Device and method for testing water and soil pressure of seabed shield tunnel under tidal action

Abstract

The invention provides a device and a method for testing water and soil pressure of a seabed shield tunnel under tidal action. The device comprises a C-shaped workbench; the sealing mechanism is located at the bottom in the C-shaped opening and comprises a silo structure and a top cover plate, and a sealing gasket is arranged between the top cover plate and the silo structure; a soil body is arranged in the silo structure, and a water inlet hole and a groove are formed in the top cover plate; the simulation tunnel structure is located in the silo structure; the top loading mechanism is located at the top in the C-shaped opening; the water pressure loading mechanism is used for providing a simulated tide load; the pore water pressure measuring mechanism is used for measuring pore water pressure of soil layers at different heights of the soil body; the water pressure gauge is used for measuring water pressure load around the simulated tunnel structure, and the earth pressure gauge is used for measuring earth pressure load around the simulated tunnel structure; and a control device. According to the invention, the influence rule of seabed shield tunnel water and soil pressure by tidal action and the influence depth of pore water pressure in an overlying stratum by tidal action can be simulated.

Description

Technical Field

[0001] The invention relates to the technical field of shield tunnel engineering, and in particular to a device and method for testing water and soil pressure of a submarine shield tunnel under tidal action. Background Art

[0002] Under the influence of tides, the water level in submarine tunnels fluctuates regularly. The fluctuating water level will bring about a changing seepage field, which in turn will cause the stress field to change in time and space, making the distribution of water and soil pressure in the tunnel extremely complex. With the rapid increase in the number of submarine shield tunnel projects in my country in recent years, the influence of tides, strong storm surges and other fluctuating water levels on submarine tunnels has become a hot research topic.

[0003] The existing submarine shield tunnel structure design mainly simulates the tidal effect by introducing the assumption of equal water head or equal water pressure changes outside the lining, without considering factors such as burial depth and stratum characteristics. At present, the law of water and soil pressure changes in submarine shield tunnels under tidal action is unclear, and the existing devices cannot simulate the magnitude and law of the influence of sea tidal action on the soil pressure and water pressure load around the submarine shield tunnel. There is a lack of simulation devices and methods for the depth of the pore water pressure of the overlying strata of the submarine shield tunnel affected by the tidal action. Summary of the invention

[0004] In view of the defects in the prior art, the object of the present invention is to provide a device and method for testing water and soil pressure of a submarine shield tunnel under tidal action.

[0005] According to one aspect of the present invention, there is provided a device for testing water and soil pressure of a submarine shield tunnel under tidal action, comprising:

[0006] A C-shaped workbench having a C-shaped opening;

[0007] A sealing mechanism is located at the bottom of the C-shaped opening, the sealing mechanism comprises a silo structure and a top cover plate arranged above the silo structure, a sealing gasket is arranged between the top cover plate and the silo structure; a soil body simulating the stratum characteristics around the tunnel is arranged inside the silo structure, and a water inlet hole and a groove used as a water storage space are arranged on the top cover plate;

[0008] A simulated tunnel structure, located inside the silo structure, for simulating a submarine shield tunnel;

[0009] A top loading mechanism, located at the top of the C-shaped opening, the top loading mechanism applies a predetermined load to the sealing mechanism;

[0010] A water pressure loading mechanism connected to the water inlet, the water pressure loading mechanism is used to provide a simulated tidal load;

[0011] A pore water pressure measuring mechanism is provided in the silo structure, and is used to measure the pore water pressure of soil layers at different heights of the soil body;

[0012] A water pressure gauge and an earth pressure gauge are arranged on the outer surface of the simulated tunnel structure, wherein the water pressure gauge is used to measure the water pressure load around the simulated tunnel structure, and the earth pressure gauge is used to measure the earth pressure load around the simulated tunnel structure;

[0013] The control device is respectively connected with the top loading mechanism, the water pressure loading mechanism, the pore water pressure measuring mechanism, the water pressure gauge and the soil pressure gauge.

[0014] Optionally, the water pressure loading mechanism comprises:

[0015] A water pressure pipeline, one end of which is connected to the water inlet hole;

[0016] The hydraulic cylinder is connected to the other end of the hydraulic pipeline and is used to provide loading water pressure.

[0017] Optionally, the control device controls the hydraulic cylinder to apply a water pressure fluctuation load according to a planned tidal fluctuation law.

[0018] Optionally, the pore water pressure measuring mechanism comprises:

[0019] A threading tube, which passes through the top loading mechanism and the top cover plate in sequence and is vertically inserted into the silo structure, and one end of the threading tube is located at the top of the simulated tunnel structure;

[0020] A plurality of brackets are fixed on the threading tube along the length direction of the threading tube, and the brackets are located inside the silo structure;

[0021] A plurality of piezometers are respectively fixed on the threading tubes, and the piezometers are used to measure the pore water pressure at corresponding positions.

[0022] Optionally, a plurality of the piezometers are evenly spaced from the top of the soil in the silo structure to the top of the simulated tunnel structure.

[0023] Optionally, the simulated tunnel structure is a cylindrical concrete shell.

[0024] Optionally, the soil body is a similar material prepared according to the physical and mechanical properties and permeability characteristics of the original soil layer.

[0025] According to another aspect of the present invention, a method for testing water and soil pressure of a submarine shield tunnel under tidal action is provided, which is implemented by using the above-mentioned device for testing water and soil pressure of a submarine shield tunnel under tidal action, and the method comprises:

[0026] The simulated tunnel structure is placed in the silo structure, a pore water pressure measuring mechanism is installed in the silo structure, and a water pressure gauge and an earth pressure gauge are laid on the outer surface of the simulated tunnel structure;

[0027] Place soil into the silo structure;

[0028] Paste the sealing gasket between the top cover and the silo structure, and place the top cover on top of the silo structure;

[0029] Adjust the top loading mechanism to apply a predetermined load to the sealing mechanism;

[0030] Loading the water pressure to a predetermined water pressure through a water pressure loading mechanism;

[0031] The control device controls the water pressure loading mechanism to apply water pressure fluctuation load according to the predetermined tidal fluctuation law, and records the measured values ​​of the pore water pressure measuring mechanism, water pressure gauge and earth pressure gauge in real time to obtain the law of the influence of tidal action on water and soil pressure of submarine shield tunnel and the depth of tidal action on pore water pressure in overlying strata.

[0032] Furthermore, the method also includes: replacing the soil in the silo structure, repeating the test, and obtaining the law of the influence of tidal action on the water and soil pressure of the submarine shield tunnel and the depth of the influence of tidal action on the pore water pressure of the overlying strata under different stratum conditions.

[0033] Furthermore, the method also includes: adjusting the height of the simulated tunnel structure within the silo structure or the thickness of the soil inside the silo structure, repeating the test, and obtaining the law of the influence of tidal effects on the water and soil pressure of the submarine shield tunnel and the depth of the influence of tidal effects on the pore water pressure of the overlying strata at different burial depths.

[0034] Compared with the prior art, the present invention has at least one of the following beneficial effects:

[0035] 1. The present invention adjusts the water pressure loading mechanism through a control device to achieve simulated tidal loads. Through the mutual cooperation between the sealing mechanism, simulated tunnel structure, top loading mechanism, pore water pressure measuring mechanism, water pressure gauge and earth pressure gauge, it is possible to simulate the influence of tidal effects on water and soil pressure in submarine shield tunnels and the depth of tidal effects on pore water pressure in overlying strata.

[0036] 2. The present invention can simulate the depth of pore water pressure in the overlying strata of the shield tunnel and the water and soil pressure of the high-pressure submarine shield tunnel affected by tidal action under different stratum conditions by replacing the soil in the silo structure.

[0037] 3. The present invention can simulate the influence of tidal effects on water and soil pressure in submarine shield tunnels and the depth of influence of tidal effects on pore water pressure in overlying strata at different burial depths by adjusting the height of the simulated tunnel structure in the silo structure or the thickness of the soil inside the silo structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0039] Figure 1 It is an overall front view of a device for testing water and soil pressure of a submarine shield tunnel under tidal action in one embodiment of the present invention;

[0040] Figure 2 It is an overall right side view of a device for testing water and soil pressure of a submarine shield tunnel under tidal action in one embodiment of the present invention;

[0041] The corresponding reference numerals in the figure are: 1 is a C-type workbench, 2 is a top oil cylinder, 3 is a pad, 4 is a top cover plate, 5 is a sealing gasket, 6 is a silo structure, 7 is a simulated tunnel structure, 8 is a threading pipe, 9 is a bracket, 10 is a hydraulic cylinder, 11 is a hydraulic pipeline, 12 is a piezometer, 13 is a water pressure gauge, 14 is a soil pressure gauge, and 15 is a control device. DETAILED DESCRIPTION

[0042] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several variations and improvements may be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0043] It should be noted that, in the present application, the orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "front", "back", "vertical", "horizontal", "side", "bottom", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only a relational word determined for the convenience of describing the structural relationship of each component or element of the present application, and does not specifically refer to any component or element in the present application, and cannot be understood as a limitation on the present application. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" can explicitly or implicitly include one or more of the features. Moreover, the terms "first", "second", etc. are used to distinguish similar objects, and do not have to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described here can be implemented in an order other than that illustrated or described here.

[0044] In this application, terms such as "fixed connection", "connected", "connection", etc. should be understood in a broad sense, indicating that it can be fixedly connected, integrally connected or detachably connected; it can be directly connected or indirectly connected through an intermediate medium. Relevant technicians in this field can determine the specific meanings of the above terms in this application according to specific circumstances, and they should not be understood as limitations on this application.

[0045] Reference Figure 1 and Figure 2The device for testing water and soil pressure of a submarine shield tunnel under tidal action provided by an embodiment of the present invention can simulate the law of water and soil pressure of a submarine shield tunnel under tidal action and the depth of pore water pressure of the overlying strata affected by tidal action. The device comprises a C-type workbench 1, a sealing mechanism, a simulated tunnel structure 7, a top loading mechanism, a water pressure loading mechanism, a pore water pressure measuring mechanism, a water pressure gauge 13, an earth pressure gauge 14 and a control device 15; the C-type workbench 1 has a C-type opening, the C-type workbench 1 is welded from steel plates, and the middle and lower parts provide an operating platform for the test; the sealing mechanism is located at the bottom of the C-type opening, the sealing mechanism comprises a silo structure 6 and a top cover plate 4 covering the silo structure 6, and a sealing gasket 5 is provided between the top cover plate 4 and the silo structure 6; a soil body simulating the characteristics of the strata around the tunnel is provided inside the silo structure 6, and a water inlet hole and a groove used as a water storage space are provided on the top cover plate 4; the simulated tunnel structure 7 is located at the silo structure 6. , which is used to simulate an undersea shield tunnel; the top loading mechanism is located at the top of the C-shaped opening, the top loading mechanism applies a predetermined load to the sealing mechanism, and the middle and upper part of the C-shaped workbench 1 provides a reaction force for the displacement loading of the top loading mechanism; the water pressure loading mechanism is connected to the water inlet hole, and the water pressure loading mechanism is used to provide a simulated tidal load; the pore water pressure measuring mechanism is arranged in the silo structure 6, and the pore water pressure measuring mechanism is used to measure the pore water pressure of soil layers at different heights of the soil body; the water pressure gauge 13 and the earth pressure gauge 14 are arranged on the outer surface of the simulated tunnel structure 7, the water pressure gauge 13 is used to measure the water pressure load around the simulated tunnel structure 7, and the earth pressure gauge 14 is used to measure the earth pressure load around the simulated tunnel structure 7; the control device 15 is respectively connected to the top loading mechanism, the water pressure loading mechanism, the pore water pressure measuring mechanism, the water pressure gauge 13 and the earth pressure gauge 14, and the control device 15 controls the water pressure loading mechanism to realize automatic water pressure loading, which can simulate the effect of tidal load.

[0046] In some embodiments, the top cover plate 4 and the lower silo structure 6 of the sealing mechanism are both made of steel. The top cover plate 4 has an annular groove on the outer periphery, and the lower silo structure 6 also has an annular groove on the upper periphery for pasting the sealing gasket 5. Exemplarily, the sealing gasket 5 is an EPDM rubber sealing gasket; the space inside the silo structure 6 is for filling simulated soil; the middle groove on the top of the top cover plate 4 is used as a water storage space to simulate the water pressure load of tidal seawater; the top cover plate 4 is also provided with air vents, which can prevent the existence of air pressure in the water storage space, thereby improving the accuracy of the test results.

[0047] In some embodiments, the hydraulic loading mechanism includes a hydraulic pipeline 11 and a hydraulic cylinder 10, one end of the hydraulic pipeline 11 is connected to the water inlet; the hydraulic cylinder 10 is connected to the other end of the hydraulic pipeline 11 to provide loading water pressure.

[0048] In some embodiments, the control device 15 controls the hydraulic cylinder 10 to apply a water pressure fluctuation load according to a predetermined tidal fluctuation law. Specifically, the simulation of the tidal load is achieved through the pressure conversion of the hydraulic cylinder 10, that is, by servo-controlling the hydraulic cylinder (i.e., the hydraulic cylinder 10), adjusting the running direction of the hydraulic cylinder, and driving the piston plate of the hydraulic cylinder to compress the liquid to generate a predetermined water pressure, thereby providing a tidal change water pressure load.

[0049] In some embodiments, the top loading mechanism includes four top oil cylinders 2 and a pad 3 located below the top oil cylinders 2. The four top oil cylinders 2 are used to apply a predetermined load to the sealing gasket 5. The upper part of the opening of the C-shaped workbench 1 is welded and fixed to the top oil cylinder 2 to provide support for the top oil cylinder 2. By applying the top load, pressure is applied to the sealing gasket 5 to seal the water (high-pressure water) in the groove of the top cover plate 4; the size of the top load is related to the type and size of the selected sealing gasket 5, and can be determined by a conventional sealing gasket test.

[0050] In some embodiments, the pore water pressure measuring mechanism includes a threading tube 8, a plurality of brackets 9 and a plurality of piezometers 12. The threading tube 8 passes through the top loading mechanism and the top cover plate 4 in sequence and is vertically inserted into the silo structure 6. One end of the threading tube 8 is located at the top of the simulated tunnel structure 7, and the other end is located at the top of the silo structure 6. Exemplarily, the threading tube 8 is a threading steel tube, and the bracket 9 is a steel bracket. The plurality of brackets 9 are fixed on the threading tube 8 along the length direction of the threading tube 8. The bracket 9 is located inside the silo structure 6 and is used to fix the threading tube 8. The plurality of piezometers 12 are respectively fixed on the threading tube 8. For example, the piezometers 12 are tied to the threading tube 8 by ropes. The piezometers 12 are used to measure the pore water pressure at the corresponding position. A pressure measuring hole is reserved on the top cover plate 4. The wire of the piezometer 12 passes through the threading tube 8 and is led out from the top cover plate 4 through the pressure measuring hole.

[0051] The number of piezometers 12 is determined according to the thickness of the simulated test soil layer, and one piezometer 12 can be set at a certain interval. In some embodiments, multiple piezometers 12 are evenly distributed from the top of the silo structure 6 to the top of the simulated tunnel structure 7, and one piezometer 12 can be set at intervals of 0.5m.

[0052] Exemplarily, the threading pipe 8 is a φ50 stainless steel pipe, extending from the top of the silo structure 6 to the top of the simulated tunnel structure 7. No piezometers 12 are provided at the upper and lower end points of the threading pipe 8, and it is fixed with three transverse steel brackets. The steel brackets and the steel pipes, and the steel brackets and the inner surface of the silo structure 6 are fixed by welding. The pore water pressure measuring mechanism includes 5 piezometers 12, and the 5 piezometers 12 are evenly arranged along the height direction on the threading pipe 8 inside the silo structure 6.

[0053] In some embodiments, the simulated tunnel structure 7 is a cylindrical concrete shell. For example, the simulated tunnel structure 7 is circular with a radius of 0.3m, made of C60 concrete, and has a waterproof grade not less than P12. The simulated tunnel structure 7 can be located at the bottom of the silo structure 6, or can be placed at other heights according to test requirements.

[0054] In some embodiments, the soil body is a similar material prepared in a certain proportion using quartz sand, barite powder, talcum powder, cement, vaseline, silicone oil and water according to the physical and mechanical properties and permeability characteristics of the original soil layer.

[0055] Specifically, the permeability coefficient of the soil is mainly adjusted by the ratio of vaseline and silicone oil; the permeability coefficient similarity scale C K , Geometric Similarity Scale C L Similar to bulk density C γ The similarity relationship between them is:

[0056]

[0057] The control device 15 as an automated operating mechanism may include a desk and a computer, and various test parameters may be set on the computer to achieve automated operation.

[0058] The device provided by the above-mentioned embodiment of the present invention adjusts the water pressure loading mechanism through a control device to achieve simulated tidal loads. Through the mutual coordination between the sealing mechanism, the simulated tunnel structure, the top loading mechanism, the pore water pressure measuring mechanism, the water pressure gauge and the earth pressure gauge, it can simulate shield tunnels under different formation conditions, the law of the effects of the surrounding soil pressure and the water pressure load on the segment structure under the action of sea tides, and the depth at which the pore water pressure of the overlying strata of the submarine shield tunnel is affected by the tidal action, so as to reasonably determine the load of the submarine shield tunnel under the action of tides.

[0059] Based on the same inventive concept, another embodiment of the present invention provides a method for testing water and soil pressure of a submarine shield tunnel under tidal action, which is implemented by using the above-mentioned device for testing water and soil pressure of a submarine shield tunnel under tidal action. The method comprises:

[0060] S1. Place the simulated tunnel structure in the silo structure, install a pore water pressure measuring mechanism in the silo structure. For example, the pore water pressure measuring mechanism includes 5 piezometers. A water pressure gauge and an earth pressure gauge are laid on the outer surface of the simulated tunnel structure, and both are installed and fixed on the outer surface of the simulated tunnel structure.

[0061] S2. Place soil into the lower silo structure. The soil is the original soil of the research object or the material prepared through similar experiments.

[0062] S3. Paste the sealing gasket into the annular groove between the top cover plate and the silo structure, and place the top cover plate above the silo structure;

[0063] S4, adjusting the top loading mechanism to apply a predetermined load to the sealing mechanism;

[0064] S5. After the hydraulic pipeline is connected, the hydraulic cylinder is started, and the water pressure is gradually loaded to a predetermined water pressure through the hydraulic loading mechanism; the predetermined water pressure corresponds to the water pressure under normal conditions, that is, the water pressure is loaded to a static water level when there is no tide;

[0065] S6. The control device controls the water pressure loading mechanism to apply water pressure fluctuation load according to the proposed tidal fluctuation law, simulates the tidal load effect, and records the measurement values ​​of the piezometer, water pressure gauge and earth pressure gauge of the pore water pressure measuring mechanism in real time, and measures the real-time water and soil pressure at each monitoring location respectively. The control device analyzes the test data to obtain the law of the influence of sea tides on the water and soil pressure of the submarine shield tunnel, as well as the depth of the pore water pressure in the overlying strata affected by the tidal effect.

[0066] Taking into account the influence of formation characteristics, in a further embodiment, the above method also includes: replacing the soil in the silo structure, repeating the test, and obtaining the law of the influence of tidal action on the water and soil pressure of the submarine shield tunnel and the depth of the influence of tidal action on the pore water pressure of the overlying formation under different formation conditions.

[0067] In a further embodiment, the above method also includes: adjusting the height of the simulated tunnel structure in the silo structure, repeating the test, and obtaining the law of the influence of tidal effects on the water and soil pressure of the submarine shield tunnel and the depth of the influence of tidal effects on the pore water pressure of the overlying strata at different burial depths.

[0068] In some other embodiments, by changing the thickness of the soil inside the silo structure, the influence of tidal effects on the water and soil pressure of the submarine shield tunnel and the depth of influence of tidal effects on the pore water pressure of the overlying strata at different burial depths can be obtained.

[0069] The above-mentioned embodiment of the present invention adjusts the water pressure loading mechanism through the control device to realize the simulation of tidal load. Through the mutual coordination between the sealing mechanism, the simulated tunnel structure, the top loading mechanism, the pore water pressure measuring mechanism, the water pressure gauge and the earth pressure gauge, it is possible to simulate the law of the influence of tidal action on the water and soil pressure of the submarine shield tunnel and the depth of the pore water pressure in the overlying stratum affected by the tidal action.

[0070] The above embodiment of the present invention can simulate the depth of the pore water pressure in the overlying strata of the shield tunnel and the water and soil pressure of the high-pressure submarine shield tunnel under different stratum conditions by replacing the soil in the silo structure. By adjusting the height of the simulated tunnel structure in the silo structure or the thickness of the soil, it is possible to simulate the law of the influence of the tidal effect on the water and soil pressure of the submarine shield tunnel and the depth of the tidal effect on the pore water pressure of the overlying strata under different burial depths.

[0071] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various modifications or variations within the scope of the claims, which does not affect the essence of the present invention. The above preferred features can be used in any combination without conflicting with each other.

Claims

1. A device for testing water and soil pressure of submarine shield tunnel under tidal action, characterized in that: include: A C-shaped workbench having a C-shaped opening; A sealing mechanism is located at the bottom of the C-shaped opening, the sealing mechanism comprises a silo structure and a top cover plate arranged above the silo structure, a sealing gasket is arranged between the top cover plate and the silo structure; a soil body simulating the stratum characteristics around the tunnel is arranged inside the silo structure, and a water inlet hole and a groove used as a water storage space are arranged on the top cover plate; A simulated tunnel structure, located inside the silo structure, for simulating a submarine shield tunnel; A top loading mechanism, located at the top of the C-shaped opening, the top loading mechanism applies a predetermined load to the sealing mechanism; A water pressure loading mechanism connected to the water inlet, the water pressure loading mechanism is used to provide a simulated tidal load; A pore water pressure measuring mechanism is provided in the silo structure, and is used to measure the pore water pressure of soil layers at different heights of the soil body; A water pressure gauge and an earth pressure gauge are arranged on the outer surface of the simulated tunnel structure, wherein the water pressure gauge is used to measure the water pressure load around the simulated tunnel structure, and the earth pressure gauge is used to measure the earth pressure load around the simulated tunnel structure; The control device is respectively connected with the top loading mechanism, the water pressure loading mechanism, the pore water pressure measuring mechanism, the water pressure gauge and the soil pressure gauge.

2. The water and soil pressure test device for submarine shield tunnel under tidal action according to claim 1 is characterized in that: The water pressure loading mechanism comprises: A water pressure pipeline, one end of which is connected to the water inlet hole; The hydraulic cylinder is connected to the other end of the hydraulic pipeline and is used to provide loading water pressure.

3. The water and soil pressure test device for submarine shield tunnel under tidal action according to claim 2 is characterized in that: The control device controls the hydraulic cylinder to apply the water pressure fluctuation load according to the proposed tidal fluctuation law.

4. The water and soil pressure test device for submarine shield tunnel under tidal action according to claim 1 is characterized in that: The pore water pressure measuring mechanism comprises: A threading tube, which passes through the top loading mechanism and the top cover plate in sequence and is vertically inserted into the silo structure, and one end of the threading tube is located at the top of the simulated tunnel structure; A plurality of brackets are fixed on the threading tube along the length direction of the threading tube, and the brackets are located inside the silo structure; A plurality of piezometers are respectively fixed on the threading tubes, and the piezometers are used to measure the pore water pressure at corresponding positions.

5. The water and soil pressure test device for submarine shield tunnel under tidal action according to claim 4 is characterized in that: The plurality of piezometers are evenly distributed from the top of the soil in the silo structure to the top of the simulated tunnel structure.

6. The water and soil pressure test device for submarine shield tunnel under tidal action according to claim 1 is characterized in that: The simulated tunnel structure is a cylindrical concrete shell.

7. The water and soil pressure test device for submarine shield tunnel under tidal action according to claim 1 is characterized in that: The soil body is a similar material prepared according to the physical and mechanical properties and permeability characteristics of the original soil layer.

8. A method for testing water and soil pressure of a submarine shield tunnel under tidal action, characterized in that: The method is implemented by using the water and soil pressure test device for submarine shield tunnel under tidal action as described in any one of claims 1 to 7, and the method comprises: The simulated tunnel structure is placed in the silo structure, a pore water pressure measuring mechanism is installed in the silo structure, and a water pressure gauge and an earth pressure gauge are laid on the outer surface of the simulated tunnel structure; Place soil into the silo structure; Paste the sealing gasket between the top cover and the silo structure, and place the top cover on top of the silo structure; Adjust the top loading mechanism to apply a predetermined load to the sealing mechanism; Loading the water pressure to a predetermined water pressure through a water pressure loading mechanism; The control device controls the water pressure loading mechanism to apply water pressure fluctuation load according to the predetermined tidal fluctuation law, and records the measured values ​​of the pore water pressure measuring mechanism, water pressure gauge and earth pressure gauge in real time to obtain the law of the influence of tidal action on water and soil pressure of submarine shield tunnel and the depth of tidal action on pore water pressure in overlying strata.

9. The method for testing water and soil pressure of a submarine shield tunnel under tidal action according to claim 8 is characterized in that: Also includes: By replacing the soil in the silo structure and repeating the test, we can obtain the influence of tidal action on the water and soil pressure of the submarine shield tunnel and the depth of influence of tidal action on the pore water pressure of the overlying strata under different stratum conditions.

10. The method for testing water and soil pressure of a submarine shield tunnel under tidal action according to claim 8, characterized in that: Also includes: By adjusting the height of the simulated tunnel structure within the silo structure or the thickness of the soil inside the silo structure and repeating the test, we can obtain the influence of tidal effects on the water and soil pressure of the submarine shield tunnel and the depth of influence of tidal effects on the pore water pressure of the overlying strata at different burial depths.

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