Subsea tunnel surrounding rock full life cycle test method based on supergravity geotechnical centrifugation technology

Abstract

The invention discloses a subsea tunnel surrounding rock full life cycle test method based on a supergravity geotechnical centrifuge technology, which comprises the following steps: firstly, constructing a model box, carrying out scale simulation on a subsea tunnel and a surrounding rock structure thereof, then putting the model box into a vacuum box for saturation treatment, finally taking the model box out of the vacuum box, putting the model box into a supergravity geotechnical centrifuge, and testing the whole life cycle of the subsea tunnel surrounding rock. And the super-gravity geotechnical centrifuge is started to rotate, and the strain sensor collects the dependent variable of the rock stratum near the tunnel reduced-scale pipeline in real time, so that the nonlinear elastic deformation of the rock stratum in the full life cycle in the running process of the train track simulation mechanism is observed. The model box is constructed to simulate the subsea tunnel and the surrounding rock structure thereof, test analysis is performed based on the supergravity geotechnical centrifugal technology, the evolution process of damage of the subsea tunnel and the surrounding rock structure thereof is remarkably accelerated, the experimental period is shortened, and the change condition of the whole life cycle is rapidly tested and determined.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of simulation test of seabed shield tunnel, and particularly relates to a test method for the whole life cycle of seabed tunnel surrounding rock based on supergravity geotechnical centrifugal technology. BACKGROUND

[0002] Due to the characteristics of high construction cost, long operation cycle, great difficulty and high cost of maintenance, etc., the performance evolution law of the lining structure and surrounding rock system of the seabed shield tunnel in the whole life cycle must be fully considered in the structural design stage. The existing method is to statistically analyze the performance evolution law according to historical data, but the existing historical data is less, and the statistical research data is not comprehensive, which is not suitable for the research and analysis of the performance evolution law of the whole life cycle of the seabed tunnel surrounding rock. SUMMARY

[0003] The technical problem to be solved by the present application is to provide a test method for the whole life cycle of seabed tunnel surrounding rock based on supergravity geotechnical centrifugal technology, which simulates the seabed tunnel and its surrounding rock structure by constructing a model box, and performs test analysis based on supergravity geotechnical centrifugal technology, thereby significantly accelerating the evolution process of the damage of the seabed tunnel and its surrounding rock structure, shortening the experimental cycle, and quickly testing and determining the change in the whole life cycle.

[0004] The technical scheme of the present application is as follows:

[0005] A test method for the whole life cycle of seabed tunnel surrounding rock based on supergravity geotechnical centrifugal technology, specifically comprising the following steps:

[0006] (1) Construct a model box, the model box comprising a box body, a wave-absorbing layer, a rock layer, seawater, a tunnel scale pipe, a strain sensor and a train track simulation mechanism; the wave-absorbing layer comprises a wave-absorbing layer plate completely covering the inner wall and the bottom plate of the box body and fixedly connected thereto, and a plurality of wave-absorbing strips completely covering the inner surface of the wave-absorbing layer plate and fixedly connected to the inner surface of the wave-absorbing layer plate in a zigzag shape, the long axis of the wave-absorbing strip being parallel to the long side of the box body, the plurality of wave-absorbing strips on the inner wall of the box body being arranged in parallel and completely covering the inner surface of the wave-absorbing layer plate, the plurality of wave-absorbing strips on the bottom plate of the box body being arranged in parallel along the width direction of the box body and completely covering the top surface of the wave-absorbing layer plate, the rock layer being arranged in the lower part of the box body, the seawater being arranged in the upper part of the box body, i.e. directly above the rock layer, the tunnel scale pipe being arranged in the rock layer and extending along the long side of the box body, the train track simulation mechanism being arranged in the tunnel scale pipe, and the strain sensor being arranged in the rock layer near the tunnel scale pipe;

[0007] (2) Place the model box in a vacuum box for saturation treatment, the vacuum box being provided with a vibration platform, the model box being arranged on the vibration platform, and the vibration platform being vibrated at low frequency synchronously while being vacuumized;

[0008] (3), after the vacuum is finished, the model box is taken out from the vacuum box, is placed in the basket of the super gravity geotechnical centrifuge, then starts the super gravity geotechnical centrifuge, after the super gravity geotechnical centrifuge runs stably, starts the train track simulation mechanism in the model box, and the strain sensor real-time acquisition strain of the rock layer near the tunnel scale pipeline in the whole life cycle of the rock layer in the process of running of the train track simulation mechanism, so that the nonlinear elastic deformation of the rock layer is observed.

[0009] The tunnel scale pipeline is arranged at the center position of the width direction of the rock layer in the box body, the width of the rock layer in the box body is L1, the outer diameter of the tunnel scale pipeline is L2, and the ratio of the two satisfies the following relationship: L1>k1*L2, and k1 is 4.2-5.9.

[0010] The plurality of wave-absorbing strips on the inner wall of the box body are all in the shape of a right triangle in the longitudinal section, one of the right angles of the wave-absorbing strip is a vertical surface, and the other is a horizontal surface, the vertical surface of the wave-absorbing strip is fixedly connected to the inner surface of the wave-absorbing layer plate, and the horizontal surface of the wave-absorbing strip above the horizontal central axis of the tunnel scale pipeline faces upward, and the horizontal surface of the wave-absorbing strip below the horizontal central axis of the tunnel scale pipeline faces downward; the plurality of wave-absorbing strips on the bottom plate of the box body are all in the shape of an isosceles triangle in the longitudinal section, the bottom surface of the wave-absorbing strip is fixedly connected to the top surface of the wave-absorbing layer plate, and the top angle of the wave-absorbing strip faces upward, and a plurality of bottom supporting strips in the shape of a semicircle in the longitudinal section are further fixedly connected to the bottom surface of the wave-absorbing layer plate on the bottom plate of the box body, the plurality of bottom supporting strips are arranged in parallel along the width direction of the box body and completely cover the bottom surface of the wave-absorbing layer plate, and the top end surface of the bottom supporting strip is fixedly connected to the bottom surface of the wave-absorbing layer plate.

[0011] The wave-absorbing layer plate and the wave-absorbing strip are both made of polyurethane porous foam material, and the bottom supporting strip is made of ferrite rubber.

[0012] The width of the horizontal surface of each wave-absorbing strip on the inner wall of the box body and the height of each wave-absorbing strip on the bottom plate of the box body are both L3, the height of the vertical surface of each wave-absorbing strip on the inner wall of the box body, the width of the bottom surface of each wave-absorbing strip on the bottom plate of the box body and the diameter of each bottom supporting strip are all L4, and the ratio of the two satisfies the following relationship: L4=k2*L3, the value of k2 is 0.41-0.62 under the super centrifugal force of 100 g, and the value of k2 is 0.51-0.72 under the super centrifugal force of 100-300 g.

[0013] The strain sensor is a Bragg fiber grating strain sensor.

[0014] The train track simulation mechanism comprises a slide rail extending along the long axis of the tunnel scale pipeline, a sliding block slidingly arranged on the slide rail, a load loading mechanism arranged on the sliding block, and a control mechanism for driving the sliding block to move along the slide rail and regulating the load loading mechanism.

[0015] The model box is placed in the vacuum box for saturation treatment, and the time T for vacuumizing satisfies the following formula (1):

[0016] T=k3*V1 / P (1);

[0017] In formula (1), V1 represents the internal volume of the vacuum box, P represents the pressure for vacuumizing, k3 is a harmonic coefficient, and the value of k3 is M·L -4 ·T -1 , M·L -4 ·T -1 , wherein M represents a mass unit, L represents a length unit, and T represents a time unit.

[0018] The vibration frequency of the vibration platform during vacuumizing is 0.2-1 Hz.

[0019] The strain sensor collects the strain of the rock layer near the tunnel scale pipeline in real time, and the stress load σ of the rock layer near the tunnel scale pipeline is calculated by the following formula (2):

[0020]

[0021] In formula (2), ε is the strain of the rock layer near the tunnel scale pipeline collected by the strain sensor in real time, E1 is the theoretical modulus of the rock layer, which is a constant value, E2 is the modulus of the rock layer after disturbance and crushing, which is a constant value, H is 0.86-1.32, t is time, n is the multiple of the gravity acceleration g in the super gravity centrifuge after starting, and k4 is 0.12-1.25.

[0022] Then, the stress load σ calculated by formula (2) is compared with the average yield stress σ y of the rock layer.

[0023] When σ<σ y , the rock near the tunnel scale pipeline does not reach the acceleration node of fatigue, and the stress load σ satisfies the following formula (3):

[0024]

[0025] In formula (3), the value of k5 is 0.23-1.32. is the first derivative of the stress load σ; is the first derivative of the strain ε; and w1 is the viscosity coefficient of the first stage of the rock layer to be solved.

[0026] When v≥σ y , the rock near the tunnel scale pipeline enters the acceleration stage of fatigue, and the stress load σ satisfies the following formula (4):

[0027]

[0028] In formula (4), k6 is 1.23-1.68; w2 is a second stage, i.e., an acceleration stage, of the rock layer to be solved.

[0029] Advantages of the present application:

[0030] (1) The present application uses the technology of supergravity scale and time reduction, simulates the seabed tunnel and its surrounding rock structure by constructing a model box, sets a tunnel scale pipeline and a train track simulation mechanism in the rock layer, simulates the operation process of the seabed tunnel and establishes the process of high-frequency loading of the slider, thereby testing the state of the change of the surrounding rock mass around the tunnel in the whole life cycle of the seabed tunnel surrounding rock, and testing in a supergravity geotechnical centrifuge, improving the gravitational acceleration, simulating the service state of the segment under the complex stress boundary, significantly accelerating the damage evolution process of the structure, so that the model box can be equivalent to simulate the service process of the prototype seabed tunnel structure for decades or even hundreds of years in a supergravity field in a short time, greatly shortening the experimental period.

[0031] (2) The present application sets a wave-absorbing layer on the inner wall and the bottom plate of the model box to absorb the vibration generated in the operation process of the train track simulation mechanism, avoid the reflection of the vibration wave on the inner wall and the bottom plate of the model box, and cause the change of the cumulative stress in the rock layer, and interfere with the test.

[0032] (3) Since the train track simulation mechanism in the tunnel scale pipeline is located at the center position of the width direction of the model box, the excited wave mainly propagates in the radial direction along the tunnel scale pipeline to the external rock layer, considering that there is a certain incidence angle between the propagation direction of the train track simulation mechanism running vibration wave and the inner wall of the box, in order to improve the absorption efficiency and reduce the reflection phenomenon, the wave-absorbing strip is designed as a triangular structure, thereby realizing effective absorption of vibration waves of different frequencies and different incidence angles, and simulating a more realistic wave attenuation process.

[0033] (4) The present application cannot realize complete internal saturation by only putting seawater into the model box, so low-frequency vibration is accompanied in the process of vacuumizing, which facilitates the complete extraction of the bubbles in the rock layer, so that the seawater can completely infiltrate all the gaps, thereby improving the authenticity of the seabed tunnel surrounding rock simulation.

[0034] (5), the application establishes the rock mass damage formula (formula 2-formula 4) of the whole life cycle of the surrounding rock of the submarine tunnel, and obtains the viscous coefficients of the rock mass in two different stages in combination with the test, the viscous coefficient of the rock mass is a key parameter for describing the time-dependent mechanical behavior of the rock mass, the viscous coefficients of the two different stages will change obviously, and when the change is serious, the bearing capacity of the surrounding rock of the tunnel which has been put into operation will be threatened, the viscous coefficient is a physical bridge connecting the transient response and long-term time-varying behavior of the rock mass, provides a quantitative basis for the tunnel life prediction, and has important significance for the excavation, construction and operation of the tunnel engineering. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 is the front view of the model box of the application.

[0036] Figure 2 is the side view of the model box of the application.

[0037] Figure 3 is the structural schematic diagram of the tunnel scale pipeline inside the wave absorbing layer of the application.

[0038] The drawings show that: 1-box, 2-wave absorbing layer, 3-rock layer, 4-sea water, 5-tunnel scale pipeline, 6-train track simulation mechanism, 7-control mechanism, 21-wave absorbing layer plate, 22-wave absorbing strip, 23-bottom support strip. DETAILED DESCRIPTION

[0039] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, not all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the application.

[0040] A test method for the whole life cycle of the surrounding rock of the submarine tunnel based on the supergravity geotechnical centrifuge technology, specifically comprising the following steps:

[0041] (1), see Figure 1 and Figure 2 , a model box is constructed, the model box comprises a box body 1, a wave absorbing layer 2, a rock layer 3, sea water 4, a tunnel scale pipeline 5, a Bragg fiber grating strain sensor and a train track simulation mechanism 6;

[0042] The wave-absorbing layer 2 is arranged on the inner wall and the bottom plate of the box 1, the rock layer 3 is arranged at the lower part in the box 1, the seawater 4 is arranged at the upper part in the box 1, i.e. directly above the rock layer 3, the tunnel scale pipeline 5 (formed by splicing pipe segments) is arranged at the central position in the width direction of the rock layer 3 and extends along the long side of the box 1, the train track simulation mechanism 6 is arranged in the tunnel scale pipeline 5, the train track simulation mechanism 6 comprises a sliding rail extending along the long axis of the tunnel scale pipeline 5, a sliding block slidingly arranged on the sliding rail, a load loading mechanism arranged on the sliding block, and a control mechanism driving the sliding block to move along the sliding rail and regulating the load loading mechanism, the control mechanism 7 is arranged outside the tunnel scale pipeline 5, and the Bragg fiber grating strain sensor is arranged in the rock layer 3 near the tunnel scale pipeline 5;

[0043] The width of the rock layer 3 in the box 1 is L1, the outer diameter of the tunnel scale pipeline 5 is L2, and the ratio of the two satisfies the following relationship: L1>k1*L2, and the value of k1 is 4.2-5.9;

[0044] See Figure 3 The wave-absorbing layer 2 comprises a wave-absorbing layer plate 21 completely covering and fixedly connected to the inner wall and the bottom plate of the box 1, and a plurality of wave-absorbing strips 22 in a zigzag shape covering and fixedly connected to the inner surface of the wave-absorbing layer plate 21, the long axis of the wave-absorbing strip 22 is parallel to the long side of the box 1, the plurality of wave-absorbing strips 22 on the inner wall of the box 1 are arranged in parallel in the up-down direction and completely cover the inner surface of the wave-absorbing layer plate 21, and the plurality of wave-absorbing strips 22 on the bottom plate of the box 1 are arranged in parallel in the width direction of the box 1 and completely cover the top surface of the wave-absorbing layer plate 21; the longitudinal section of each of the plurality of wave-absorbing strips 22 on the inner wall of the box 1 is a right triangle, one of the right angles of the wave-absorbing strip 22 is a vertical surface, and the other is a horizontal surface, the vertical surface of the wave-absorbing strip 22 is fixedly connected to the inner surface of the wave-absorbing layer plate 21, and the horizontal surface of the wave-absorbing strip 22 above the horizontal central axis of the tunnel scale pipeline 5 faces upward, and the horizontal surface of the wave-absorbing strip 22 below the horizontal central axis of the tunnel scale pipeline 5 faces downward; the longitudinal section of each of the plurality of wave-absorbing strips 22 on the bottom plate of the box 1 is an isosceles triangle, the bottom surface of the wave-absorbing strip 22 is fixedly connected to the top surface of the wave-absorbing layer plate 21, and the top corner of the wave-absorbing strip 22 faces upward, and a plurality of bottom support strips 23 with a semicircular longitudinal section are further fixedly connected to the bottom surface of the wave-absorbing layer plate 21 on the bottom plate of the box 1, the plurality of bottom support strips 23 are arranged in parallel in the width direction of the box 1 and completely cover the bottom surface of the wave-absorbing layer plate 21, and the top end surface of the bottom support strip 23 is fixedly connected to the bottom surface of the wave-absorbing layer plate 21; the wave-absorbing layer plate 21 and the wave-absorbing strip 22 are made of polyurethane porous foam material, and the bottom support strip 23 is made of ferrite rubber; the wave-absorbing layer plate 21 and the wave-absorbing strip 22 are used for absorbing vibration waves in the running process of the train track simulation mechanism 6, and the bottom support strip 23 is used for absorbing the vibration of the hanging basket bottom surface caused by unbalanced force in the running process of the super gravity geotechnical centrifuge;

[0045] The ratio of the height of each wave-absorbing strip 22 on the inner wall of the box 1 to the width of the horizontal plane of each wave-absorbing strip 22 on the bottom plate of the box 1 is L3, the ratio of the height of each wave-absorbing strip 22 on the inner wall of the box 1 to the height of the vertical plane of each wave-absorbing strip 22 on the bottom plate of the box 1 is L4, and the ratio of the width of the bottom surface of each wave-absorbing strip 22 on the bottom plate of the box 1 to the diameter of each bottom supporting strip 23 is L4, and the ratio satisfies the following formula: L4=k2*L3, wherein the value of k2 is 0.41-0.62 under an ultracentrifugal force of 100 g, and the value of k2 is 0.51-0.72 under an ultracentrifugal force of 100-300 g;

[0046] (2) The model box is placed in a vacuum box for saturation treatment, the vacuum box is provided with a vibrating platform, the model box is arranged on the vibrating platform, and the vibrating platform is synchronously vibrated at a low frequency (vibration frequency: 0.2-1 Hz) while being vacuumized, and the time T of vacuumization satisfies the following formula (1):

[0047] T=k3*V1 / P (1);

[0048] In formula (1), V1 represents the internal volume of the vacuum box, P represents the pressure of vacuumization, k3 is a harmonic coefficient, and the value of k3 is M·L -4 ·T -1 , M·L -4 ·T -1 , wherein M represents a mass unit, L represents a length unit, and T represents a time unit;

[0049] (3) After the vacuumization is completed, the model box is taken out of the vacuum box and placed in a basket of the supergravity soil centrifuge, then the supergravity soil centrifuge is started, after the supergravity soil centrifuge is stably operated, the train track simulation mechanism in the model box is started, the Bragg fiber grating strain sensor collects the strain of the rock layer near the tunnel scale pipeline in real time, so that the nonlinear elastic deformation of the rock layer in the whole life cycle in the running process of the train track simulation mechanism is observed, and the stress load σ borne by the rock layer near the tunnel scale pipeline is calculated according to the following formula (2):

[0050]

[0051] In formula (2), ε is the strain of the rock layer near the tunnel scale pipeline collected by the strain sensor in real time, E1 is the theoretical modulus of the rock layer, E2 is the modulus of the rock layer after disturbance and crushing, H is 0.86-1.32, t is time, n is the multiple of the gravity acceleration g in the supergravity environment after the supergravity soil centrifuge is started, and the value of k4 is 0.12-1.25;

[0052] Then, the stress load σ calculated according to formula (2) is compared with the average yield stress σ y of the rock layer, and the average yield stress σy is a known constant value;

[0053] When σ < σ y , the rock near the tunnel scale pipe does not reach the accelerated node of fatigue, and the stress load σ satisfies the following formula (3) :

[0054]

[0055] In formula (3), the value of k5 is 0.23-1.32; is the first derivative of the stress load σ; is the first derivative of the strain ε; w1 is the viscosity coefficient of the first stage of the rock layer to be solved;

[0056] When σ ≥ σ y , the rock near the tunnel scale pipe enters the accelerated stage of fatigue, and the stress load σ satisfies the following formula (4) :

[0057]

[0058] In formula (4), the value of k6 is 1.23-1.68; w2 is the viscosity coefficient of the second stage, i.e. the accelerated stage, of the rock layer to be solved.

[0059] Although the embodiments of the present application have been shown and described, it can be understood by those skilled in the art that various changes, modifications, replacements and variations can be made to the embodiments without departing from the principles and spirits of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A method for testing the surrounding rock of a submarine tunnel throughout its entire life cycle based on high-gravity geotechnical centrifuge technology, characterized by: The specific steps include: (1) Constructing a model box, the model box includes a box body, an absorbing layer, a rock layer, seawater, a tunnel scale pipe, a strain sensor and a train track simulation mechanism; the absorbing layer includes an absorbing layer plate whose outer surface is completely covered and fixedly connected to the inner wall and bottom plate of the box body, and a plurality of serrated absorbing strips covering and fixedly connected to the inner surface of the absorbing layer plate, the long axis of the absorbing strips is parallel to the long side of the box body, the plurality of absorbing strips on the inner wall of the box body are arranged in parallel up and down and completely cover the inner surface of the absorbing layer plate, the plurality of absorbing strips on the bottom plate of the box body are arranged in parallel along the width direction of the box body and completely cover the top surface of the absorbing layer plate, the rock layer is arranged in the lower part of the box body, the seawater is arranged in the upper part of the box body, that is, directly above the rock layer, the tunnel scale pipe is arranged in the rock layer and the tunnel scale pipe extends along the long side of the box body, the train track simulation mechanism is arranged in the tunnel scale pipe, and the strain sensor is arranged in the rock layer near the tunnel scale pipe; (2) placing the model box in a vacuum box for saturation treatment, wherein a vibration platform is provided in the vacuum box, and the model box is placed on the vibration platform. While vacuuming, the vibration platform is synchronously vibrated at a low frequency; (3) After the vacuuming is completed, the model box is taken out of the vacuum box and placed in the basket of the high-gravity geotechnical centrifuge. Then the high-gravity geotechnical centrifuge is started. After the high-gravity geotechnical centrifuge runs smoothly, the train track simulation mechanism in the model box is started. The strain sensor collects the strain of the rock layer near the tunnel scale pipe in real time, thereby observing the nonlinear elastic deformation of the rock layer throughout its life cycle during the operation of the train track simulation mechanism.

2. The method for testing the surrounding rock of a submarine tunnel throughout its entire life cycle based on high gravity geocentrifuge technology according to claim 1, characterized in that: The tunnel scale pipe is set at the center position of the rock layer in the width direction. The width of the rock layer in the box is L1, and the outer diameter of the tunnel scale pipe is L2. The ratio of the two satisfies the following relationship: L1>k1×L2, and the value of k1 is 4.2~5.

9.

3. The method for testing the surrounding rock of a submarine tunnel throughout its entire life cycle based on high gravity geocentrifuge technology according to claim 2, characterized in that: The multiple absorbing strips on the inner wall of the box are all right-angled triangles in longitudinal cross-section, one of the right-angled outer surfaces of the absorbing strip is a vertical surface, and the other right-angled outer surface is a horizontal surface, the vertical surface of the absorbing strip is fixedly connected to the inner surface of the absorbing layer plate, and the horizontal surface of the absorbing strip above the horizontal central axis of the tunnel scale pipe faces upward, and the horizontal surface of the absorbing strip below the horizontal central axis of the tunnel scale pipe faces downward; the multiple absorbing strips on the bottom plate of the box are all isosceles triangles in longitudinal cross-section, the bottom surface of the absorbing strip is fixedly connected to the top surface of the absorbing layer plate, and the top angle of the absorbing strip faces upward, and a plurality of bottom support strips with a semicircular longitudinal cross-section are also fixedly connected to the bottom surface of the absorbing layer plate on the bottom plate of the box, the plurality of bottom support strips are arranged in parallel along the width direction of the box and completely cover the bottom surface of the absorbing layer plate, and the top plane of the bottom support strip is fixedly connected to the bottom surface of the absorbing layer plate.

4. The method for testing the surrounding rock of a submarine tunnel throughout its entire life cycle based on high gravity geocentrifuge technology according to claim 3, characterized in that: The wave-absorbing layer plate and the wave-absorbing strip are both made of polyurethane porous foam material, and the bottom support strip is made of ferrite rubber.

5. The method for testing the surrounding rock of a submarine tunnel throughout its entire life cycle based on high gravity geocentrifuge technology according to claim 3, characterized in that: The horizontal width of each absorbing strip on the inner wall of the box and the height of each absorbing strip on the bottom plate of the box are both L3, the vertical height of each absorbing strip on the inner wall of the box, the bottom width of each absorbing strip on the bottom plate of the box and the diameter of each bottom support strip are all L4, and the ratio of the two satisfies the following relationship: L4=k2×L3, under the ultracentrifugal force of 100g, the value of k2 is 0.41~0.62, and under the ultracentrifugal force of 100-300g, the value of k2 is 0.51~0.

72.

6. The method for testing the surrounding rock of a submarine tunnel throughout its entire life cycle based on high gravity geocentrifuge technology according to claim 1, characterized in that: The strain sensor is a Bragg fiber grating strain sensor.

7. The method for testing the surrounding rock of a submarine tunnel throughout its entire life cycle based on high gravity geocentrifuge technology according to claim 1, characterized in that: The train track simulation mechanism includes a slide rail extending along the long axis of the tunnel scale pipe, a slider sliding on the slide rail, a load loading mechanism arranged on the slider, and a control mechanism for driving the slider to move along the slide rail and regulating the load loading mechanism.

8. The method for testing the surrounding rock of a submarine tunnel throughout its entire life cycle based on high gravity geocentrifuge technology according to claim 1, characterized in that: When the model box is placed in a vacuum box for saturation treatment, the vacuuming time T satisfies the following formula (1): T = k3 × V1 / P (1); In formula (1), V1 represents the internal volume of the vacuum box, P represents the vacuum pressure, and k3 is the harmonic coefficient. The value of k3 is 2.4~24.1M·L -4 ·T -1 , M.L. -4 ·T -1 The M represents the unit of mass, L represents the unit of length, and T represents the unit of time.

9. The method for testing the surrounding rock of a submarine tunnel throughout its entire life cycle based on high gravity geocentrifuge technology according to claim 1, characterized in that: During the vacuuming, the vibration frequency of the vibration platform is 0.2-1 Hz.

10. The method for testing the surrounding rock of a submarine tunnel throughout its entire life cycle based on high gravity geocentrifuge technology according to claim 1, characterized in that: The strain sensor collects the strain of the rock layer near the tunnel scale pipe in real time, and calculates the stress load σ borne by the rock near the tunnel scale pipe by the following formula (2); In formula (2), ε is the strain of the rock layer near the tunnel scale pipe collected in real time by the strain sensor, E1 is the theoretical modulus of the rock layer, which is a constant value; E2 is the modulus of the rock layer after disturbance and crushing, which is a constant value; H is 0.86~1.32; t is time; n is the multiple of the gravitational acceleration g in the hypergravity environment after the hypergravity geotechnical centrifuge is started; k4 is 0.12~1.25; Then the stress load σ calculated by formula (2) is compared with the average yield stress σ of the rock layer y Make a comparison; When σ<σ y When , the rock near the tunnel scale pipe has not reached the fatigue acceleration node, and the stress load σ satisfies the following formula (3): In formula (3), the value of k5 is 0.23~1.32; is the first derivative of stress load σ; is the first-order derivative of the strain variable ε; w1 is the viscosity coefficient of the first stage of the rock layer to be solved; When σ≥σ y When , the rock near the tunnel scale pipe enters the accelerated fatigue stage, and the stress load σ satisfies the following formula (4): In formula (4), k6 is 1.23 to 1.68; w2 is the viscosity coefficient of the rock layer to be solved in the second stage, i.e., the acceleration stage.

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