Anti-rotation propulsion piston device and method of use

Abstract

This invention relates to the field of tunnel boring machine (TBM) testing technology, and particularly to an anti-torsion propulsion piston device and its usage method. The anti-torsion propulsion piston device includes a soil hopper, a loading mechanism, and an anti-rotation mechanism. The loading mechanism includes a propulsion piston and a first driving component. The propulsion piston is located inside the soil hopper and is in a sealed sliding fit with it. The first driving component is mounted on a reaction support frame and can drive the propulsion piston to reciprocate along the axial direction of the soil hopper. The anti-rotation mechanism includes an anti-torsion guide column and an anti-rolling part. The anti-torsion guide column is eccentrically positioned in a sliding fit between the propulsion piston and the reaction support frame. The anti-rolling part is located at the end of the propulsion piston facing away from the reaction support frame and can be inserted into the soil to limit and fix the soil. The anti-rotation mechanism can prevent the propulsion piston or the soil from rotating when the cutterhead rotates. The invention also relates to a method of using the anti-torsion propulsion piston device, which can be used in conjunction with a simulated TBM to simulate TBM construction under different geological environments.

Description

Technical Field

[0001] This invention relates to the field of tunnel boring machine testing technology, and in particular to an anti-torsion propulsion piston device and its usage method. Background Technology

[0002] With the development of underground space construction, the quality requirements for shield tunneling are gradually increasing. Shield tunneling is a dynamic process involving a complex interaction between the machine and the soil. Numerous uncertainties, such as various soil parameters, directly affect the shield-soil interaction process and its mechanical mechanisms. Due to the limitations of the construction environment, it is difficult to directly observe the shield tunneling equipment. Therefore, simulation experiments are often used to study the characteristics of shield tunneling machines during underground tunnel construction. This is undoubtedly a scientific, effective, and cost-efficient method.

[0003] The key to shield tunneling simulation tests lies in employing specific methods to simulate the interaction between the soil layer and the cutterhead, as well as the propulsion of the cutterhead. For example, in a previous application (publication number CN113240999B), the applicant proposed a test device for simultaneous shield tunneling and soil cutting with improved soil. Utilizing the principle of force interaction, a soil hopper is set up, with an active piston at one end and a cutterhead at the other. The active piston pushes the soil within the hopper towards the cutterhead, which then rotates and cuts the soil. The active piston simulates the relative motion between the cutterhead and the soil during shield tunneling, enabling realistic simulation and visualization of the shield tunneling and soil cutting processes. This facilitates the optimization of the shield's adaptability design to geological conditions.

[0004] However, the active piston in the above-mentioned test device may be torn under large uneven loads and torques, and the soil in the soil bin may also be torn under the reaction force of the rotating cutter head, affecting the final experimental results. Summary of the Invention

[0005] One of the objectives of this invention is to provide an anti-torsion propulsion piston device that can prevent the piston and soil from twisting, thus ensuring the smooth progress of propulsion experiments.

[0006] An anti-torsion propulsion piston device includes a reaction support frame, a soil hopper, a loading mechanism, and an anti-rotation mechanism. The soil hopper is fixed on the reaction support frame and is configured as a cylindrical structure with open ends. The loading mechanism includes a propulsion piston and a first driving component. The propulsion piston is located inside the soil hopper and is in a sealed sliding fit with the soil hopper. The first driving component is mounted on the reaction support frame and can drive the propulsion piston to reciprocate along the axial direction of the soil hopper. The anti-rotation mechanism includes an anti-torsion guide post and an anti-rolling part. The anti-torsion guide post is eccentrically located at the end of the propulsion piston facing the reaction support frame and extends out of the reaction support frame, slidingly fitting with the reaction support frame. The anti-rolling part is located at the end of the propulsion piston facing away from the reaction support frame and can be inserted into the soil to limit and fix the soil.

[0007] Optionally, the anti-roll portion is configured as a strip-shaped protrusion.

[0008] Optionally, the anti-roll portion is detachably connected to the propulsion piston, and an airbag is detachably connected to one end face of the propulsion piston where the anti-roll portion is located.

[0009] Optionally, it also includes a base, which includes a fixed skid frame and a movable skid frame, the reaction support frame being disposed on the movable skid frame, and the movable skid frame being slidably disposed on the fixed skid frame.

[0010] Optionally, the reaction support frame is rotatably connected to the movable skid frame.

[0011] Optionally, the first driving element is provided in multiple forms and its output ends are evenly distributed on the propulsion piston.

[0012] Optionally, the soil silo is detachably connected to the reaction support frame.

[0013] Optionally, the thrust piston is provided with an annular receiving groove in the circumferential direction to accommodate a lip seal ring, and the receiving groove is connected to an oil injection port.

[0014] Optionally, the end of the propulsion piston facing away from the reaction support frame is also connected to an annular, elastic sealing ring, which is always in contact with the soil hopper.

[0015] The second objective of this invention is to provide a method for using an anti-torsion propulsion piston device, which can be used in conjunction with a simulated tunnel boring machine (TBM) to simulate TBM construction under different geological conditions. The simulated TBM includes a cutterhead that is rotatably and sealed to the soil hopper. The anti-roll portion of the anti-torsion propulsion piston device is configured as a strip-shaped protrusion and detachably connected to the propulsion piston. An airbag is detachably connected to one end face of the propulsion piston where the anti-roll portion is located. The base includes a fixed skid frame and a movable skid frame. A reaction support frame is mounted on the movable skid frame, and the movable skid frame is slidably mounted on the fixed skid frame. The reaction support frame is rotatably connected to the movable skid frame. The method of using the anti-torsion propulsion piston device includes the following steps:

[0016] Prepare test soil according to the strata to be simulated. The simulated strata include one or more of hard rock strata, soft soil strata, and composite strata.

[0017] Adjust the position and angle of the soil silo so that the end away from the reaction support frame has an upward opening. After filling the soil silo with the test soil, apply a load to the test soil according to the simulated geological environment to establish preliminary confining pressure, and then unload.

[0018] The soil hopper is reversed and moved to connect with the cutter head, sealing the opening of the soil hopper, and the propulsion piston is pushed to rotate the cutter head.

[0019] Optionally, when the test soil being filled is a rock block simulating hard rock, the rock block is first processed into a cylindrical geometric shape consistent with the radial cross-section of the soil silo, and then grooved to fit with the anti-rolling part; when the test soil being filled is soft soil simulating soft soil strata and the soft soil does not have self-stability, after applying a load to establish preliminary confining pressure and unloading, a layer of cohesive soil or a layer of adhesive is added to the end face of the soft soil away from the propulsion piston; when the test soil being filled is soft soil and rock blocks simulating composite strata and the soft soil does not have self-stability, after applying a load to establish preliminary confining pressure and unloading, a layer of cohesive soil or a layer of adhesive is added to the end face of the soft soil away from the propulsion piston.

[0020] Optionally, when the test soil being filled is soft soil and rock blocks simulating a composite stratum, the anti-roll section of the upper part of the propulsion piston is replaced with an air bladder, and air or liquid is injected into the air bladder to ensure that the soft soil and rock blocks can be synchronously pushed by the propulsion piston.

[0021] The beneficial effects of this invention are as follows: This invention utilizes the principle of force interaction to simulate the propulsion of the cutterhead during shield tunneling by installing a sliding anti-torsion propulsion piston within the soil hopper. This allows for direct observation of the soil conditions within the hopper. Simultaneously, an anti-torsion mechanism is added to the propulsion piston, comprising an anti-torsion guide column and an anti-rolling part. The anti-torsion guide column and anti-rolling part respectively prevent the propulsion piston and the soil from rotating or rolling under the action of the cutterhead rotation, making the simulation process closer to real working conditions. The simulation test results obtained using this anti-torsion propulsion piston device can more effectively reflect the characteristics of the actual construction process. This invention also includes a method for using the anti-torsion propulsion piston device. This method can be used in conjunction with a simulated shield tunneling machine to simulate the cutterhead propulsion of the shield tunneling machine under different strata, which helps optimize the adaptability design of the shield tunneling machine to the geology. Attached Figure Description

[0022] Figure 1 This is a three-dimensional structural diagram of the anti-torsion propulsion piston device in an embodiment of the present invention;

[0023] Figure 2 This is a side view of the anti-torsion propulsion piston device in an embodiment of the present invention;

[0024] Figure 3 This is a front view of the anti-torsion propulsion piston device in an embodiment of the present invention;

[0025] Figure 4 This is a rear view of the anti-torsion propulsion piston device in an embodiment of the present invention.

[0026] In the diagram, 1 is the base; 11 is the fixed skid mount; 12 is the movable skid mount; 13 is the column support; 2 is the reaction support frame; 21 is the second reinforcing rib; 22 is the second flange; 3 is the soil silo; 31 is the first flange; 32 is the first reinforcing rib; 4 is the propulsion piston; 5 is the first driving component; 6 is the anti-torsion guide column; 7 is the anti-roll part; 8 is the second driving component; and 9 is the third driving component. Detailed Implementation

[0027] 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.

[0028] 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.

[0029] 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.

[0030] 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.

[0031] To make the simulated tunnel boring machine (TBM) construction process more closely resemble the actual construction process, the inventors have improved upon the technical solutions proposed in the background section by proposing an anti-torsion propulsion piston device. This device can work in conjunction with a simulated TBM to simulate the propulsion action of the soil layer relative to the TBM. The simulated TBM can be a scaled-down version of the actual TBM and includes a simulated soil chamber structure. The simulated soil chamber structure contains a rotatable cutterhead that is sealed and rotatably connected to the soil hopper. The cutterhead is equipped with blades arranged according to actual working conditions to simulate soil cutting under real geological conditions. The anti-torsion propulsion piston device includes a soil hopper, a propulsion piston, and an anti-rotation mechanism. The propulsion piston is located at one end of the soil hopper, while the simulated soil chamber structure is located at the other end. When the propulsion piston moves within the soil hopper, the cutterhead moves relative to the soil within the hopper, simulating the TBM tunneling process. The anti-rotation mechanism is located on the propulsion piston, preventing both the piston from rotating around its own axis within the soil hopper and the soil within the hopper from rotating.

[0032] Figure 1-4The anti-torsion propulsion piston device shown in one embodiment of the present invention includes a base 1, a reaction support frame 2, a soil silo 3, a loading mechanism, and an anti-torsion mechanism. The base 1 serves as a basic component, providing an installation base for other functional components. The soil silo 3 is configured as a cylindrical structure with openings at both ends along the axial direction. The reaction support frame 2 is mounted on the base 1 and is configured as a cylindrical structure with one end open. The open end of the reaction support frame 2 is coaxially connected to the soil silo 3. The loading mechanism includes a propulsion piston 4 and a first driving member 5. The propulsion piston 4 is located inside the soil silo 3 and is in a sealed sliding fit with the soil silo 3. The first driving member 5 is mounted on the reaction support frame 2 and can push the propulsion piston 4 to reciprocate along the axial direction of the soil silo 3. The anti-rotation mechanism includes an anti-torsion guide post 6 and an anti-rolling part 7. The anti-torsion guide post 6 is eccentrically positioned at the end of the push piston 4 facing the reaction support frame 2 and extends through the reaction support frame 2 to make over-fitting contact with it. The anti-rolling part 7 is positioned at the end of the push piston 4 facing away from the reaction support frame 2 and can be inserted into the soil to limit and fix the soil, preventing the soil from rolling relative to the push piston 4.

[0033] In the actual construction process of shield tunneling, it is often affected by underground confined water. A confined water injection port is also set on the soil silo 3. Water is injected into the soil silo 3 through the confined water injection port to simulate confined water, so as to study the impact of confined water on shield tunneling.

[0034] In this embodiment, the anti-torsion propulsion piston device uses a propulsion piston that moves within the soil hopper 3 to move the soil, simulating the relative motion between the soil and the tunnel boring machine (TBM). This allows for direct observation of the soil within the hopper. The anti-torsion propulsion piston device adds an anti-rotation mechanism to the existing structure. This mechanism includes an anti-torsion guide column 6 and an anti-rolling part 7. The anti-torsion guide column 6 is fixed to the propulsion piston 4. Under the constraint of the reaction support frame 2, the anti-torsion guide column 6 ensures that the propulsion piston 4 can only move in a straight line within the soil hopper 3. The anti-rolling part 7 targets the soil within the soil hopper 3. Given that the propulsion piston 4 can only move in a straight line, the soil interlocking with the propulsion piston 4 can also only move in a straight line. This more closely resembles the motion and force conditions between the TBM and the soil during actual TBM construction. Therefore, the simulation test results obtained using this anti-torsion propulsion piston device can more effectively reflect the characteristics of the actual construction process. For example, soil pressure sensors and pore water pressure sensors can be installed on the propulsion piston to monitor the mechanical response of the soil in the soil hopper in real time during the propulsion process of the propulsion piston, so as to obtain the most favorable parameters in the cutterhead shield construction process. It can also be used in conjunction with a simulated shield machine to simulate underground obstacles, such as changes in thrust and torque in shield construction parameters under conditions of isolated boulders or sudden changes in strata (the thrust change is obtained by the pressure sensor in front of the cutterhead panel, and the torque change is obtained by the main drive torque sensor of the cutterhead).

[0035] refer to Figure 3 As shown, to achieve a seamless connection with the soil, the anti-rollover part 7 can be configured as a strip-shaped groove on the propulsion piston 4. Correspondingly, the soil in the soil hopper 3 facing the propulsion piston 4 has a strip-shaped protrusion that engages with the strip-shaped groove. Alternatively, the anti-rollover part 7 can be configured as a strip-shaped protrusion fixed on the propulsion piston 4, with the soil in the soil hopper 3 facing the propulsion piston 4 having a strip-shaped groove that engages with the strip-shaped protrusion. Obviously, setting a groove on the soil is much easier than setting a protrusion. Therefore, in this embodiment, the anti-rollover part 7 is configured as a strip-shaped protrusion and is connected to the propulsion piston 4 using detachable connections, including but not limited to screw connections and plug connections. When the soil is loaded into the soil hopper 3, the position of the propulsion piston 4 can be adjusted according to the groove on the soil. For example, the anti-rollover part 7 is screwed to the propulsion piston 4, and multiple anti-rollover parts 7 are fixed radially along the end face of the propulsion piston 4 facing the simulated tunnel boring machine. It is understandable that the lengths of different anti-roll parts 7 can be the same or different, and no specific restrictions are imposed here.

[0036] It is understandable that the anti-roll section 7 in the aforementioned anti-torsion propulsion piston device is mainly applicable to hard rock strata and composite strata with a soft upper layer and a hard lower layer. For soft soil strata, the stratum itself has a viscous property, and the adhesion between the soil hopper 3 and the soft soil stratum is sufficient to prevent the soft soil stratum from rotating as a whole. The stratum itself has a non-viscous property, making torque difficult to transmit and preventing overall torsion. Therefore, the anti-torsion propulsion piston device in this embodiment can be applied to the construction simulation of tunnel boring machines under various soil conditions. For composite strata, because the end face of the propulsion piston has high stiffness in contact with the hard rock portion used to simulate the composite stratum, the hard rock will be pushed towards the cutterhead, while the soft soil portion used to simulate the soft soil portion of the composite stratum will be difficult to propel. To address this, an airbag (not shown in the figure) is installed at the end face of the anti-roll section 7 of the propulsion piston 4 corresponding to the soft soil. By pressurizing the airbag, not only can the force imbalance of the propulsion piston 4 be balanced, ensuring its smooth advancement, but it can also add axial compressive force along the soil layer hopper 3 to the soft soil, thereby forming confining pressure and allowing the upper soft soil and lower rock blocks to advance synchronously. In actual shield tunneling, this corresponds to the cutterhead simultaneously cutting the upper soft soil layer and the lower hard rock layer. It is understood that the airbag and the propulsion piston 4 are also detachably connected. When dealing with rock blocks, the airbag can be removed. When dealing with simulated composite soil layers, the anti-roll section 7 of the propulsion piston 4 corresponding to the soft soil portion of the composite soil layer can be removed, and the airbag can be installed on the propulsion piston 4.

[0037] refer to Figure 4As shown, multiple anti-torsion guide posts 6 are provided and evenly distributed on the end face of the piston facing the reaction support frame 2. For example, four anti-torsion guide posts 6 are provided, which are connected to the push piston 4 by flanges and are arranged in a circular pattern on the end face of the push piston 4 to further improve the anti-torsion effect.

[0038] The sealing effectiveness between the soil hopper 3 and the propulsion piston 4 is crucial for studying the impact of pressurized water on tunnel boring machine (TBM) construction. The seal between the propulsion piston 4 and the soil hopper 3 is achieved through a lip seal ring. For example, the propulsion piston 4 has an annular groove circumferentially arranged to accommodate the lip seal ring. Multiple grooves are spaced apart along the axial direction of the propulsion piston 4, and each groove accommodates one lip seal ring. The groove is connected to an oil injection port, which is connected to an external oil injection device. Oil is injected into the groove through the oil injection port, causing the lip of the lip seal ring to deform under hydraulic pressure, thus sealing the lip tightly against the inner wall of the soil hopper 3.

[0039] Furthermore, an annular, elastic sealing ring is connected to one end of the propulsion piston 4 facing away from the reaction force support frame 2. This sealing ring is always in contact with the soil hopper 3. For example, the sealing ring is made of metal and is screwed onto the end face of the piston facing away from the reaction force support frame 2. Its axial cross-section is an arc shape concave towards the piston. After wear, the sealing ring has a certain self-compensation capability due to its elasticity, resulting in a long service life. The sealing ring and the lip seal work together to achieve a double seal between the propulsion piston 4 and the soil hopper 3, providing a good sealing effect.

[0040] Optionally, the soil silo 3 and the reaction support frame 2 are detachably connected to allow for the replacement of soil silos 3 of different lengths, thereby adjusting the propulsion stroke. For example, both ends of the soil silo 3 are provided with a first flange 31, and the end of the reaction support frame 2 connected to the soil silo 3 is provided with a second flange 22. The first flange 31 at one end of the soil silo 3 is connected to the flange of the reaction support frame 2, and the first flange 31 at the other end is connected to the flange of an external simulated soil silo structure. Of course, the detachable connection also facilitates separate cleaning of the soil silo 3 and the reaction support frame 2.

[0041] Depending on the testing requirements, the soil silo 3 can be made of transparent plexiglass for easy observation. To improve structural strength, a first reinforcing rib 32 is sandwiched between the first flanges 31 at both ends of the soil silo 3, which is arranged along the axial direction of the soil silo 3. The two ends of the first reinforcing rib 32 extend to the first flanges 31 at both ends of the soil silo 3, and multiple first reinforcing ribs 32 are arranged at intervals along the circumference of the soil silo 3. A second reinforcing rib 21 is provided between the main body of the reaction support frame 2 and the second flange 22. The second reinforcing rib 21 is triangular.

[0042] To facilitate loading and unloading of material into or out of the soil silo 3, the anti-torsion propulsion piston device and the simulated tunnel boring machine (TBM) must be able to move closer to or further apart. Compared to the movable nature of the simulated TBM, the movement of the anti-torsion propulsion piston device is clearly more convenient (the simulated TBM includes not only the simulated soil silo structure but also structures such as a screw conveyor, making its structure relatively complex and heavy). Therefore, refer to... Figure 1 As shown, the base 1 of the anti-torsion propulsion piston device in this embodiment includes a fixed skid frame 11 and a movable skid frame 12. A reaction support frame 2 is mounted on the movable skid frame 12, which is slidably mounted on the fixed skid frame 11. To achieve automation, a second driving member 8 is also provided on the base 1. The second driving member 8 is connected to the fixed skid frame 11, and its output end is connected to the movable skid frame 12, enabling it to push the movable skid frame 12 to move on the fixed skid frame 11. Specifically, the fixed skid frame 11 is equipped with a slide rail, and the movable skid frame 12 slides along the slide rail under the action of the second driving member 8. The second driving member 8 can also be a hydraulic cylinder.

[0043] Furthermore, the reaction support frame 2 and the movable skid frame 12 are rotatably connected via a rotating shaft. During the simulated shield tunneling process, the soil hopper 3 connected to the reaction support frame 2 is horizontally positioned. During material loading or unloading, the end of the soil hopper 3 furthest from the reaction support frame 2 flips upwards, facilitating loading or unloading. Specifically, the flipping of the reaction support frame 2 is achieved by a third driving component 9. This third driving component 9 can be a rotary motor or a hydraulic cylinder. If a rotary motor is used, its output end is connected to the rotating shaft of the reaction support frame 2. If a hydraulic cylinder is used, one end of the cylinder is hinged to the movable skid frame 12, and the other end is hinged to the reaction support frame 2. In this embodiment, the third driving component 9 is a hydraulic cylinder, with two cylinders located on either side of the reaction support frame 2 to achieve stable flipping of the reaction support frame 2.

[0044] Obviously, when the soil silo 3 and the reaction support frame 2 are rotated, the anti-torsion guide column 6 and the first driving component 5 need to be avoided. That is to say, when the soil silo 3 and the reaction support frame 2 are set horizontally, there is a certain height difference between them and the surface of the movable skid frame 12. For example, the movable skid frame 12 is provided with column supports 13 at both ends of the horizontal radial direction of the reaction support frame 2. The column supports 13 are set as a split structure, including a support part and a clamping part. The clamping part is detachably connected to the top of the support part and together with the support part surrounds the rotating hole to accommodate the rotating shaft. A bearing is provided in the rotating hole. The rotating shaft of the reaction support frame 2 is connected to the bearing, thereby realizing the rotational connection with the column support 13.

[0045] Since the cutterhead advances smoothly during actual construction, the propulsion piston 4 also needs to ensure smooth movement at all points. Specifically, multiple first driving components 5 are used to push the propulsion piston 4, and their output ends act evenly on the propulsion piston 4. Hydraulic cylinders can be used, as they can withstand higher working pressures than pneumatic cylinders and are more suitable for heavy-load applications such as simulating tunnel boring machine construction. In this embodiment, four hydraulic cylinders are provided, connected to the propulsion piston 4 via flanges, and arranged in a circumferential array on the end face of the propulsion piston 4.

[0046] Based on the four-cylinder configuration, this method can also be used to study the synchronization algorithm for the cylinders driving the propulsion piston. By combining geological information and deep learning algorithms, it can achieve synchronous control research that adapts the four cylinders to the geological formation. Different geological formations and different cutterheads will affect the required thrust of the piston, and thus the required cylinder type will also differ. The following calculations determine the required piston thrust for different geological formations and the type of cutterhead in the simulated tunnel boring machine. After the calculations are completed, cylinders are selected based on the required piston thrust, and the load is evenly distributed on the side of the propulsion piston facing away from the cutterhead.

[0047] First, for soft soil strata, there is no need to consider the influence of cutterhead type on piston propulsion.

[0048] The calculation of piston propulsion force mainly includes three parts: 1) the frictional force F1 between the soil and the soil silo; 2) the horizontal earth pressure F2 in the soil silo; and 3) the compressive force F3 on the soil.

[0049] F1=μ×S×P d

[0050]

[0051]

[0052] μ - Coefficient of friction between soil and soil layer silo;

[0053] P d - The pressure at the central axis of the cutterhead in the simulated tunnel boring machine (via pressure sensor) is approximately 1.25 times the pressure of the soil silo (the pressure of the soil silo is set according to the stratum information);

[0054] S - The maximum area of ​​the friction surface during propulsion, S = π × D × L;

[0055] L - Effective advance distance of the soil;

[0056] D - Area dimensions of the propellant piston;

[0057] c - Cohesion of the test soil;

[0058] If the reserve coefficient is taken as k, then the total thrust of the propulsion piston is:

[0059] F n = k*(F1+F2+F3)

[0060] II. For hard rock formations, the piston propulsion force is affected by the soil type and the cutterhead.

[0061] The piston propulsion force calculation mainly includes: 1) the frictional force F1 between the soil and the soil hopper; 2) the horizontal earth pressure F2 in the soil hopper; and 3) the rock-breaking force F4 required by the cutterhead tool.

[0062] F4=p×m

[0063] m - The number of roller cutters on the cutterhead of the simulated tunnel boring machine;

[0064] Calculation of thrust required for p-roll cutter rock breaking - calculated according to the CSM model.

[0065] If the reserve coefficient is taken as k, then the total thrust of the propulsion piston is:

[0066] F n = k*(F1+F2+F4)

[0067] Third, for complex strata, the propulsion force of the hydraulic cylinder is affected by the soil type and the cutterhead.

[0068] The calculation of hydraulic cylinder propulsion force mainly includes: 1) the frictional force F1 between the soil and the soil hopper; 2) the horizontal soil pressure F2 in the soil hopper; 3) the compressive force F3 on the soil; and 4) the rock-breaking force F4 required by the cutter head.

[0069] If the reserve coefficient is taken as k, then the total thrust of the hydraulic cylinder is:

[0070] F n = k*(F1+F2+F3+F4)

[0071] Based on the aforementioned anti-torsion propulsion piston device, this embodiment also provides a method of use, mainly for simulating shield tunneling under different geological conditions, which helps optimize the adaptability design of the shield to the geology. Of course, this method also requires the cooperation of a simulated tunnel boring machine; the specific steps are as follows:

[0072] I. Experimental Preparation

[0073] 1. Check whether the anti-torsion propulsion piston device and the control system of the simulated tunnel boring machine are normal.

[0074] 2. Prepare test soil according to the strata to be simulated. The simulated strata include one of the following: soft soil strata, hard rock strata, and composite strata.

[0075] II. Experimental Procedure

[0076] The position and angle of the soil silo 3 are adjusted by the second drive component 8 and the third drive component 9, so that the end away from the reaction support frame 2 has its opening facing upwards. After filling the soil silo 3 with test soil, a load is applied to the test soil according to the simulated geological environment (shield tunnel burial depth, etc.) to establish preliminary confining pressure, and then the load is unloaded. The specific unloading method can be achieved by using a vertically arranged hydraulic cylinder with a pressure plate, the area of ​​which is consistent with the opening area of ​​the soil silo 3.

[0077] Reverse flip and move to connect the soil hopper 3 with the simulated soil hopper structure and close the opening of the soil hopper 3. Push the propulsion piston 4 and rotate the cutter head. Observe the changes of the required parameters according to different test requirements. After the test, take out the test soil and clean the anti-torsion propulsion piston device.

[0078] It is important to note that when filling the test soil, if the test soil is a rock block simulating hard rock, the rock block needs to be processed into a cylindrical geometry consistent with the radial cross-section of the soil hopper 3, and then grooved to fit with the anti-roll part 7, ensuring that the torque exerted on the rock block by the cutterhead during rock breaking does not cause it to rotate. If the test soil is soft soil simulating soft soil strata, and the stratum itself has cohesive properties, due to the initial consolidation of the soft soil, the end face of the soft soil away from the propulsion piston 4 has a certain degree of self-stability. Therefore, after the soil hopper 3 is flipped to a horizontal position, there is no need to consider the instability of the soft soil. For strata that do not have cohesive properties or do not have self-stability after initial consolidation, ... After applying load to establish initial confining pressure and then unloading, add a layer of cohesive soil or apply a layer of adhesive to the end face of the soft soil away from the propulsion piston 4 to make it self-stabilizing after reversal and prevent the soft soil from falling out of the soil hopper 3. During the test, the cutterhead needs to cut off the cohesive soil or the part coated with adhesive before data acquisition. If the test soil is soft soil and rock blocks simulating a composite stratum, the same treatment method as for the soft soil part is adopted according to whether the soft soil has self-stabilization after the load is applied. That is to say, for those with self-stabilization, no additional treatment is required before reversal, and for those without self-stabilization, add a layer of cohesive soil or apply a layer of adhesive.

[0079] In addition, it should be noted that if the simulated strata are hard rock or soft soil, since the test soil is evenly distributed in the soil silo 3, the load can be applied by the hydraulic cylinder with pressure plate to achieve a realistic simulation of the confining pressure of the stratum environment. For composite strata, due to the limitation of hard rock, the soft soil part is difficult to achieve the confining pressure of the real stratum environment, and additional pressure needs to be applied to the soft soil part. Therefore, when simulating composite strata, the anti-roll part 7 of the upper part of the propulsion piston 4 needs to be replaced with an air bladder, and air or liquid needs to be injected into the air bladder to make the confining pressure of the entire test soil consistent with the confining pressure of the simulated stratum depth, while ensuring that the soft soil and rock blocks can be pushed synchronously by the propulsion piston 4.

[0080] 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. An anti-torsion propulsion piston device, characterized in that, include: Reaction support frame (2); The soil silo (3) is fixed on the reaction support frame (2), and the soil silo (3) is configured as a cylindrical structure with openings at both ends in the axial direction; The loading mechanism includes a thrust piston (4) and a first drive member (5). The thrust piston (4) is located inside the soil silo (3) and is in a sealed sliding fit with the soil silo (3). The first drive member (5) is mounted on the reaction support frame (2) and can drive the thrust piston (4) to reciprocate along the axial direction of the soil silo (3). The anti-rotation mechanism includes an anti-torsion guide column (6) and an anti-rolling part (7). The anti-torsion guide column (6) is eccentrically disposed on the propulsion piston (4) and slides in cooperation with the reaction support frame (2). The anti-rolling part (7) is disposed at one end of the propulsion piston (4) facing away from the reaction support frame (2) and can be inserted into the soil to limit and fix the soil.

2. The anti-torsion propulsion piston device according to claim 1, characterized in that, The anti-rolling part (7) is configured as a strip-shaped protrusion, and a corresponding groove is provided on the soil.

3. The anti-torsion propulsion piston device according to claim 2, characterized in that, The anti-roll part is detachably connected to the propulsion piston (4), and an airbag is detachably connected to one end face of the propulsion piston (4) on which the anti-roll part (7) is located.

4. The anti-torsion propulsion piston device according to claim 3, characterized in that, It also includes a base (1), which includes a fixed skid frame (11) and a movable skid frame (12). The reaction support frame (2) is disposed on the movable skid frame (12), and the movable skid frame (12) is slidably disposed on the fixed skid frame (11).

5. The anti-torsion propulsion piston device according to claim 4, characterized in that, The reaction support frame (2) is rotatably connected to the movable skid frame (12).

6. The anti-torsion propulsion piston device according to any one of claims 1-5, characterized in that, The first driving member (5) is provided in multiple forms and its output ends are evenly distributed on the propulsion piston (4).

7. The anti-torsion propulsion piston device according to any one of claims 1-5, characterized in that, The soil silo (3) is detachably connected to the reaction support frame (2).

8. The anti-torsion propulsion piston device according to any one of claims 1-5, characterized in that, The thrust piston (4) is provided with an annular accommodating groove in the circumferential direction to accommodate a lip seal ring, and the accommodating groove is connected to an oil injection port.

9. The anti-torsion propulsion piston device according to claim 8, characterized in that, The end of the propulsion piston (4) facing away from the reaction support frame (2) is also connected to an annular elastic sealing ring, which is always in contact with the soil hopper (3).

10. A method for using the anti-torsion propulsion piston device, comprising using the anti-torsion propulsion piston device as described in claim 5 in conjunction with a simulated tunnel boring machine to simulate tunnel boring machine construction under different geological conditions, wherein the simulated tunnel boring machine includes a cutterhead that is rotatably and sealed to the soil hopper (3), characterized in that, The usage method includes the following steps: Prepare test soil according to the strata to be simulated. The simulated strata include one of hard rock strata, soft soil strata, and composite strata. Adjust the position and angle of the soil silo (3) so that the end away from the reaction support frame (2) is open upwards. After filling the soil silo (3) with the test soil, apply a load to the test soil according to the simulated geological environment to establish preliminary confining pressure, and then unload. The soil hopper (3) is reversed and moved to connect with the cutter head, the opening of the soil hopper (3) is closed, and the propulsion piston (4) is pushed to make the cutter head rotate.

11. The method of using the anti-torsion propulsion piston device according to claim 10, characterized in that, When the test soil being filled is a rock block simulating a hard rock stratum, the rock block is first processed into a cylindrical geometric shape consistent with the radial cross section of the soil silo (3), and then grooved so that it can be inserted and matched with the anti-roll part (7); when the test soil being filled is soft soil simulating a soft soil stratum and the soft soil does not have self-stability, after applying a load to establish preliminary confining pressure and unloading, a layer of cohesive soil or a layer of adhesive is added to the end face of the soft soil away from the propulsion piston (4); when the test soil being filled is soft soil and rock block simulating a composite stratum and the soft soil does not have self-stability, after applying a load to establish preliminary confining pressure and unloading, a layer of cohesive soil or a layer of adhesive is added to the end face of the soft soil away from the propulsion piston (4).

12. The method of using the anti-torsion propulsion piston device according to claim 11, characterized in that, When the test soil being filled is soft soil and rock blocks simulating a composite stratum, the anti-roll part (7) of the upper half of the propulsion piston (4) is replaced with an air bladder, and air or liquid is injected into the air bladder to ensure that the soft soil and rock blocks can be pushed synchronously by the propulsion piston (4).

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