Experimental device for curve shield tunneling stratum deformation research and construction method

Abstract

The invention belongs to the field of shield tunnels, and discloses an experimental device for curve shield tunneling stratum deformation research and a construction method, a model test box is used for containing a soil body to simulate an underground soil layer, a shield model assembly capable of performing curve tunneling along a guide rail device is combined, and the actual curve shield construction working condition is reproduced. Through cooperation of the track system with the adjustable curve radius and the plugging device, variable-curvature tunneling of the shield model in a closed soil body is achieved, and the monitoring device is used for capturing horizontal deformation data of the soil body in real time. The plugging device dynamically adapts to the curvature change of the track to ensure the soil boundary sealing performance. According to the device, a quantifiable research platform for the curve tunneling-soil body response coupling effect is constructed for the first time, the mapping relation between the curve radius and the stratum deformation rule can be systematically revealed, the influence mechanism of factors such as over-excavation and uneven construction loads on stratum loss is defined, a theoretical basis is provided for predicting ground surface settlement and controlling horizontal displacement, and the method is suitable for large-scale popularization and application. And the technical blank that the curve shield is lack of experimental verification is effectively filled.

Description

Technical Field

[0001] This invention belongs to the field of shield tunnel technology, specifically relating to an experimental device and construction method for studying ground deformation during curved shield tunneling. Background Technology

[0002] With the large-scale construction of urban subways, the urban subway network is becoming increasingly dense. The construction environment for newly built tunnels is extremely complex, necessitating the use of curved routes to avoid important underground structures, leading to a surge in curved shield tunnel projects. The construction of urban subways primarily employs the shield tunneling method. Compared to traditional tunnel construction methods, the shield tunneling method has advantages such as less impact on surface traffic and the surrounding environment, high mechanization, fast construction speed, safety, environmental friendliness, and immunity to weather conditions.

[0003] However, shield tunneling is a complex and difficult-to-control process. Due to constraints such as the surrounding environment, construction technology, and complex geological conditions, it is impossible to completely avoid surface settlement and horizontal displacement caused by ground movement during subway shield tunneling. When surface settlement and horizontal displacement exceed certain limits, they will affect the normal use of surface buildings, impact their safety, and even cause serious building collapses. Excessive horizontal displacement has a significant impact on existing pressure pipelines in the soil, especially vulnerable ones such as gas pipes, heating pipes, and water supply pipes. Once damaged, the consequences would be unimaginable. Because the tunnel is curved, the shield tunneling machine needs to over-excavate the soil to achieve turning, causing soil voids on the inside of the curve, increased ground loss, and uneven construction loads. These factors make the excavation face more unstable and even cause surface collapse. Uneven disturbance to the soil on both sides of the tunnel can easily lead to excessive ground deformation and tunnel structural heave, which are extremely difficult to control and further increase construction risks. Meanwhile, due to a lack of experimental verification, the patterns of surface settlement and horizontal deformation of strata caused by curved shield tunnel excavation remain unclear.

[0004] Therefore, due to the lack of experimental verification, the laws governing surface settlement and horizontal deformation of strata caused by curved shield tunnel excavation are still unclear, and cannot provide guidance and reference for actual curved shield tunnel construction. Summary of the Invention

[0005] This invention provides an experimental device and construction method for studying soil deformation during curved shield tunneling. Using this experimental device, surface settlement data and horizontal displacement data of the soil monitored during the experiment can be obtained. Then, by drawing deformation displacement diagrams, the deformation pattern of the soil can be determined, providing guidance and reference for actual curved shield tunnel construction.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: An experimental apparatus for studying ground deformation during curved shield tunneling includes: Model test chamber, used to hold soil to simulate underground soil layers; The shield tunneling model component is used to simulate the actual shield tunneling process by passing through a model test box in a tunneling manner. The guide rail device, in conjunction with the track, provides tunneling routes with different curve radii for the shield model assembly to achieve curved shield tunneling; the track is laid at the inlet, outlet and bottom of the model test box; The sealing devices are respectively installed at the inlet and outlet of the model test box. They are used to seal the inlet and outlet of the model test box during the backfilling process and to cooperate with the track during the experiment so that the shield model components can adapt to the tunneling route with different curve radii. The monitoring device is used to collect data on horizontal soil deformation and soil settlement caused by the excavation of the shield tunneling model components during the experiment.

[0007] Furthermore, the model test chamber includes a chamber body with an open top and steel plates on all sides; one side of the chamber body has an openable side plate for removing soil from the model test chamber after the experiment; multiple horizontal monitoring holes are provided along the left and right symmetrical axes of the front and rear sides of the chamber body for inserting monitoring devices; openings are provided on the left and right sides of the chamber body as the inlet and outlet of the model test chamber, and the inlet and outlet are sealed and opened by a sealing device.

[0008] Furthermore, the monitoring device includes a horizontal measuring probe and a settlement measuring probe; the horizontal measuring probe is inserted into the horizontal monitoring hole and is used to collect horizontal deformation data of the soil during the tunneling of the shield model assembly; a monitoring steel frame is installed on the top of the model test box; the monitoring steel frame includes multiple rows of square steel frames; multiple settlement monitoring holes are opened on the square steel frames; the settlement measuring probe is inserted into the settlement monitoring hole until it contacts the soil surface and is used to collect settlement data of the soil during the tunneling of the shield model assembly.

[0009] Furthermore, the sealing device includes a double-layered slide rail groove, which is welded to the inlet and outlet of the model test box. A first sealing steel plate is movably connected to the outer slide rail groove, and a second sealing steel plate is movably connected to the inner slide rail groove. The second sealing steel plate has an n-shaped hole for the passage of the shield tunneling model assembly. By blocking the n-shaped hole on the second sealing steel plate with the first sealing steel plate, the inlet and outlet of the model test box are sealed. By horizontally pushing and pulling the first and second sealing steel plates, the n-shaped hole guides and restricts the shield tunneling model assembly, allowing the shield tunneling model assembly to adapt to tunneling routes with different curve radii.

[0010] Furthermore, the shield model assembly includes a shield model machine and shield segments; the shield segments are spliced ​​to the tail of the shield model machine after each ring of tunneling is completed, so as to simulate the actual tunneling conditions; the shield model machine includes a shield shell; the bottom of the shield shell has multiple grooves; the guide rail device is set in the grooves.

[0011] Furthermore, the guide rail device includes a hub connected within the groove; the hub includes a wheel, a bearing, and a cross shaft; One end of the horizontal shaft is welded to the groove of the shield shell, and the other end is welded to the center of the bearing; the bearing is welded to the wheel; the wheel is slidably mounted on the track.

[0012] Furthermore, the experimental apparatus also includes a support assembly; the support assembly includes a platform respectively disposed at the inlet and outlet of the model test chamber; sleepers are fixed on the platform, and rails are installed on the sleepers; the platform located at the inlet of the model test chamber is connected to a starting reaction frame.

[0013] A construction method for an experimental device for studying ground deformation during curved shield tunneling, based on the aforementioned experimental device for studying ground deformation during curved shield tunneling, comprising: After sealing the model test chamber with a sealing device, the model test chamber is filled with soil. Under the action of the guide rail device, the shield model assembly is controlled to tunnel along the track, enter the model test box through the sealing device at the inlet, and then drive out of the model test box through the sealing device at the outlet; among them, by adjusting the sealing device, the shield model assembly can adapt to the tunneling route with different curve radii; During the tunneling process of the shield model component, monitoring devices are used to collect data on the horizontal deformation and settlement of the soil caused by the tunneling of the shield model component.

[0014] Furthermore, during the tunneling process of the shield model assembly, the horizontal deformation data and settlement data of the soil are recorded once for each ring of tunneling. At the same time, a ring of segments is assembled at the tail of the shield model assembly and grouting is performed until the shield model assembly drives out of the model test box.

[0015] Furthermore, after collecting data on horizontal soil deformation and soil settlement caused by the tunneling of the shield model components through the monitoring device, the process includes: Based on the collected data on horizontal soil deformation and settlement, a soil deformation graph is drawn to determine the surface settlement and horizontal displacement patterns caused by curved shield tunnel excavation.

[0016] Compared with the prior art, the present invention has the following beneficial effects: This invention provides an experimental device for studying ground deformation during curved shield tunneling. A model test chamber holds soil to simulate underground soil layers, and a shield model component capable of curved tunneling along a guide rail replicates actual curved shield tunneling construction conditions. This device, through the coordinated operation of an adjustable curve radius track system and a sealing device, enables the shield model to tunnel at varying curvature within enclosed soil, while simultaneously using a monitoring device to capture real-time data on horizontal soil deformation. The sealing device dynamically adapts to changes in track curvature to ensure the sealing of the soil boundary. This design, through physical model experiments, is the first to construct a quantifiable research platform for the coupling effect of curved tunneling and soil response. It can systematically reveal the mapping relationship between curve radius and ground deformation patterns, clarify the influence mechanism of factors such as over-excavation and uneven construction loads on ground loss, and provide a theoretical basis for predicting surface settlement and controlling horizontal displacement in practical engineering, effectively filling the technical gap of lacking experimental verification for curved shield tunneling.

[0017] Preferably, in this invention, the model test chamber adopts a box structure with an open top and steel plates on all four sides, and is equipped with openable and closable side panels and horizontal monitoring holes. This ensures both the convenience of backfilling and observation, and the rigidity of the box. The symmetrically arranged horizontal monitoring holes facilitate the collection of horizontal displacement data of the soil at multiple points, and the detachable side panel design greatly improves the efficiency of soil cleaning after the experiment. This structural design significantly improves the operability and reusability of the device while ensuring experimental accuracy.

[0018] Preferably, in this invention, the monitoring system achieves three-dimensional acquisition of soil horizontal deformation data through a combination of horizontal and settlement measuring probes. The horizontal measuring probes pass through the monitoring holes in the box and directly contact the soil, while the settlement measuring probes measure surface settlement through monitoring holes on the top steel frame. This dual-dimensional monitoring method can simultaneously capture the three-dimensional deformation characteristics of the soil during tunneling, providing complete data support for analyzing the asymmetric stratum response caused by curved tunneling.

[0019] Preferably, in this invention, the sealing device adopts a combination structure of double-layer sliding rail groove and movable steel plate, and achieves both dynamic sealing and guiding functions through the unique design of the n-shaped holes. The first sealing steel plate ensures the sealing during the backfilling stage, while the adjustable holes of the second sealing steel plate guide the shield model to enter and exit according to the set curvature. This structure solves the technical problem of balancing boundary sealing and trajectory control in curved tunneling experiments, ensuring a high degree of consistency between experimental conditions and actual engineering.

[0020] Preferably, in this invention, the shield tunneling model component accurately simulates the actual shield tunneling construction process through the coordinated operation of the segment assembly system and the guide rail device. The real-time assembly of the tail segments reproduces the formation process of the tunnel structure, and the guide rail system with the bottom groove ensures the accuracy of the tunneling trajectory. This design enables the model experiment to truly reflect the dynamic process of the interaction between the shield tunneling and the strata, providing a reliable platform for studying the impact of construction parameters on strata disturbance.

[0021] Preferably, in this invention, the guide rail device employs a hub bearing system that precisely matches the track. Propulsion force is transmitted through a transverse shaft welded to the shield shell, and the bearing-supported wheels run smoothly along the track. This low-friction transmission structure ensures precise trajectory control during curved tunneling and effectively simulates the propulsion mechanics characteristics of an actual tunnel boring machine, creating ideal experimental conditions for studying the relationship between tunneling resistance and ground deformation under different curvatures.

[0022] Preferably, in this invention, the track system forms a continuous guiding path inside and outside the box-shaped structure through sleepers and fasteners, and the setup of the inlet platform and the launching reaction frame replicates the mechanical boundary conditions in actual construction. This full-path track support system ensures stable tunneling of the shield model from launch to reception, providing a standardized experimental environment for studying the ground abrupt response at the junction of curved and straight sections.

[0023] This invention provides a construction method for an experimental device used in studying ground deformation during curved shield tunneling. Based on this experimental device, the method constructs a ground environment by sealing the model box with a sealing device and backfilling it with soil. Guided by a guide rail device, the shield model is controlled to tunnel along a preset curved track, and a monitoring system collects real-time data on horizontal soil deformation. The sealing device can dynamically adjust to different curve radii to ensure the sealing of the soil boundary during the shield model's entry and exit. The guide rail device precisely controls the variable curvature trajectory of the shield model, replicating actual over-excavation and uneven load conditions. The monitoring device simultaneously captures the three-dimensional soil response throughout the entire tunneling process. This method achieves, for the first time, a physical simulation of the entire construction cycle of curved shield tunneling. Through controllable experimental conditions, it quantitatively reveals the mapping law between the curve radius and ground deformation, clarifies the influence mechanism of factors such as over-excavation voids and uneven disturbance on surface settlement and horizontal displacement, and provides a scientific basis for predicting deformation trends and optimizing construction parameters in actual engineering. It effectively solves the technical problem of lacking experimental verification for curved shield tunneling. Attached Figure Description

[0024] Figure 1 A schematic diagram of the structure of an experimental device for studying ground deformation during curved shield tunneling, provided in an embodiment of the present invention; Figure 2 A top view of an experimental apparatus for studying ground deformation during curved shield tunneling, provided in an embodiment of the present invention; Figure 3 This is a top view of the model experimental box provided in an embodiment of the present invention; Figure 4 The diagram shows the structure of the guide rail device provided in an embodiment of the present invention, wherein the left figure is the overall guide rail device and the right figure is a partial schematic diagram. Figure 5 This is a schematic diagram of the disassembled structure of the monitoring device provided in an embodiment of the present invention; Figure 6 A schematic diagram of the disassembled structure of a wheel hub provided in an embodiment of the present invention; Figure 7 This is a bottom view of the shield tunneling model machine provided in an embodiment of the present invention; Figure 8 A schematic diagram showing the disassembled structure of the inlet and outlet sealing device for the model experimental box provided in an embodiment of the present invention.

[0025] Figure label: 1. Settlement measuring probe; 2. Model test box; 3. Sealing device; 4. Computer; 5. Starting reaction frame; 6. Sleeper; 7. Platform; 8. Shield tunnel model machine; 9. Hinge; 10. Horizontal measuring probe; 11. Side plate; 12. Guardrail buckle; 13. Square tube steel; 14. Monitoring steel frame; 15. Track; 16. Shield tunnel segment; 17. Opening; 18. Horizontal monitoring hole; 19. Cylindrical block; 20. Bolt hole; 21. Buckle bolt; 22. Plate buckle; 23. Settlement monitoring hole; 24. Wheel; 25. Bearing; 26. Horizontal shaft; 27. Wheel hub; 28. Shield shell; 29. ​​Slide rail groove; 30. Pulley; 31. First sealing steel plate; 32. Second sealing steel plate; 33. Handle. Detailed Implementation

[0026] To further understand the content of this invention, the invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments are merely illustrative and not limiting of the invention.

[0027] As described in the background section, the shield tunneling process is complex and difficult to control. Influenced by environmental, technological, and geological factors, construction can lead to surface settlement and horizontal displacement, threatening the safety of surface buildings and underground pipelines. Curved shield tunnels, due to over-excavation and uneven loading, are even more prone to problems such as unstable excavation faces and excessive ground deformation, further increasing construction risks. Currently, due to a lack of experimental verification, the laws governing surface settlement and horizontal deformation caused by curved shield tunnel excavation are not yet clear. There is an urgent need to conduct in-depth research on the mechanisms of soil surface settlement and horizontal displacement through model tests.

[0028] To address the aforementioned issues, this embodiment provides an experimental device for studying ground deformation during curved shield tunneling. This device is easy to operate and implement, and can obtain surface settlement and horizontal displacement data of the soil monitored during the experiment. By plotting deformation-displacement diagrams, the deformation patterns of the soil can be determined, providing guidance and reference for actual curved shield tunnel construction.

[0029] This embodiment provides an experimental device for studying ground deformation during curved shield tunneling, comprising: a model test chamber 2 for holding soil to simulate underground soil layers; a shield model assembly for tunneling through the model test chamber 2 to simulate the actual shield machine construction process; a guide rail device, which cooperates with a track 15 to provide the shield model assembly with tunneling routes of different curve radii to achieve curved shield tunneling; the track 15 is arranged at the inlet, outlet, and bottom of the model test chamber 2; a sealing device 3, which is respectively set at the inlet and outlet of the model test chamber 2, for sealing the inlet and outlet of the model test chamber 2 during the backfilling process and for cooperating with the track 15 during the experiment to enable the shield model assembly to adapt to tunneling routes of different curve radii; and a monitoring device for collecting data on horizontal soil deformation and soil settlement caused by the tunneling of the shield model assembly during the experiment.

[0030] The experimental apparatus for studying ground deformation during curved shield tunneling provided in this embodiment will be described in detail below with reference to the accompanying drawings: like Figure 1-8 As shown, this embodiment relates to an experimental apparatus and construction method for studying ground deformation caused by curved shield tunneling. It mainly includes a model test box 2 simulating ground conditions, a shield tunneling model machine 8, shield segments 16, a launching reaction frame 5, a sealing device 3, a track 15, a support platform 7, and a monitoring steel frame 14. The shield tunneling model machine 8 is placed on the track 15 at the launching point to simulate the curved shield tunneling process. The experimental method includes the following steps: like Figure 1 , Figure 2 , Figure 3 and Figure 8As shown, in this embodiment, the model test box 2 is a rectangular box made of high-strength steel plate. The upper surface of the box is uncovered, while the rear and bottom surfaces are made of complete steel plates. A rectangular opening is opened in the lower middle part of the front side, which is sealed with a side plate 11 of the same size as the opening. The lower part of the side plate 11 is connected to the lower part of the box by four hinges 9, and the hinges 9 are fixed to the box by bolts. The upper part of the side plate 11 is connected to the box by four side panels 12. When the side panels 12 are opened, the side plate can be vertically rotated 90 degrees to keep it in contact with the ground. Thirteen small circular horizontal monitoring holes 18 are opened along the left and right symmetrical axes of the front and rear sides. Horizontal measuring rods 10 are inserted into the horizontal monitoring holes 18 to measure the horizontal deformation data of the soil during shield tunnel excavation. The front side is reinforced with square steel tubes 13 on the upper part of the side plates 11. The square steel tubes 13 used to reinforce the rear side are the same as those on the front side, and they are arranged all over the entire side. An opening 17 is provided on each of the left and right sides, serving as the launching opening and the receiving opening respectively, facilitating the tunnel boring machine 8 to excavate from the launching opening and exit from the receiving opening. The box body is reinforced with square steel tubing 13. On the left and right sides, to avoid obstructing the horizontal pushing and pulling requirements of the inlet and outlet sealing devices 3, no reinforcement is applied within the area of ​​the inlet and outlet sealing devices 3. Figure 8 As shown, the sealing device 3 for the starting opening and the receiving opening is the same, consisting of a first sealing steel plate 31 and a second sealing steel plate 32. The second sealing steel plate 32 is longer than the first sealing steel plate 31. The overall size of the sealing device 3 is larger than the opening 17. An "n"-shaped hole is formed in the middle of the first sealing steel plate 31 and the second sealing steel plate 32. The sliding component of the sealing device 3 consists of a slide rail groove 29 and a pulley 30. When installed, the upper and lower slide rail grooves 29 are positioned opposite each other, and their sides are fixed to the steel plate of the housing by welding. The second sealing steel plate 32 is placed on the inner slide rail groove 29 via two pulleys 30 on each side, while the first sealing steel plate 31 is placed on the outer slide rail groove 29. Lubricating oil is applied to the pulleys 30 during installation. Handles 33 are welded to both the first and second sealing steel plates 31 and 32 to facilitate horizontal pushing and pulling of the plates. By pushing and pulling left and right, the opening can be sealed, and the plates can be adapted to tunneling on curves with different radii. Experiments can be conducted to change the radius of curved shield tunnels, exploring the impact of radius changes on ground deformation. Figure 3 As shown, four cylindrical blocks 19 are welded to the four corners of the top of the model test chamber 2 for placing monitoring devices. The soil inside the chamber is filled in layers, with each layer being 30cm thick. Figure 4As shown, when filling the soil to the starting and receiving openings of the model test box 2, the track 15 within the box area is laid. There are four sleepers 6 within the box area, one on each side at a distance of 17 from the box opening, and one sleeper 6 at each of the one-third and two-thirds positions of the box. The track 15 and sleepers 6 are connected to form a whole by fastening plates 22 and fastening bolts 21. Then, the sealing devices 3 at the entrances and exits on both sides are sealed, and the filling continues. When the soil is filled to the horizontal monitoring hole 18, a horizontal measuring probe 10 is installed in the horizontal monitoring hole 18. The horizontal displacement deformation value of the soil below the track 15 is not collected; only the horizontal displacement value from the track 15 to the surface of the box is detected. The horizontal measuring probe 10 passes through the hole in the side plate 11 at a horizontal distance of 0.5m from the track in the soil. The filling continues until the box is full. The monitoring device is installed on the box to prepare for monitoring soil deformation data.

[0031] like Figure 1 and Figure 5 As shown, the monitoring device consists of a monitoring steel frame 14 made of welded steel bars and a settlement measuring probe 1. The monitoring steel frame 14 is shaped like a table, with multiple rows of square steel frames on its upper surface. Circular settlement monitoring holes 23 are opened on the steel frames, allowing the settlement measuring probe 1 to be inserted. The bottom of the four legs has cylindrical grooves that fit into the cylindrical blocks 19 at the four corners of the housing, forming a stable whole and providing stable support for the settlement measuring probe 1. Figure 5 As shown, the settlement measuring probe 1 is inserted into the settlement monitoring hole 23 on the monitoring steel frame 14 until it contacts the soil surface. The settlement measuring probe 1 is made of round steel bars and may have scales on it for easy reading. After all the surface settlement and horizontal displacement measuring probes are placed, the initial reading of the measuring probe is read. The value of the surface settlement measuring probe 1 is based on the reading on the upper surface of the monitoring steel frame 14, and the horizontal displacement is based on the value on the outer surface of the box steel plate.

[0032] like Figure 1 , Figure 2 As shown, the support device consists of a steel frame, steel plates, and rails 15. Multiple square steel tubes 13 are welded together to form a support platform 7, and steel plates are welded to the top surface to form the support platform 7. Figure 4 As shown, the track 15 is connected to the sleeper 6 via the fastening plate 22 and fastening plate bolt 21, and placed on the support frame 7. The support frames 7 at the starting point and the receiving point are the same. The track 15 and the support frame 7 in the starting range and the receiving range are installed. The starting reaction frame 5 is close to the back of the support frame 7 at the starting point. The starting reaction frame 5 is welded from steel plate and square steel pipe 13.

[0033] like Figure 1 , Figure 6 and Figure 7As shown, four oblique cylindrical grooves are set at the lower part of the shield shell 28 of the shield model machine 8 for welding hubs 27. The hub 27 consists of wheels 24, bearings 25, and a horizontal shaft 26. One end of the horizontal shaft 26 is welded to the center of the bearing 25, and the other end is welded to the shield shell 28. The bearing 25 is welded onto the wheel 24 to form the hub 27. Its main function is to move forward along the curved track and constrain the tunneling route of the shield machine. In the actual construction of curved shield tunnels, controlling the tunneling axis is a technical challenge, and it is difficult to achieve tunneling along a curve. Lubricating oil is applied to the bearings 25 to reduce friction. The shield model machine 8 is placed on the launching platform 7, and the shield tail is placed on the launching reaction frame 5. The sealing door of the sealing device 3 at the launching point is opened, and the computer 4 controls the tunneling of the shield machine. Data is recorded once after each segment is tunneled. At the shield tail, a ring of segments is assembled and grouted. When the tunneling is nearing the receiving point, the sealing door of the sealing device 3 at the receiving point is opened, and the shield machine model 8 is placed on the receiving platform to complete the curved shield tunneling simulation experiment. The side plate 11 of the model test box 2 is opened, and the soil inside the box is removed. Finally, based on the experimental data, a graph of soil deformation is plotted to obtain the surface settlement and horizontal displacement patterns caused by the curved shield tunneling.

[0034] In summary, this invention provides an experimental device for studying ground deformation during curved shield tunneling, which has the following advantages compared to existing technologies: This invention improves the shield tunneling model machine, enabling it to advance along a curved track. The use of a track and guide rail system solves the technical challenge of correcting the shield machine's deviation. By placing measuring probes on the front and rear sides of the model test chamber to measure horizontal displacement, and by adding a steel frame to the top of the chamber to fix the measuring probes for measuring surface settlement, the data acquisition method is optimized, ensuring the data is accurate and reliable. To facilitate soil unloading after the experiment, side plates are added to the model test chamber, reducing labor costs. This device effectively replicates the steps and engineering conditions of actual construction, thus obtaining accurate data on surface settlement and horizontal displacement caused by curved shield tunnel construction. The model test chamber can accommodate curved shield tunneling tests with different curve radii, allowing for the study of the impact of radius changes on ground deformation. By obtaining surface settlement and horizontal displacement data of the soil monitored during the experiment, and plotting soil deformation and displacement diagrams, the deformation patterns of the soil are revealed, providing guidance and reference for actual curved shield tunnel construction.

[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. An experimental apparatus for studying ground deformation during curved shield tunneling, characterized in that, include: Model test chamber (2) is used to hold soil to simulate underground soil layers; A shield tunneling model assembly is used to simulate the actual shield tunneling process by passing through a model test box (2) in a tunneling manner; The guide rail device, in conjunction with the track (15), provides tunneling routes with different curve radii for the shield model assembly to achieve curved shield tunneling; the track (15) is laid at the inlet, outlet and bottom of the model test box (2); The sealing device (3) is set at the inlet and outlet of the model test box (2) respectively. It is used to seal the inlet and outlet of the model test box (2) during the filling process and to cooperate with the track (15) during the experiment so that the shield model assembly can adapt to the tunneling route with different curve radii. The monitoring device is used to collect data on horizontal soil deformation and soil settlement caused by the excavation of the shield tunneling model components during the experiment.

2. The experimental apparatus for studying ground deformation during curved shield tunneling according to claim 1, characterized in that, The model test chamber (2) includes a box body with an open top and steel plates on all sides. One side of the box body is provided with an openable side plate (11) for removing the soil from the model test chamber (2) after the experiment. Multiple horizontal monitoring holes (18) are provided along the left and right symmetrical axes of the front and rear sides of the box body for inserting the monitoring device. Openings (17) are provided on the left and right sides of the box body to serve as the inlet and outlet of the model test chamber (2). The sealing and opening of the inlet and outlet are achieved by the sealing device (3).

3. The experimental apparatus for studying ground deformation during curved shield tunneling according to claim 2, characterized in that, The monitoring device includes a horizontal measuring probe (10) and a settlement measuring probe (1); the horizontal measuring probe (10) is inserted into the horizontal monitoring hole (18) and is used to collect horizontal deformation data of the soil during the tunneling of the shield model assembly; a monitoring steel frame (14) is installed on the top of the model test box (2); the monitoring steel frame (14) includes multiple rows of square steel frames; multiple settlement monitoring holes (23) are opened on the square steel frames; the settlement measuring probe (1) is inserted into the settlement monitoring hole (23) until it contacts the soil surface and is used to collect settlement data of the soil during the tunneling of the shield model assembly.

4. The experimental apparatus for studying ground deformation during curved shield tunneling according to claim 1, characterized in that, The sealing device (3) includes a double-layered slide rail groove (29), which is welded to the inlet and outlet of the model test box (2). The outer slide rail groove (29) is movably connected to a first sealing steel plate (31), and the inner slide rail groove (29) is movably connected to a second sealing steel plate (32). The second sealing steel plate (32) has an n-shaped hole for the shield model assembly to pass through. By blocking the n-shaped hole on the second sealing steel plate (32) with the first sealing steel plate (31), the inlet and outlet of the model test box (2) are sealed. By horizontally pushing and pulling the first sealing steel plate (31) and the second sealing steel plate (32), the n-shaped hole is used to guide and restrict the shield model assembly, so that the shield model assembly can adapt to the tunneling route with different curve radii.

5. The experimental apparatus for studying ground deformation during curved shield tunneling according to claim 1, characterized in that, The shield model assembly includes a shield model machine (8) and shield segments (16); the shield segments (16) are spliced ​​at the tail of the shield model machine (8) after each ring of tunneling is completed, so as to simulate the actual tunneling conditions; the shield model machine (8) includes a shield shell (28); the bottom of the shield shell (28) is provided with multiple grooves; the guide rail device is set in the grooves.

6. The experimental apparatus for studying ground deformation during curved shield tunneling according to claim 5, characterized in that, The guide rail device includes a hub (27) connected in the groove; the hub (27) includes a wheel (24), a bearing (25) and a cross shaft (26); One end of the horizontal shaft (26) is welded to the groove of the shield shell (28), and the other end is welded to the center of the bearing (25); the bearing (25) is welded to the wheel (24); the wheel (24) is slidably mounted on the track (15).

7. The experimental apparatus for studying ground deformation during curved shield tunneling according to claim 1, characterized in that, The experimental device also includes a support assembly; the support assembly includes a platform (7) respectively set at the inlet and outlet of the model test chamber (2); a sleeper (6) is fixed on the platform (7), and a track (15) is installed on the sleeper (6); the platform (7) located at the inlet of the model test chamber (2) is connected to an initiating reaction frame (5).

8. A construction method for an experimental apparatus for studying ground deformation during curved shield tunneling, based on the experimental apparatus for studying ground deformation during curved shield tunneling as described in any one of claims 1-7, characterized in that, include: After sealing the model test box (2) with the sealing device (3), fill the model test box (2) with soil; Under the action of the guide rail device, the shield model assembly is controlled to tunnel along the track (15), enter the model test box (2) through the sealing device (3) at the inlet, and then drive out of the model test box (2) through the sealing device (3) at the outlet; wherein, by adjusting the sealing device (3), the shield model assembly can adapt to tunneling routes with different curve radii; During the tunneling process of the shield model component, monitoring devices are used to collect data on the horizontal deformation and settlement of the soil caused by the tunneling of the shield model component.

9. The construction method of the experimental device for studying ground deformation during curved shield tunneling according to claim 8, characterized in that, During the tunneling process of the shield model component, the horizontal deformation data and settlement data of the soil are recorded once for each ring of tunneling. At the same time, a ring of segments is assembled at the tail of the shield model component and grouting is performed until the shield model component drives out of the model test box (2).

10. The construction method of the experimental device for studying ground deformation during curved shield tunneling according to claim 8, characterized in that, After collecting data on horizontal soil deformation and settlement caused by the tunnel boring machine (TBM) model component excavation through a monitoring device, the process includes: Based on the collected data on horizontal soil deformation and settlement, a soil deformation graph is drawn to determine the surface settlement and horizontal displacement patterns caused by curved shield tunnel excavation.

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