Reverse multi-attitude shield grouting simulation test device and test method

Abstract

The invention provides a reverse multi-attitude shield grouting simulation test device and a test method. The device comprises a model box and a shield tunnel model. The model box comprises a model box body, sealing covers and negative ring covers, the sealing covers and the negative ring covers are in one-to-one correspondence and can be replaced, and tunnel excavation under different shield gestures can be simulated respectively. The shield tunnel model comprises a shield shell and a tunnel lining, and the shield shell and the tunnel lining slide relatively through a sealing gum sponge cushion. The grouting holes are formed in the shield shell, the tunnel lining is pre-installed firstly, then the shield shell is reversely pulled out outwards, grouting is conducted at the same time, and the whole shield tail synchronous grouting process can be simulated. The tunnel lining comprises a plurality of rings of tunnel lining segments, each ring of tunnel lining segment comprises a plurality of concrete segments, and all the components are connected through mortise and tenon joint structures. On the premise that the shield attitude is adjustable, the simulation effect is good and the operation is simple, the complexity of similar test devices can be greatly reduced, and the defect that faults are easy to occur due to multi-element coupling is overcome.

Description

Technical Field

[0001] The invention relates to the technical field of synchronous grouting tests for shield tunnels, and in particular to a reverse multi-posture shield grouting simulation test device and a test method. Background Art

[0002] Shield tunneling technology is widely used in urban rail transit, railways, highways, water conservancy, and other sectors due to its exceptional safety, efficiency, applicability, and low environmental impact. Due to the excellent applicability of shield tunneling in urban areas, ground deformation and surface subsidence caused by shield construction have become key control indicators for shield tunneling, minimizing or avoiding adverse effects such as disturbance of existing urban buildings and structures.

[0003] Grouting technology during shield tunneling is crucial for ensuring surrounding rock stability, controlling ground deformation, and suppressing segment uplift. Appropriate grouting methods can promptly fill the gaps at the shield tail, and by adjusting the grouting pressure and mix ratio, soil disturbance can be minimized. However, due to the complexity and diversity of the ground, lack of visualization, and difficulty in monitoring during shield tunneling, the actual effects of grouting during engineering are currently difficult to assess.

[0004] Therefore, it is necessary to provide a shield tunnel grouting model with simple structure, convenient operation and accurate results. Summary of the Invention

[0005] The purpose of the present invention is to provide a reverse multi-posture shield grouting simulation test device and test method to solve the problems existing in the prior art.

[0006] The technical solution adopted to achieve the purpose of the present invention is as follows: a reverse multi-posture shield grouting simulation test device, including a model box and a shield tunnel model.

[0007] The model box includes a model box body, n sealing covers, and n negative ring covers. The model box body is a rectangular box with an open top. The four circumferential walls of the model box body are designated as the first side wall, the second side wall, the third side wall, and the fourth side wall, respectively. A through hole I is provided on the first side wall. Through hole I comprises n vertically overlapping circular holes. The n circular holes have different inclination angles. The n sealing covers have different hollowed-out portions formed on their covers. The sealing covers are affixed to the outer wall of the first side wall. The sealing covers cover through hole I, with the i-th sealing cover's hollowed-out portion exposing the i-th circular hole. A through hole II is provided on the third side wall. Through hole II is a circular hole. The negative ring cover comprises a cylindrical groove structure and a circular ring plate. The n negative ring covers have cylindrical groove structures with different inclination angles. The circular ring plate surrounds the cylindrical groove structure. The cylindrical groove structure is inserted into the inner cavity of the model box body through through hole II. The circular ring plate is affixed to the outer wall of the third side wall.

[0008] The shield tunnel model includes a shield shell model and a tunnel lining model. The shield shell model is a cylindrical structure. Pressure and displacement sensors are mounted on the outer wall of the shield shell model. The shield shell model is provided with a plurality of grouting holes. The grouting holes extend through both ends of the shield shell model's cylindrical wall. The plurality of grouting holes are evenly spaced circumferentially. The grouting holes extend parallel to the central axis of the shield shell model. The tunnel lining model is an overall cylindrical structure. Displacement sensors are mounted on the inner wall of the tunnel lining model. The tunnel lining model can be longitudinally split into a plurality of tunnel lining segments. The tunnel lining segments are an overall cylindrical structure. The tunnel lining segments can be circumferentially split into a plurality of concrete segments. The cross-sectional view of the concrete segments generally exhibits a fan-shaped ring structure. The shield shell model is mounted on the outer periphery of the tunnel lining model. The tunnel lining model and the shield shell model together constitute a simulated tunnel structure.

[0009] During operation, the model box is filled with soil. The simulated tunnel structure is embedded in the soil. The two ends of the simulated tunnel structure extend out of the model box, passing through a sealing cover or negative ring cover. The shield shell model is pulled out in the reverse direction at a constant speed to simulate shield tunnel excavation, while grouting is simultaneously injected into the grouting holes to simulate synchronous grouting. During the experiment, the corresponding sealing covers and negative ring covers were replaced to simulate shield tunnels with different slopes.

[0010] Furthermore, an embedding portion is provided on the side of the sealing cover facing the first side wall, and the embedding portion is embedded in the through hole II.

[0011] Furthermore, bolt holes are arranged on the model box body, the sealing cover and the negative ring cover. The sealing cover and the model box body, as well as the negative ring cover and the model box body are fixedly connected by bolts.

[0012] Furthermore, arc-shaped cylindrical grooves are provided at the joints of adjacent tunnel lining segments, and the arc-shaped cylindrical strips are simultaneously inserted into the corresponding arc-shaped cylindrical grooves of the adjacent tunnel lining segments.

[0013] Furthermore, annular grooves are spaced apart on the inner wall of the shield shell mold. Sealing adhesive sponge pads are affixed to these grooves. These sealing adhesive sponge pads ensure smoother sliding between the shield shell and the tunnel lining. The sponge pads' water-absorbing and swellable properties effectively prevent backflow of slurry from the shield tail.

[0014] Furthermore, the joints of the peripheral walls of the tunnel lining model are wrapped with waterproof tape.

[0015] The present invention also discloses a test method according to the above-mentioned reverse multi-posture shield grouting simulation test device, comprising the following steps:

[0016] S1: Select the negative ring cover that simulates the shield posture required for the test and fix it to the rear side of the model box with bolts.

[0017] S2: Assemble the concrete segments into tunnel lining segments, and then connect them longitudinally to form a section of tunnel lining. Then, put the shield shell on the outside of the assembled tunnel lining and pass through the front circular hole structure and the rear circular hole structure in turn, so that the tunnel lining rests on the bottom of the fixed negative ring cover. Then, select the corresponding sealing cover to seal the remaining gap in the front circular hole structure.

[0018] S3: Install pressure and displacement sensors on the outer wall of the shield shell, and install displacement sensors on the inner wall of the tunnel lining.

[0019] S4: Fill the model box with soil until it completely covers the shield tunnel, adjust the soil moisture content according to the test simulation requirements, and consolidate for a period of time.

[0020] S5: At the start of the test, while limiting the longitudinal displacement of the tunnel lining, the shield shell is slowly pulled out in the reverse direction using an automated device, and the pulled-out shield shell is supported by supports. An electric pump and a grouting pipe are used to synchronously inject grout into the shield tail through the grouting holes, parallel to the central axis of the tunnel. Each distance a segment is moved is considered a step, and several hours are waited after each step is completed.

[0021] S6: After the test is completed, the collected test data is imported into the computer for theoretical analysis.

[0022] The technical effect of the present invention is unquestionable: the shield tunnel grouting simulation device has a simple structure and is easy to operate. It can not only adjust the longitudinal posture of the shield tunnel through replaceable sealing covers and negative ring covers, but also adapt to different types of rock and soil. At the same time, the technical method of pulling out the shield shell in reverse not only utilizes reverse thinking, breaking the current rigid thinking of forward shield excavation in model tests, but also greatly reduces the complexity of the device. After the shield shell is pulled out in reverse, a shield tail gap is immediately formed, and the lining segments are exposed to the surrounding rock at the same time. And through the synchronous grouting of the shield tail, the actual engineering situation can be well simulated. In addition, each ring of the tunnel lining is composed of several concrete segments connected by a mortise and tenon structure, which well simulates the entire tunnel lining connected by arc-shaped cylindrical strips in actual engineering, so that its test deformation can be mapped to the bent bolts used in actual engineering, giving a reference for segment floating, deformation, and joint shear resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a cross-sectional view of the horizontal posture structure;

[0024] Figure 2 It is a cross-sectional view of the structure in an inclined posture;

[0025] Figure 3 for Figure 1 Schematic diagram of the structure of the middle model box;

[0026] Figure 4 for Figure 1 or Figure 2 The structural diagram of the sealing cover and negative ring cover adapted to different shield postures;

[0027] Figure 5 for Figure 1 or Figure 2 Schematic diagram of shield tunnel model structure in;

[0028] Figure 6 for Figure 5 Schematic diagram of shield shell structure;

[0029] Figure 7 for Figure 5 Schematic diagram of the tunnel lining segment structure.

[0030] In the figure: 1. Model box; 110. Model box body; 111. Circular hole structure; 112. Bolt hole; 120. Sealing cover; 121. Embedded part; 130. Negative ring cover; 131. Negative ring cover circular plate; 133. Uncovered hollow circular hole groove structure; 2. Shield tunnel model; 210. Shield shell; 211. Annular rectangular groove; 212. Grouting hole; 220. Tunnel lining; 221. Tunnel lining segment; 222. Concrete segment; 223. Arc-shaped cylindrical groove; 230. Sealing adhesive sponge pad. DETAILED DESCRIPTION

[0031] The present invention will be further described below with reference to the following examples, but it should not be understood that the scope of the present invention is limited to the following examples. Without departing from the above technical ideas of the present invention, various substitutions and modifications can be made according to common technical knowledge and customary means in the art, and all should be included in the scope of protection of the present invention.

[0032] Example 1:

[0033] This embodiment provides a reverse multi-posture shield grouting simulation test device, which includes a model box 1 and a shield tunnel model 2.

[0034] The model box 1 includes a model box body 110, n sealing covers 120, and n negative ring covers 130. The model box body 110 is a rectangular box with an open top. The four side walls of the model box body 110 are designated as the first side wall, the second side wall, the third side wall, and the fourth side wall. The first side wall is provided with a through hole I 111. The through holes I 111 comprise n vertically overlapping circular holes. The n circular holes have different inclination angles. The n sealing covers 120 have different hollowed-out portions formed on their covers. The sealing covers 120 are attached to the outer wall of the first side wall. The sealing covers 120 cover the through holes I 111, with the i-th circular hole exposed through the hollowed-out portion of the i-th sealing cover 120. The third side wall is provided with a through hole II 1110. The through hole II 1110 is a circular hole. The negative ring cover 130 comprises a cylindrical groove structure 133 and a circular ring plate 131. The n negative ring covers 130 have cylindrical groove structures 133 with different inclination angles. The annular plate 131 surrounds the cylindrical groove structure 133. The cylindrical groove structure 133 is inserted into the inner cavity of the mold box body 110 through the through hole II 1110. The annular plate 131 is attached to the outer wall of the third side wall.

[0035] The shield tunnel model 2 includes a shield shell model 210 and a tunnel lining model 220. The shield shell model 210 is cylindrical. Pressure and displacement sensors are mounted on the outer wall of the shield shell model 210. The shield shell model 210 is provided with a plurality of grouting holes 212. The grouting holes 212 extend through both ends of the shield shell model 210. The grouting holes 212 are evenly spaced along the circumference. The grouting holes 212 extend parallel to the central axis of the shield shell model 210. The tunnel lining model 220 is generally cylindrical. Displacement sensors are mounted on the inner wall of the tunnel lining model 220. The tunnel lining model 220 can be longitudinally split into a plurality of tunnel lining segments 221. The tunnel lining segments 221 are generally cylindrical. The tunnel lining segments 221 can be circumferentially split into a plurality of concrete segments 222. A cross-sectional view of the concrete segments 222 generally exhibits a fan-shaped ring structure. The shield shell model 210 is mounted on the outer periphery of the tunnel lining model 220. The tunnel lining model 220 and the shield shell model 210 together constitute a simulated tunnel structure.

[0036] During operation, the model box 1 is filled with soil. The simulated tunnel structure is embedded in the soil. The two ends of the simulated tunnel structure extend out of the model box, passing through the sealing cover 120 or the negative ring cover 130. The shield shell model 210 is pulled out in the reverse direction at a constant speed to simulate shield tunnel excavation, while grouting is simultaneously performed into the grouting holes 212 to simulate synchronous grouting. During the experiment, the corresponding sealing covers 120 and negative ring covers 130 were replaced to simulate shield tunnels with different slopes.

[0037] This example simulates the shield tunnel excavation process through a scaled physical model test. When the shield shell is pulled out in reverse, a gap is immediately formed at the shield tail, exposing the lining segments to the surrounding rock. Synchronous grouting at the shield tail effectively simulates actual engineering conditions. This allows for a clear understanding of the actual impact of shield grouting on the stratum and lining during shield tunnel excavation, further exploring theoretical mechanisms and providing valuable reference for practical engineering applications.

[0038] Example 2:

[0039] The main contents of this embodiment are the same as those of the first embodiment, wherein the sealing cover 120 is further provided with an embedding portion 121 on the side facing the first side wall. The embedding portion 121 is embedded in the through hole II 1110 .

[0040] Example 3:

[0041] The main contents of this embodiment are the same as those of embodiment 1, wherein bolt holes 112 are arranged on the mold box body 110, the sealing cover 120 and the negative ring cover 130. The sealing cover 120 and the mold box body 110, as well as the negative ring cover 130 and the mold box body 110 are fixedly connected by bolts.

[0042] Example 4:

[0043] The main contents of this embodiment are the same as those of embodiment 1, wherein arcuate cylindrical grooves 223 are provided at the joints of adjacent tunnel lining segments 221. The arcuate cylindrical strips are simultaneously inserted into the corresponding arcuate cylindrical grooves 223 of the adjacent tunnel lining segments 221.

[0044] Example 5:

[0045] This embodiment primarily shares the same features as Example 1, except that annular grooves 211 are spaced apart on the inner wall of the shield shell mold 210. Sealing adhesive sponge pads 230 are affixed to these grooves. These adhesive sponge pads 230 facilitate smoother sliding between the shield shell 210 and the tunnel lining 220. The sponge pads' water-absorbing and swellable properties effectively prevent backflow of slurry from the shield tail.

[0046] Example 6:

[0047] The main contents of this embodiment are the same as those of embodiment 1, wherein the joints of the peripheral wall of the tunnel lining 220 model are wrapped with waterproof tape.

[0048] Example 7:

[0049] The main contents of this embodiment are the same as those of embodiment 1, wherein reference Figures 1 to 3 The model box 1 includes a model box body 110 , a plurality of sealing covers 120 and a plurality of negative ring covers 130 . The shield tunnel model 2 includes a shield shell 210 , a tunnel lining 220 and a plurality of sealing adhesive sponge pads 230 .

[0050] The model box 1 is a rectangular trough structure without a cover. The space inside the box is 100 cm long (opening side), 75 cm wide (non-opening side), and 1 cm thick. The front side of the model box 1 is provided with three vertically continuous and partially overlapping circular hole structures 111. The circular hole structures 111 are opened at different inclination angles. The rear side of the model box is provided with a circular hole structure 111.

[0051] It is worth noting that in this embodiment, the circular hole structures 111 are opened at angles of +5°, ±0°, and -5°, respectively, to simulate horizontal shield tunneling and excavation at a steep ±5° slope. When constructing an actual physical model, different numbers and angles of holes can be selected to simulate various conditions in detail, depending on the simulation requirements of the experiment.

[0052] refer to Figure 4 The sealing cover 120 can fill the gap in the front of the model box, leaving only a circular hole structure 111. After the sealing cover 120 fills the gap, a sealing cover circular plate 121 of a certain thickness is extended outward to tightly fit the model box body 110. The sealing cover circular plate 121 is provided with bolt holes 122 around the circumference.

[0053] The negative ring cover 130 is capable of filling the entire gap at the rear of the model box. After filling the gap, the negative ring cover 130 still extends a circular plate 131 of a certain thickness to tightly fit the model box body 110. Bolt holes 133 are formed around the circumference of the negative ring cover circular plate 131. The rear half of the negative ring cover 130 is an uncovered hollow cylindrical groove structure 133. This uncovered hollow cylindrical groove structure 133 has different inclination angles, each of which is equal to the shield posture inclination angle.

[0054] The mold box 1 is provided with bolt holes 112 at positions corresponding to the sealing cover annular plate 121 and the negative ring cover annular plate 131. The mold box body is fixedly connected to the sealing cover 120 and the negative ring cover 130 by bolts.

[0055] refer to Figures 5 to 7 The shield shell 210 is a hollow cylindrical structure with a certain thickness. The inner wall of the shield shell 210 is provided with a continuous and uniform annular rectangular groove 211, and the shell is provided with a grouting hole 212. The annular rectangular groove is provided with a sealing sponge pad 230 with a backing of adhesive.

[0056] The space occupied by the grouting holes 212 is a slender cylinder, which is continuously and evenly arranged along the cross-sectional ring line of the shield shell 210 , and the axis thereof is parallel to the central axis of the shield shell 210 and passes through longitudinally.

[0057] The tunnel lining 220 is a long cylindrical structure. It includes a plurality of rings of tunnel lining segments 221 that can be longitudinally connected to form a long cylindrical structure. The tunnel lining segments 221 are short cylindrical structures. They include a plurality of concrete segments 222 that can be combined to form a short cylindrical structure.

[0058] The concrete segment 222 has a cross-sectional view that reveals a fan-shaped ring structure. A number of arcuate cylindrical grooves 223 are provided on all four sides of the concrete segment 222, excluding the arcuate surface. The tunnel lining segment 221 utilizes a number of arcuate cylindrical strips that match these arcuate cylindrical grooves 223 and are simultaneously inserted into the arcuate cylindrical grooves 223 on the short sides of the concrete segment 222 and connected circumferentially to form a single integrated structure.

[0059] Preferably, curved bolts are used instead of arc-shaped cylindrical bars to further improve the simulation effect.

[0060] It is worth noting that in this embodiment, the physical model scale is 1:30. In actual engineering, the concrete segments 222 have a thickness of 350 mm, an outer diameter of 6000 mm, and a width of 1500 mm. In simulation tests, the lining segment thickness was maintained at approximately 5% of the lining outer diameter to align with actual operating conditions.

[0061] The shield shell 210 is sleeved on the outside of the tunnel lining 220 .

[0062] The shield shell 210 and the tunnel lining 220 achieve relative sliding via the sealing adhesive sponge pad 230 adhered to the annular rectangular groove 211 , and the water-absorbing and expanding property of the sponge pad can effectively prevent the backflow of the shield tail mud.

[0063] The tunnel lining 220 can sequentially pass through the circular hole structure 111 on the front side and the circular hole structure 111 on the rear side of the model box body 110 at different inclination angles, and support the negative ring cover 130 .

[0064] The shield shell 210 is pulled out in reverse at a uniform speed and grouting is simultaneously performed into all the grouting holes 212 using an electric pump and a grouting pipe to simulate the excavation and synchronous grouting of a shield tunnel.

[0065] It is worth noting that in this embodiment, the thickness of the shield shell 210 and the grouting holes 212 in the scaled model were exaggerated to prevent grouting holes from being too small and causing slurry blockage. This factor was also included in the data analysis to avoid excessive test result errors. This exaggeration was not necessary for larger scale models.

[0066] The outer seams of the tunnel lining 220 are wrapped with waterproof tape to prevent the slurry from penetrating into the interior of the lining.

[0067] The outer wall of the shield casing 210 is provided with a pressure sensor and a displacement sensor. The inner wall of the tunnel lining is provided with a displacement sensor.

[0068] The sealing cover 120 and the negative ring cover 130 are both replaceable to simulate shield tunnels with different slopes. The sealing cover 120 and the negative ring cover 130 are both fixedly connected to the model box body 110 by bolts.

[0069] The sealing cover 120 and the negative ring cover 130 can correspond to each other one by one, and each can be taken as a group to accurately match shield tunnels with different inclination angles.

[0070] Example 8:

[0071] This embodiment provides a test method for a reverse multi-posture shield grouting simulation test device according to any one of Embodiments 1 to 7, comprising the following steps:

[0072] S1: Select the negative ring cover 130 that simulates the shield posture required for the test and fix it to the rear side of the model box 1 with bolts;

[0073] S2: Assemble the concrete segments 222 into tunnel lining segments 221, and then longitudinally connect them to form a tunnel lining 220. Then, put the shield shell 210 on the outside of the assembled tunnel lining 220 and pass through the front circular hole structure 111 and the rear circular hole structure 111 in sequence, so that the tunnel lining 220 rests against the bottom of the fixed negative ring cover 130. Then, select the corresponding sealing cover 120 to seal the remaining gap in the front circular hole structure.

[0074] S3: Install pressure and displacement sensors on the outer wall of the shield casing 210 and install displacement sensors on the inner wall of the tunnel lining 220;

[0075] S4: Fill the model box 1 with soil until it completely covers the shield tunnel, adjust the soil moisture content according to the test simulation requirements, and consolidate for a period of time;

[0076] S5: The test begins. While limiting the longitudinal displacement of the tunnel lining 220, the shield shell 210 is slowly pulled out in the reverse direction using an automated device. The pulled-out shield shell 210 is supported by a support. An electric pump and a grouting pipe are used to synchronously inject grout into the shield tail through the grouting hole 212 in a direction parallel to the tunnel centerline. Each distance a segment is moved is considered a step. After each step, wait for several hours.

[0077] S6: After the test is completed, the collected test data is imported into the computer for theoretical analysis.

[0078] The reverse multi-posture shield tunneling simulation test device can handle test simulations in various geological environments and simulate shield tunneling under various working conditions. Interchangeable sealing covers and negative ring covers adjust the longitudinal posture of the shield tunnel to accommodate different rock and soil types. The reverse extraction of the shield casing breaks the rigid design philosophy of shield experimental devices and reduces their complexity.

Claims

1. A reverse multi-posture shield grouting simulation test device, characterized by: It includes a model box (1) and a shield tunnel model (2); The model box (1) comprises a model box body (110), n sealing covers (120) and n negative ring covers (130); the model box body (110) is a rectangular box body with an open top; the four side walls of the model box body (110) are respectively marked as a first side wall, a second side wall, a third side wall and a fourth side wall; a through hole I (111) is arranged on the first side wall; the through hole I (111) comprises n circular holes overlapping in a vertical direction; the n circular holes have different inclination angles; different hollow portions are provided on the cover bodies of the n sealing covers (120); the sealing covers (120) are attached to the outer wall of the first side wall; the sealing covers (120) cover The cover is at the position of the through hole I (111), and the hollow portion of the i-th sealing cover (120) exposes the i-th circular hole; the third side wall is provided with a through hole II (1110); the through hole II (1110) is a circular hole; the negative ring cover (130) includes a cylindrical groove structure (133) and a circular ring plate (131); the n negative ring covers (130) have cylindrical groove structures (133) with different inclination angles; the circular ring plate (131) surrounds the outer periphery of the cylindrical groove structure (133); the cylindrical groove structure (133) is inserted into the inner cavity of the model box body (110) through the through hole II (1110); the circular ring plate (131) is attached to the outer wall of the third side wall; The shield tunnel model (2) comprises a shield shell model (210) and a tunnel lining model (220); the shield shell model (210) is a cylindrical structure; a pressure and displacement sensor is installed on the outer wall of the shield shell model (210); a plurality of grouting holes (212) are arranged on the shield shell model (210); the grouting holes (212) pass through both ends of the cylindrical wall of the shield shell model (210); the plurality of grouting holes (212) are evenly arranged along the circumference; the extending direction of the grouting holes (212) is parallel to the central axis of the shield shell model (210); the tunnel lining model (220) is a circular structure as a whole. The invention relates to a cylindrical structure; a displacement sensor is installed on the inner wall of the tunnel lining model (220); the tunnel lining model (220) can be split into a plurality of tunnel lining segments (221) along the longitudinal direction; the tunnel lining segment (221) is a cylindrical structure as a whole; the tunnel lining segment (221) can be split into a plurality of concrete segments (222) along the circumferential direction; the cross-sectional view of the concrete segment (222) is a fan-shaped ring structure as a whole; the shield shell model (210) is sleeved on the outer periphery of the tunnel lining model (220); the tunnel lining model (220) and the shield shell model (210) together constitute a simulated tunnel structure; During operation, the model box (1) is filled with soil; the simulated tunnel structure is buried in the soil; the two ends of the simulated tunnel structure respectively pass through the sealing cover (120) or the negative ring cover (130) and then extend out of the model box; the shield shell model (210) is pulled out in the reverse direction at a uniform speed to simulate the excavation of the shield tunnel, and grouting is simultaneously performed into the grouting hole (212) to simulate synchronous grouting; during the test, the corresponding sealing cover (120) and the negative ring cover (130) are replaced to simulate shield tunnels with different slope postures.

2. A reverse multi-posture shield grouting simulation test device according to claim 1, characterized in that: An embedding portion (121) is further provided on the side of the sealing cover (120) facing the first side wall; the embedding portion (121) is embedded in the through hole II (1110).

3. The reverse multi-posture shield grouting simulation test device according to claim 1 is characterized in that: Bolt holes (112) are arranged on the model box body (110), the sealing cover (120) and the negative ring cover (130); the sealing cover (120) and the model box body (110), as well as the negative ring cover (130) and the model box body (110) are fixedly connected by bolts.

4. The reverse multi-posture shield grouting simulation test device according to claim 1, characterized in that: The joints of adjacent tunnel lining segments (221) are provided with arc-shaped cylindrical grooves (223); the arc-shaped cylindrical strips are simultaneously inserted into the corresponding arc-shaped cylindrical grooves (223) of the adjacent tunnel lining segments (221).

5. The reverse multi-posture shield grouting simulation test device according to claim 1, characterized in that: Annular grooves (211) are arranged at intervals on the inner wall of the shield shell model (210); and sealing adhesive sponge pads (230) are pasted in the annular grooves.

6. The reverse multi-posture shield grouting simulation test device according to claim 1, characterized in that: The tunnel lining (220) model peripheral wall joints are wrapped with waterproof tape.

7. The test method of a reverse multi-posture shield grouting simulation test device according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1: Select the negative ring cover (130) that simulates the shield posture required for the test and fix it to the rear side of the model box (1) with bolts; S2: Assemble the concrete segments (222) into tunnel lining segments (221), and then longitudinally connect them into a section of tunnel lining (220). Then, put the shield shell (210) on the outside of the assembled tunnel lining (220), and pass through the front circular hole structure (111) and the rear circular hole structure (111) in sequence, so that the tunnel lining (220) is against the bottom of the fixed negative ring cover (130), and then select the corresponding sealing cover (120) to seal the remaining gap of the front circular hole structure; S3: Installing pressure and displacement sensors on the outer wall of the shield casing (210), and installing displacement sensors on the inner wall of the tunnel lining (220); S4: Fill the model box (1) with soil until it completely covers the shield tunnel, adjust the soil moisture content according to the test simulation requirements, and consolidate for a period of time; S5: The test begins. While limiting the longitudinal displacement of the tunnel lining (220), the shield shell (210) is slowly pulled out in the reverse direction using an automated device. The pulled-out shield shell (210) is supported by a support. An electric pump and a grouting pipe are used to synchronously inject grout into the shield tail through the grouting hole (212). The distance of each segment moved is considered a step in a direction parallel to the central axis of the tunnel. After each step is completed, a waiting time of several hours is required. S6: After the test is completed, the collected test data is imported into the computer for theoretical analysis.

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