screw section at different positions on the screw (3), the reading changes of the pressure monitoring component during the operation of the simulated shield screw conveyor are observed, and the maximum screw pitch that the simulated shield screw conveyor can form an effective "soil plug effect" under this geological environment is obtained. The lifting assembly (5) includes a slide (53), legs, and a bracket (54). The outer cylinder (2) and the driving component (6) are both fixed on the bracket (54). The legs include a first leg (51) and a second leg (52). The first ends of the first leg (51) and the second leg (52) are coaxially hinged to the bottom of the bracket (54). The second ends of the first leg (51) and the second leg (52) are respectively hinged to two slides (53) provided on the base (1). At least one of the two slides (53) can slide on the base (1).

2. The simulated shield tunneling screw conveyor according to claim 1, characterized in that, Includes a variable amplitude sleeve (4), which is sleeved on the outer cylinder (2). The variable amplitude sleeve (4) has a first flange and a second flange respectively at its two axial ends. The first flange is connected to the mounting flange on the outer cylinder (2), and the second flange is vertically arranged.

3. The simulated shield tunneling screw conveyor according to claim 1, characterized in that, Both of the slides (53) are able to slide on the base (1).

4. The simulated shield tunneling screw conveyor according to claim 1, characterized in that, It also includes a limiting member, which can limit the angle of the outer cylinder (2) when locked.

5. The simulated shield tunneling screw conveyor according to claim 4, characterized in that, The limiting member is a fastener. One of the base (1) and the slide (53) is provided with a plurality of limiting holes for the fastener to be inserted at intervals along the sliding direction of the slide (53). The other of the base (1) and the slide (53) is provided with positioning holes for the fastener to be inserted.

6. The simulated shield tunneling screw conveyor according to any one of claims 1-5, characterized in that, The outer cylinder (2) has multiple injection ports (22).

7. The simulated shield tunneling screw conveyor according to any one of claims 1-5, characterized in that, The outer cylinder (2) is also provided with a transparent observation window (21).

8. The simulated shield tunneling screw conveyor according to any one of claims 1-5, characterized in that, The drive component (6) is a variable frequency motor, and a torque sensor (9) is provided between the variable frequency motor and the screw (3).

9. The simulated shield tunneling screw conveyor according to any one of claims 1-5, characterized in that, The pressure monitoring assembly includes multiple pressure sensors spaced apart along the axial direction of the outer cylinder (2).

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