Supergravity heavy rainfall simulation device and rainfall simulation method

Abstract

The invention discloses a supergravity heavy rainfall simulation device and a rainfall simulation method. The liquid inlet module is communicated with the rainfall model, the liquid inlet module is used for providing sprayed liquid for the soil body model of the rainfall model box and can control the liquid spraying speed, and viscous fluid is stored in the water supply box and used for simulating rainfall liquid and pore fluid; the method comprises the following steps: performing a constant gravity rainfall simulation test to obtain a hydraulic pressure-rainfall intensity relation curve when rainfall liquid is viscous fluid, simulating a similar scale of a rainfall supergravity test according to the viscous fluid, performing a centrifugal rainfall simulation test in a supergravity environment, and obtaining a transfer rule between rainfall intensity and prototype soil sample destructive performance. When the liquid with the viscosity coefficient higher than that of water is adopted as the rainfall simulation liquid, the effect of enhancing the rainfall intensity in the supergravity centrifugal test can be achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of geotechnical engineering, and in particular relates to a supergravity heavy rainfall simulation device and a rainfall simulation method. Background Art

[0002] Rainfall is one of the most typical and important climatic conditions that induce rock and soil disasters. It is a very important boundary condition in problems such as slope stability, dry-wet cycle of expansive soil, shallow foundation failure and embankment deformation. The spatial scale of rainfall-induced rock and soil disasters is large (regional scope) and the time span is long (seasonal dry-wet cycle, etc.), making it difficult to achieve complete on-site observations. Scaled model tests have become an indispensable means of reproduction. The centrifuge has "scale reduction" and "time reduction" effects. It can be used to simulate large-scale and long-term prototype rainfall problems and fully reproduce the slope instability process. When the gravity acceleration multiple N of the centrifuge is 100, the model scale is 1 / 100 of the actual prototype, and the rock and soil slope model simulation test time is shortened to 1 / 100 of the actual prototype. 2 The key to realizing centrifugal simulation of rainfall is the airborne device that can realistically simulate rainfall under hypergravity conditions.

[0003] At present, the airborne rainfall simulation device used for centrifugal testing mainly uses a specific type of nozzle. The test data provided by the manufacturer can tell the particle size of the droplets sprayed by the nozzle under a certain water pressure. Combined with components such as water pressure gauges and flow meters, quantitative simulation of rainfall intensity and duration within a certain range can be achieved through calibration. In the hypergravity test, in order to make the model rainfall intensity in the hypergravity environment equivalent to the prototype rainfall intensity, the test model rainfall intensity needs to be amplified to N times the prototype rainfall intensity. However, due to the characteristics of the ultragravity centrifuge test equipment, the traditional method of using an external pressure pump to increase the water pressure to simulate rainfall is often subject to many limitations. These include low water supply pressure of the pressure pump and excessively high requirements for the nozzle. These limitations make it impossible to simulate heavy rainfall under higher centrifugal acceleration g values. Summary of the invention

[0004] In order to solve the problems existing in the background technology, the purpose of the present invention is to provide a supergravity heavy rainfall simulation device and a rainfall simulation method to solve the problem that heavy rainfall cannot be simulated under higher centrifugal acceleration due to limitations such as the water supply pressure of the pressure pump.

[0005] The technical solution adopted by the present invention is: 1. A supergravity heavy rainfall simulation device: The invention comprises a liquid inlet module and a rainfall model box; a soil model is installed in the rainfall model box, a viscous fluid for simulating rainfall liquid is stored in the liquid inlet module, an outlet of the liquid inlet module is connected with an inlet of the rainfall model box, and the liquid inlet module is used for spraying liquid with controllable speed into the soil model of the rainfall model box, so as to simulate the deformation and destruction process of the soil model under rainfall conditions in a hypergravity environment, and then restore the destruction performance of the prototype soil sample under real rainfall conditions.

[0006] The liquid inlet module includes a water supply tank, an external pressure pump, a water pipe, a flow meter, a pressure regulating valve, a first water pressure sensor and a second water pressure sensor; the outlet of the water supply tank is connected to the liquid inlet of the rainfall model box through the water pipe, and the water pipe from the water supply tank to the rainfall model box is sequentially provided with an external pressure pump, a flow meter, a first water pressure sensor, a pressure regulating valve and a second water pressure sensor; The water supply tank stores viscous fluid, which is used to simulate rainfall liquid and pore fluid in the soil model. The external pressure pump is used to transport the viscous fluid stored in the water supply tank to the water pipe. The flow meter is used to monitor the flow in the water pipe in real time. The pressure regulating valve is used to adjust the liquid pressure in the water pipe. The first water pressure sensor and the second water pressure sensor are both used to monitor the liquid pressure in the water pipe in real time.

[0007] The rainfall model box includes a box body, a spray assembly and a soil model; the soil model is placed inside the box body, the spray assembly is installed on the top of the box body, the spray assembly is used to spray liquid on the soil model, the liquid in the water supply tank enters the spray assembly after passing through the water pipe, the pressure regulating valve adjusts the pressure of the liquid through the water pipe, and then adjusts the spraying speed of the liquid to simulate different rainfall intensities in a hypergravity environment.

[0008] The viscosity coefficient of the viscous fluid in the water supply tank is obtained according to the following formula: µ v =N·µ w Among them, µ v Indicates the viscosity coefficient of the viscous fluid in the water supply tank; µ w represents the viscosity coefficient of water; N represents the ratio of centrifugal acceleration to gravitational acceleration in a hypergravity environment.

[0009] 2. A method for simulating a high gravity heavy rainfall test, comprising the following steps: Step S1, first inject viscous fluid into the water supply tank, and start the water supply tank and the external pressure pump under normal gravity, so that the viscous fluid in the water supply tank flows into the rainfall model box through the water pipe; Step S2, using the pressure regulating valve to adjust the liquid pressure in the water pipe, and using the first water pressure sensor and the second water pressure sensor to monitor the liquid pressure in the water pipe in real time, when the liquid pressure in the water pipe reaches the set hydraulic target value and stabilizes, starting a rainfall simulation test under normal gravity to obtain the rainfall intensity in the rainfall model box; Step S3, changing the hydraulic target value, repeating step S2 multiple times, obtaining rainfall intensity under different hydraulic target values, and drawing a hydraulic pressure-rainfall intensity relationship curve of the viscous fluid with the set hydraulic target value as the abscissa and the rainfall intensity corresponding to the hydraulic target value as the ordinate; Step S4, hoisting the entire device into a geotechnical centrifuge to perform a centrifugal rainfall simulation test under a hypergravity environment; Step S5: In the centrifugal rainfall simulation test, microscopic observation is performed on the soil model in the rainfall model box to obtain the microscopic characteristics of the soil model at different positions, thereby restoring the destructive performance of the prototype soil sample under the actual working conditions under rainfall conditions, and obtaining the transmission law between the rainfall intensity and the destructive performance of the prototype soil sample.

[0010] The rainfall simulation test is specifically as follows: when the liquid in the water pipe reaches the set hydraulic target value and stabilizes after being regulated by the pressure regulating valve, the spray assembly on the top of the rainfall model box begins to spray liquid steadily to the soil model, and then observes the microscopic characteristics of the soil model during the liquid spraying process, and records the amount of sprayed liquid per unit time as the rainfall intensity of the rainfall model box.

[0011] The specific steps of step S4 are as follows: First, the entire device is hoisted into the geotechnical centrifuge and fixed, the geotechnical centrifuge is started, the centrifugal acceleration of the geotechnical centrifuge is gradually increased to the preset Ng and maintained for a preset time, and the water supply tank and the external pressure pump are started under Ng supergravity, so that the viscous fluid in the water supply tank flows into the rainfall model box through the water pipe. Then, the pressure regulating valve is used to adjust the liquid pressure in the water pipe, and the first water pressure sensor and the second water pressure sensor are used to monitor the liquid pressure in the water pipe in real time. When the liquid pressure in the water pipe reaches the set hydraulic target value and stabilizes, the centrifugal rainfall simulation test under supergravity is started.

[0012] Under the Ng supergravity, the viscous fluid in the water supply tank adopts a viscous fluid with a viscosity coefficient N times that of water.

[0013] In step S4, the hydraulic target value set in the water delivery pipe after pressure regulation by the pressure regulating valve is obtained by processing in the following manner: First, determine the rainfall intensity q of the prototype soil sample under the actual working conditions to be simulated p , according to the rainfall intensity q of the prototype soil sample p Determine the target rainfall intensity q of the soil model in the rainfall model boxm Then, the target rainfall intensity q is obtained by using the hydraulic pressure-rainfall intensity relationship curve of the viscous fluid m The corresponding hydraulic pressure is used as the set hydraulic target value, where the rainfall intensity q of the prototype soil sample is p and the target rainfall intensity q of the soil model m The relational expression is as follows: q m / q p = k m / k p k m = KρNg / µ v k p = Kρg / µ w Among them, k m is the soil permeability coefficient under the centrifugal acceleration of Ng; k p is the soil permeability coefficient under constant gravity; K is the soil inherent permeability coefficient; ρ is the fluid density; g is the gravitational acceleration; µ v Indicates the viscosity coefficient of the viscous fluid in the water supply tank; µ w Represents the viscosity of water.

[0014] The principle of the present invention is as follows: Under the Ng hypergravity test, the hydraulic gradient remains unchanged, and the ratio of the permeability coefficient of water between the soil model and the prototype under normal gravity is: k m / k p =(KρNg / µ) / (Kρg / µ)=N Among them, k m k is the soil permeability coefficient under centrifugal acceleration; p is the soil permeability coefficient under constant gravity; K is the soil inherent permeability coefficient; ρ is the fluid density; g is the gravitational acceleration; µ is the hydrodynamic viscosity coefficient; Ng represents the centrifugal acceleration; Under the same boundary conditions, the permeability coefficient of the soil in the centrifuge is N times the permeability coefficient of the soil under constant gravity, so the rainfall intensity is the same as the permeability coefficient of the soil, that is: q m / q p = N Among them, q m represents the rainfall intensity of the soil model; q p It indicates the rainfall intensity of the prototype soil sample; If a liquid with a density close to that of water but a viscosity N times that of water is used as the pore fluid, the ratio of the permeability coefficients of the soil model and the prototype soil sample is: k m / k p =(KρNg / Nµ) / (Kρg / µ)=N / N=1 Therefore, the ratio of rainfall intensity between the soil model and the prototype soil sample is q m / q p = 1, that is, by changing the liquid viscosity coefficient to reduce the soil permeability coefficient, when the test equipment is limited, the rainfall intensity can be equivalently increased to achieve the effect of simulating heavy rainfall.

[0015] According to the definition formula of rainfall intensity as the ratio of rainfall amount to rainfall time, the rainfall duration t of the prototype soil sample can be obtained: m The rainfall duration t of the model soil sample p for: t m =R m / q m t p =R p / q p Among them, t m represents the rainfall duration of the soil model; t p represents the rainfall duration of the prototype soil sample; R m Represents the rainfall of the soil model; R p represents the rainfall of the prototype soil sample and R p =NR m .

[0016] If a liquid with a density close to that of water but a viscosity coefficient N times that of water is used as the pore fluid, the ratio of rainfall duration of the soil model to that of the prototype soil sample is: t m / t p =1 / N Therefore, when a liquid with a viscosity N times that of water is used as the pore fluid and rainfall liquid, the simulated rainfall intensity can be effectively improved without changing the total rainfall in the soil model.

[0017] The present invention can effectively simulate different rainfall intensities in a hypergravity environment by adjusting the water outlet rate by changing the size of the pressure regulating valve. However, the simulation of heavy rainfall in a natural environment is often limited by the maximum pressure of the air compressor of the rainfall device. In order to effectively improve the problem of being unable to simulate heavy rainfall due to the limitation of the hypergravity test equipment, the purpose of the present invention is to achieve the effect of simulating heavy rainfall by using viscous fluid as rainfall liquid and porous fluid to change the scale of the hypergravity rainfall similarity law.

[0018] The beneficial effects of the present invention are: 1. The present invention achieves the simulation of heavy rainfall by replacing the viscous liquid to adjust the similarity scale of the model and prototype rainfall intensity without changing the rainfall device.

[0019] 2. The present invention adopts a liquid with a viscosity coefficient higher than that of water as a rainfall simulation liquid, which can achieve the effect of enhancing rainfall intensity in an ultra-gravity centrifugal test. The method of the present invention can solve the problem of difficulty in simulating higher rainfall intensities in centrifugal tests due to limitations of rainfall airborne devices.

[0020] 3. The present invention adopts a method of replacing the water source of the rainfall water supply tank with a liquid having a larger viscosity coefficient, thereby changing the rainfall similarity law. This method can also maximize the test simulation of heavy rainfall when the pressure regulation of the simulation test device is limited.

[0021] 4. Using viscous fluid to simulate rainfall hypergravity test can also effectively solve the contradiction between the similarity and inconsistency of the pore water pressure dissipation time and the particle movement time of the soil model under hypergravity environment, and achieve a simulation effect closer to reality. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the ultra-gravity centrifugal heavy rainfall simulation test device of the present invention; Figure 2 It is a schematic flow diagram of the ultra-gravity centrifugal heavy rainfall simulation test of the present invention; Figure 3 This is a schematic diagram of the simulation experiment process in a hypergravity environment; Figure 4 It is a schematic diagram of the placement of the ultra-gravity centrifugal heavy rainfall simulation test device in the centrifuge; Figure 5 It is a schematic diagram of an ultragravity centrifuge of the present invention.

[0023] In the figure: 1. Water supply tank; 2. External pressure pump; 3. Water pipe; 4. Micro flow meter; 5. Pressure regulating valve; 6. First water pressure sensor; 7. Second water pressure sensor; 8. Rainfall model box. DETAILED DESCRIPTION

[0024] The present invention is described in detail below in conjunction with specific implementation cases. The following implementation cases will help those skilled in the art to further understand the present invention, but will not limit the present invention in any form.

[0025] like Figure 1 As shown, the device includes a liquid inlet module and a rainfall model box 8; a soil model is installed in the rainfall model box 8, and a viscous fluid for simulating rainfall liquid is stored in the liquid inlet module. The outlet of the liquid inlet module is connected to the inlet of the rainfall model box 8, and the liquid inlet module is used to spray liquid with controllable speed into the soil model of the rainfall model box 8, so as to simulate the deformation and destruction process of the soil model under rainfall conditions in a hypergravity environment, thereby restoring the destructive performance of the prototype soil sample under real rainfall conditions.

[0026] The liquid inlet module includes a water supply tank 1, an external pressure pump 2, a water pipe 3, a flow meter 4, a pressure regulating valve 5, a first water pressure sensor 6 and a second water pressure sensor 7; the outlet of the water supply tank 1 is connected to the liquid inlet of the rainfall model box 8 through the water pipe 3, and the external pressure pump 2, the flow meter 4, the first water pressure sensor 6, the pressure regulating valve 5 and the second water pressure sensor 7 are sequentially arranged on the water pipe 3 from the water supply tank 1 to the rainfall model box 8; The water supply tank 1 stores viscous fluid, which is used to simulate rainfall liquid and pore fluid in the soil model. The external pressure pump 2 is used to transport the viscous fluid stored in the water supply tank 1 to the water pipe 3. The flow meter 4 is used to monitor the flow in the water pipe 3 in real time. The pressure regulating valve 5 is used to adjust the liquid pressure in the water pipe 3. The first water pressure sensor 6 and the second water pressure sensor 7 are both used to monitor the liquid pressure in the water pipe 3 in real time.

[0027] Specifically, the water supply tank 1 and the external pressure pump 2 are placed on the rotating arm of the centrifuge, and the flow meter 4, the pressure regulating valve 5, the first water pressure sensor 6, the second water pressure sensor 7 and the rainfall model box 8 are placed together in the centrifuge basket. The schematic diagram of the centrifuge in the specific implementation is shown in FIG. Figure 5 As shown. The first water pressure sensor 6 and the second water pressure sensor 7 are respectively located on both sides of the pressure regulating valve 5. The first water pressure sensor 6 can monitor the change of the liquid pressure in the water pipe 3 as the centrifugal acceleration value increases and stabilizes in real time. The liquid pressure in the water pipe 3 will increase sharply as the centrifugal acceleration value increases under the action of centrifugal force. The liquid pressure can be stabilized at the target value through the pressure reducing valve 5. The second water pressure sensor 7 can monitor the stabilized liquid pressure value in real time.

[0028] The rainfall model box 8 includes a box body, a spray assembly and a soil model; the soil model is placed inside the box body, the spray assembly is installed on the top of the box body, the spray assembly is used to spray liquid on the soil model, the liquid in the water supply tank 1 enters the spray assembly after passing through the water pipe 3, the pressure regulating valve 5 adjusts the liquid pressure through the water pipe 3, and then adjusts the spraying speed of the liquid to simulate different rainfall intensities in a hypergravity environment.

[0029] The viscosity coefficient of the viscous fluid in the water supply tank 1 is obtained by processing according to the following formula: µ v =N·µ w Among them, µ v Indicates the viscosity coefficient of the viscous fluid in the water supply tank 1; µ w represents the viscosity coefficient of water; N represents the ratio of centrifugal acceleration to gravitational acceleration in a hypergravity environment, and the density of the viscous fluid is consistent with that of water.

[0030] The embodiment of the present invention includes the following steps: Figure 2 As shown: Step S1: For a supergravity test with a preset centrifugal acceleration of Ng, firstly inject a viscous fluid into the water supply tank 1, and start the water supply tank 1 and the external pressure pump 2 under normal gravity, so that the viscous fluid in the water supply tank 1 flows into the rainfall model box 8 through the water pipe 6; Step S2, using the pressure regulating valve 5 to adjust the liquid pressure in the water pipe 3, and using the first water pressure sensor 6 and the second water pressure sensor 7 to monitor the liquid pressure in the water pipe 6 in real time. When the liquid pressure in the water pipe 6 reaches the set hydraulic target value and stabilizes, a rainfall simulation test under normal gravity is started to obtain the rainfall intensity in the rainfall model box 8; Step S3: Change the hydraulic target value, use the pressure regulating valve 5 to adjust the liquid pressure in the water pipe 3, repeat step S2 multiple times, obtain the rainfall intensity under different hydraulic target values, and plot the viscosity coefficient µ with the set hydraulic target value as the horizontal coordinate and the rainfall intensity corresponding to the hydraulic target value as the vertical coordinate. v The hydraulic pressure-rainfall intensity relationship curve of viscous fluid; Step S4: Figure 4 As shown, the device is hoisted into a geotechnical centrifuge as a whole to carry out a centrifugal rainfall simulation test under a hypergravity environment. The hydraulic target value in the centrifugal rainfall simulation test under a hypergravity environment is set according to the hydraulic pressure-rainfall intensity relationship curve of the viscous fluid; Step S5: In the centrifugal rainfall simulation test, microscopic observation is performed on the soil model in the rainfall model box 8 to obtain the microscopic characteristics and destructive performance of the soil model at different positions, and then the destructive performance of the prototype soil sample under the actual working conditions is restored under the rainfall conditions, and the transmission law between the rainfall intensity and the destructive performance of the prototype soil sample is obtained.

[0031] The rainfall simulation test is specifically as follows: when the liquid in the water pipe 3 reaches the set hydraulic target value and stabilizes after being pressure-regulated by the pressure-regulating valve 5, the spray assembly on the top of the rainfall model box 8 begins to stably spray liquid to the soil model, and then observes the microscopic characteristics of the soil model during the liquid spraying process to obtain the destructive performance of the soil model, and at the same time records the amount of sprayed liquid per unit time as the rainfall intensity of the rainfall model box 8.

[0032] Rainfall simulation tests include rainfall simulation tests under normal gravity and centrifugal rainfall simulation tests under hypergravity environments.

[0033] Specifically, the specific steps of step S4 are as follows: Figure 3 As shown: First, the entire device is hoisted into the geotechnical centrifuge and fixed, the geotechnical centrifuge is started, the centrifugal acceleration of the geotechnical centrifuge is gradually increased to a preset value Ng and maintained for a preset time, and the water supply tank 1 and the external pressure pump 2 are started under Ng supergravity, so that the viscous fluid in the water supply tank 1 flows into the rainfall model box 8 through the water pipe 6. Then, the pressure regulating valve 5 is used to adjust the liquid pressure in the water pipe 3, and the first water pressure sensor 6 and the second water pressure sensor 7 are used to monitor the liquid pressure in the water pipe 6 in real time. When the liquid pressure in the water pipe 6 reaches the set hydraulic target value and stabilizes, the centrifugal rainfall simulation test under supergravity is started.

[0034] Under Ng supergravity, the viscous fluid in the water supply tank 1 uses a viscous fluid with a viscosity coefficient N times that of water, and g is the gravitational acceleration.

[0035] That is, under Ng supergravity, the viscosity coefficient of the viscous fluid is obtained according to the following formula: µ v =N·µ w Among them, µ v Indicates the viscosity coefficient of the viscous fluid in the water supply tank 1; µ w represents the viscosity coefficient of water; N represents the ratio of centrifugal acceleration to gravitational acceleration in a hypergravity environment.

[0036] In step S4, the hydraulic target value set in the water delivery pipe 3 after the pressure regulation by the pressure regulating valve 5 is obtained by processing in the following manner: First, determine the rainfall intensity q of the prototype soil sample under the actual working conditions to be simulated p , according to the rainfall intensity q of the prototype soil sample p Determine the target rainfall intensity q of the soil model in the rainfall model box 8 m Then, the target rainfall intensity q is obtained by using the hydraulic pressure-rainfall intensity relationship curve of the viscous fluid m The corresponding hydraulic pressure is used as the set hydraulic target value, where the rainfall intensity q of the prototype soil sample is p and the target rainfall intensity q of the soil model m The relational expression is as follows: q m / q p = k m / k p k m = KρNg / µ v k p = Kρg / µ w Among them, k m is the soil permeability coefficient under the centrifugal acceleration of Ng; k pis the soil permeability coefficient under constant gravity; K is the soil inherent permeability coefficient; ρ is the fluid density; g is the gravitational acceleration; µ v Indicates the viscosity coefficient of the viscous fluid in the water supply tank 1; µ w Represents the viscosity of water.

[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A hypergravity heavy rainfall simulation device, characterized in that: The invention comprises a liquid inlet module and a rainfall model box (8); a soil model is installed in the rainfall model box (8); a viscous fluid for simulating rainfall liquid is stored in the liquid inlet module; an outlet of the liquid inlet module is connected to an inlet of the rainfall model box (8); the liquid inlet module is used to spray liquid with a controllable speed into the soil model of the rainfall model box (8), so as to simulate the deformation and failure process of the soil model under rainfall conditions in a hypergravity environment, thereby restoring the failure performance of the prototype soil sample under real rainfall conditions.

2. The device for simulating heavy rainfall under high gravity according to claim 1, characterized in that: The liquid inlet module comprises a water supply tank (1), an external pressure pump (2), a water pipe (3), a flow meter (4), a pressure regulating valve (5), a first water pressure sensor (6) and a second water pressure sensor (7); the outlet of the water supply tank (1) is connected to the liquid inlet of the rainfall model box (8) through the water pipe (3), and the external pressure pump (2), the flow meter (4), the first water pressure sensor (6), the pressure regulating valve (5) and the second water pressure sensor (7) are sequentially arranged on the water pipe (3) from the water supply tank (1) to the rainfall model box (8); The water supply tank (1) stores a viscous fluid, which is used to simulate rainfall liquid and pore fluid in a soil model. The external pressure pump (2) is used to transport the viscous fluid stored in the water supply tank (1) to the water pipe (3). The flow meter (4) is used to monitor the flow in the water pipe (3) in real time. The pressure regulating valve (5) is used to adjust the liquid pressure in the water pipe (3). The first water pressure sensor (6) and the second water pressure sensor (7) are both used to monitor the liquid pressure in the water pipe (3) in real time.

3. The device for simulating heavy rainfall under high gravity according to claim 2, characterized in that: The rainfall model box (8) comprises a box body, a liquid spraying assembly and a soil model; the soil model is placed inside the box body, the liquid spraying assembly is installed on the top of the box body, the liquid spraying assembly is used to spray liquid on the soil model, the liquid in the water supply box (1) enters the liquid spraying assembly after passing through the water pipe (3), the pressure regulating valve (5) adjusts the pressure of the liquid passing through the water pipe (3), and then adjusts the spraying speed of the liquid to simulate different rainfall intensities in a hypergravity environment.

4. The device for simulating heavy rainfall under high gravity according to claim 2, characterized in that: The viscosity coefficient of the viscous fluid in the water supply tank (1) is obtained by processing according to the following formula: µ v =N·µ w Among them, µ v represents the viscosity coefficient of the viscous fluid in the water supply tank (1); µ w represents the viscosity coefficient of water; N represents the ratio of centrifugal acceleration to gravitational acceleration in a hypergravity environment.

5. A method for simulating a high gravity heavy rainfall test applied to the device described in any one of claims 1 to 4, characterized in that: The following steps are involved: Step S1, first injecting a viscous fluid into the water supply tank (1), and starting the water supply tank (1) and the external pressure pump (2) under normal gravity, so that the viscous fluid in the water supply tank (1) flows into the rainfall model box (8) through the water pipe (6); Step S2, using the pressure regulating valve (5) to adjust the liquid pressure in the water pipe (3), and using the first water pressure sensor (6) and the second water pressure sensor (7) to monitor the liquid pressure in the water pipe (6) in real time, and when the liquid pressure in the water pipe (6) reaches the set hydraulic target value and stabilizes, starting a rainfall simulation test under normal gravity to obtain the rainfall intensity in the rainfall model box (8); Step S3, changing the hydraulic target value, repeating step S2 multiple times, obtaining rainfall intensity under different hydraulic target values, and drawing a hydraulic pressure-rainfall intensity relationship curve of the viscous fluid with the set hydraulic target value as the abscissa and the rainfall intensity corresponding to the hydraulic target value as the ordinate; Step S4, hoisting the entire device into a geotechnical centrifuge to perform a centrifugal rainfall simulation test under a hypergravity environment; Step S5, in the centrifugal rainfall simulation test, microscopic observation is performed on the soil model in the rainfall model box (8) to obtain the microscopic characteristics of the soil model at different positions, thereby restoring the destructive performance of the prototype soil sample under the actual working condition under the rainfall working condition, and obtaining the transmission law between the rainfall intensity and the destructive performance of the prototype soil sample.

6. A method for simulating a high gravity heavy rainfall test according to claim 5, characterized in that: The rainfall simulation test is specifically as follows: when the liquid in the water pipe (3) reaches the set hydraulic target value and stabilizes after being pressure-regulated by the pressure regulating valve (5), the liquid spraying assembly on the top of the rainfall model box (8) begins to stably spray liquid toward the soil model, then observes the microscopic characteristics of the soil model during the liquid spraying process, and simultaneously records the amount of liquid sprayed per unit time as the rainfall intensity of the rainfall model box (8).

7. A method for simulating a high gravity heavy rainfall test according to claim 5, characterized in that: The specific steps of step S4 are as follows: First, the device is hoisted into a geotechnical centrifuge as a whole and fixed, the geotechnical centrifuge is started, the centrifugal acceleration of the geotechnical centrifuge is gradually increased to a preset value Ng and maintained for a preset time, and the water supply tank (1) and the external pressure pump (2) are started under Ng supergravity, so that the viscous fluid in the water supply tank (1) flows into the rainfall model box (8) through the water pipe (6), then the liquid pressure in the water pipe (3) is adjusted by the pressure regulating valve (5), and the liquid pressure in the water pipe (6) is monitored in real time by the first water pressure sensor (6) and the second water pressure sensor (7), and when the liquid pressure in the water pipe (6) reaches the set hydraulic target value and stabilizes, the centrifugal rainfall simulation test under supergravity is started.

8. The method for simulating a high gravity heavy rainfall test according to claim 5, characterized in that: Under the Ng supergravity, the viscous fluid in the water supply tank (1) uses a viscous fluid with a viscosity coefficient N times that of water.

9. The method for simulating a high gravity heavy rainfall test according to claim 5, characterized in that: In step S4, the hydraulic target value set in the water delivery pipe (3) after pressure regulation by the pressure regulating valve (5) is obtained by processing in the following manner: First, determine the rainfall intensity q of the prototype soil sample under the actual working conditions to be simulated p , according to the rainfall intensity q of the prototype soil sample p Determine the target rainfall intensity q of the soil model in the rainfall model box (8) m Then, the target rainfall intensity q is obtained by using the hydraulic pressure-rainfall intensity relationship curve of the viscous fluid m The corresponding hydraulic pressure is used as the set hydraulic target value, where the rainfall intensity q of the prototype soil sample is p and the target rainfall intensity q of the soil model m The relational expression is as follows: q m / q p = k m / k p k m = KρNg / µ v k p = Kρg / µ w Among them, k m is the soil permeability coefficient under the centrifugal acceleration of Ng; k p is the soil permeability coefficient under constant gravity; K is the soil inherent permeability coefficient; ρ is the fluid density; g is the gravitational acceleration; µ v represents the viscosity coefficient of the viscous fluid in the water supply tank (1); µ w Represents the viscosity of water.

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