Dynamic slope angle adjustment test device and method applicable to high hypergravity

Abstract

Disclosed in the present invention is a dynamic slope angle adjustment test device and method applicable to high hypergravity. A model box support system and an angle adjustment system are both connected to an external hoisting bottom plate; an instability model box is used for the placement of a soil mass model, and the instability model box is hinged to the model box support system; an accumulation model box is movably mounted on the angle adjustment system; the instability model box is lapped onto the accumulation model box; and the angle adjustment system is externally connected to a control system. The method comprises: assembling the device, and placing the soil mass model inside the instability model box; hoisting the device as a whole into a geotechnical centrifuge, so as to perform a dynamic slope angle adjustment test in a hypergravity environment; and observing the soil mass model inside the instability model box during the dynamic slope angle adjustment test, thus reproducing the slope failure behaviors of a prototype soil sample under an actual working situation at different gradients. The present invention can reproduce a process of slope instability, sliding and decelerated accumulation, and has characteristics such as a large angle adjustment range, a stable angular inclination rate and good controllability.

Description

A test device and method for dynamic adjustment of slope angle under high gravity. Technical Field

[0001] This invention belongs to the technical field of geotechnical engineering testing equipment, specifically relating to a dynamic slope angle adjustment test device and method suitable for high gravity. Background Technology

[0002] Loose-accumulated slopes are prone to instability under heavy rainfall and external loads, resulting in reduced shear strength and overall instability. After instability, landslides exhibit high mobility, significant destructive force, and a wide impact range. Physical experiments addressing this engineering problem of slope instability face challenges such as complex and difficult-to-trigger triggering conditions, long sliding distances after failure, extremely high and difficult-to-restore stresses at the moment of instability, and difficulties in dynamically adjusting slope angles under hypergravity conditions. Therefore, using hypergravity experiments to simulate long-distance slope instability and sliding failure triggering under restored stress conditions under hypergravity is crucial.

[0003] The slope inclination adjustment device can be used to study the seismic performance of tailings dams, underwater slope instability caused by static liquefaction, shear characteristics of loose saturated sand, and the sliding process of landslide bodies along the sliding bed after slope instability under hypergravity conditions. It is particularly significant for understanding slope instability mechanisms, developing disaster prevention and mitigation measures, and optimizing engineering design. Researching slope failure under different triggering modes helps reveal critical slope, instability modes, and changes in soil mechanical properties, providing a scientific basis for slope design, reducing landslide risk, and offering targeted guidance for reinforcement measures.

[0004] Existing slope inclination adjustment test devices under hypergravity have problems such as limited adjustable angle of the model (0-20°), low applicable hypergravity g value (below 15g, and the inclination angle change is achieved by motor drive, which is not suitable for high hypergravity, or hydraulically driven hydraulic cylinder tilting to bear bending moment), and complex experimental device that often relies on external oil source to achieve device lifting and adjustment. Summary of the Invention

[0005] In order to solve the problems existing in the background technology, the purpose of this invention is to provide a dynamic slope angle adjustment test device and method suitable for hypergravity, so as to overcome the problems of complex device structure, difficulty in monitoring prototype test device, limited adjustable angle of model test device, difficulty in controlling the tilt angle of model box, complex experimental device with external oil source, and inability to trigger slope instability under hypergravity.

[0006] The technical solution adopted in this invention is as follows:

[0007] I. A test device for dynamic adjustment of slope angle suitable for high-gravity environments:

[0008] It includes an unstable model box, a stacking model box, a model box support system, and an angle adjustment system. The bottom ends of the model box support system and the angle adjustment system are fixedly connected to an external lifting base plate, which is placed in the basket of the centrifuge. The unstable model box is used to hold the soil model. The bottom end of the unstable model box is hinged to the top of the model box support system, which can swing up and down. The stacking model box is installed on the angle adjustment system, which can move up and down. The unstable model box is attached to the stacking model box. The angle adjustment system is connected to an external control system.

[0009] The angle adjustment system includes three guide column assemblies, three support cylinders, cylinder clamp assemblies, synchronous oil release valves, hydraulic synchronizers, and support cylinder reset hydraulic pumps.

[0010] The bottom ends of the guide column assembly and the support cylinder are vertically fixed to the hoisting base plate. The tops of the guide column assembly and the support cylinder are connected by the cylinder clamp assembly. The rodless chambers of the three support cylinders are respectively connected to the upper chambers of the three independent chambers of the hydraulic synchronizer. The lower chambers of the three independent chambers of the hydraulic synchronizer are all connected through the first plate ball valve and the synchronous oil release valve. The rod chambers of the three support cylinders are all connected to the support cylinder reset hydraulic pump. The synchronous oil release valve and the support cylinder reset hydraulic pump are both connected to the hydraulic oil tank in the model box support system.

[0011] The top of the guide column assembly and the top of the support cylinder are fixedly connected to the bottom of the stacking model box. The angle adjustment system is used to precisely control the lifting and lowering of the stacking model box through the telescopic support cylinder, thereby precisely controlling the angle change value and angle change rate of the unstable model box attached to the stacking model box in a hypergravity environment.

[0012] The hydraulic pump for resetting the supporting cylinders includes a second plate ball valve, a gear pump, a motor, and a relief valve. Both the motor and the relief valve are connected to the gear pump. The second plate ball valve has three oil passages: the first passage is connected to the independent rod chamber of each of the three supporting cylinders; the second passage is connected to the hydraulic oil outlet of the gear pump; and the third passage is connected to the hydraulic oil tank in the model box support system. The first plate ball valve also has three oil passages: the first passage is connected to the lower chamber of the three independent oil chambers of the hydraulic synchronizer; the second passage is connected to the hydraulic oil outlet of the gear pump; and the third passage is connected to the inlet of the synchronous drain valve. Both the gear pump and the relief valve are connected to the hydraulic oil tank in the model box support system.

[0013] The model box support system includes a rotating shaft, bearing housing, upper top plate, guide column assembly, height adjustment screw assembly, and hydraulic oil tank;

[0014] The bottom of the hydraulic oil tank is fixedly connected to the lifting base plate. The bottom of the telescopic guide column assembly and the height adjustment screw assembly are both fixedly connected to the hydraulic oil tank. The top of the guide column assembly and the height adjustment screw assembly are both fixedly connected to the lower surface of the upper top plate. The bearing seat is fixedly installed on the upper top plate. The rotating shaft is rotatably installed on the bearing seat around its own axis. The first model box bottom plate of the unstable model box is hinged to the rotating shaft of the model box support system.

[0015] The unstable model box includes a rear baffle, a first observation window, a first model box bottom plate, two first model box side plates, an upper connecting plate, a transition plate, and a transition plate rotation shaft. The bottom ends of the rear baffle and the two first model box side plates are fixedly connected to the first model box bottom plate. The two first model box side plates are arranged symmetrically, and both ends of the rear baffle are connected to the two first model box side plates respectively. The top front ends of the two first model box side plates are connected by the upper connecting plate. The front end of the first model box bottom plate is hinged to the transition plate through the transition plate rotation shaft. The soil model is placed on the first model box bottom plate. A first observation window for observing the soil model is provided in the middle of the first model box side plate. The transition plate of the unstable model box overlaps at the opening of the stacked model box.

[0016] The bottom plate of the first model box has a groove in the middle, and the bottom plate of the first model box is hinged to the rotating shaft of the model box support system at the groove.

[0017] The stacking model box includes a second observation window, a second model box bottom plate, two second model box side plates, and a front baffle. The bottom ends of the front baffle and the two second model box side plates are fixedly connected to the second model box bottom plate. The two second model box side plates are arranged symmetrically, and the two ends of the front baffle are respectively connected to the two second model box side plates. A second observation window for observing the soil model is provided in the middle of the second model box side plate.

[0018] The transition plate of the unstable model box overlaps the bottom plate of the second model box. The guide column assembly and support cylinder in the angle adjustment system are fixedly connected to the lower surface of the bottom plate of the second model box. The angle adjustment system is used to adjust the height of the stacked model box, thereby changing the tilt angle of the unstable model box overlapping the stacked model box.

[0019] The instability model box in the angle adjustment system is equipped with tilt sensors, and both the tilt sensors and the hydraulic pump for resetting the support cylinder are connected to an external control system.

[0020] II. A test method for dynamic adjustment of slope angle suitable for high-gravity environments, comprising the following steps:

[0021] Step S1, Model Making: Place the soil model inside the unstable model box. After the soil model is made, install the unstable model box on the model box support system.

[0022] Step S2: Hoist the device into the basket of the geotechnical centrifuge to conduct a dynamic slope adjustment test under hypergravity conditions;

[0023] Step S3: In the slope angle dynamic adjustment test, the soil model in the unstable model box is observed to obtain the failure performance of the soil model under different slopes, and then the failure performance of the prototype soil sample under different slopes under real working conditions is restored.

[0024] The specific steps of step S2 are as follows:

[0025] First, the hoisting base plate equipped with the test device is hoisted into the centrifuge and fixed. Under constant gravity, two of the three oil passages in the first and second plate ball valves are opened to start the centrifuge. The centrifuge acceleration is gradually increased to a preset Ng and maintained for a preset time. At the same time, the oil discharge rate of the synchronous oil discharge valve is controlled, causing the piston rod of the support cylinder to move up and down. The piston rod of the support cylinder drives the stacking model box to move up and down synchronously, thereby changing the tilt angle of the unstable model box and the soil model. Then, the destructive performance of the soil model is observed at different tilt angles.

[0026] In step S2, the specific method by which two of the three oil passages in the first and second plate ball valves are controlled to be open, so that the piston rod of the supporting cylinder can move up and down, is as follows:

[0027] When the device is subjected to a slope angle dynamic adjustment test under hypergravity conditions of g < Ng < 15g: the oil passage connecting the lower oil chamber of the hydraulic synchronizer and the oil passage connecting the synchronous oil release valve in the first plate ball valve are opened, and the oil passage connecting the rod chamber of the support cylinder and the oil passage connecting the gear pump in the second plate ball valve are opened, so that the hydraulic oil in the rodless chamber of the support cylinder flows to the upper oil chamber of the hydraulic synchronizer, and the hydraulic oil in the lower oil chamber of the hydraulic synchronizer flows to the synchronous oil release valve through the first plate ball valve and flows back to the hydraulic oil tank, thereby causing the piston rod of the support cylinder to descend;

[0028] When the device is subjected to a slope angle dynamic adjustment test under a hypergravity environment of Ng≥15g: the oil passage hole in the first plate ball valve connected to the lower oil chamber of the hydraulic synchronizer and the oil passage hole connected to the synchronous oil release valve are opened, and the oil passage hole in the second plate ball valve connected to the rod chamber of the support cylinder and the oil passage hole connected to the hydraulic oil tank are opened, so that the hydraulic oil in the rodless chamber of the support cylinder flows to the upper oil chamber of the hydraulic synchronizer, and the hydraulic oil in the lower oil chamber of the hydraulic synchronizer flows to the synchronous oil release valve through the first plate ball valve and flows back to the hydraulic oil tank, thereby causing the piston rod of the support cylinder to descend;

[0029] When the device is reset under normal gravity: the oil passage hole in the first plate ball valve connected to the hydraulic synchronizer and the oil passage hole connected to the gear pump are opened, and the oil passage hole in the second plate ball valve connected to the support cylinder and the oil passage hole connected to the hydraulic oil tank are opened, so that the hydraulic oil enters the lower oil chamber of the hydraulic synchronizer through the gear pump and the first plate ball valve. The hydraulic oil in the upper oil chamber of the hydraulic synchronizer flows back to the rodless chamber of the three support cylinders, and the piston rod of the support cylinder is lifted upward, thereby realizing the angle reset of the unstable model box and the stacking model box.

[0030] The hydraulic principle of the angle adjustment system is as follows:

[0031] The tilt angle adjustment of the unstable model box under hypergravity is controlled by draining oil through a synchronous drain valve. During design and manufacturing, the cross-sectional areas of the three support cylinders and the three hydraulic chambers of the hydraulic synchronizer are equal, controlling the synchronous descent of the three support cylinders. This achieves mechanically forced synchronous descent of the support cylinders, eliminating the need for servo valves and proportional valves, ensuring structural reliability under hypergravity acceleration values ​​(Ng). The angle adjustment system not only achieves synchronization of the three support cylinders but also eliminates the need for a power source during oil draining; the oil can be drained using the device's own gravity under hypergravity conditions. The support cylinder remains vertically positioned throughout the angle change of the unstable model box, mitigating the effects of hypergravity. The weight of the model box under hypergravity is treated as the load on the support cylinder, increasing the internal pressure of the hydraulic system. As the hypergravity g-value increases, the system oil pressure rises, making the adjustment of the support cylinder's descent to change the tilt angle of the unstable model box more effective and simpler under hypergravity. Furthermore, there is no piston rod deformation due to its own weight, and no crawling or jamming phenomena, avoiding the generation of excessive eccentric friction on the piston, which would affect the stability of the device.

[0032] The entire angle adjustment system is reliable in structure, with precise control of valve opening and controllable descent speed of the support cylinders. The angle adjustment system can be energized and de-energized by combining the opening and closing of various manual plate ball valves with a one-way oil pump, facilitating experiments. The angle adjustment system adopts a fully enclosed oil supply and drainage method, ensuring that the oil does not come into contact with air, thus maintaining its elastic modulus and preventing the presence of gas in the support cylinders. This, in turn, ensures the synchronized movement of the three support cylinders during the experiment.

[0033] The support cylinder has two oil passages: a rodless chamber and a rod chamber. The hydraulic synchronizer has six independent oil chambers divided by three pistons, each with an equal cross-section. The plate ball valve is a two-position three-way valve, allowing manual selection of two of the three oil passages. The synchronized drain valve, driven by a motor reducer, moves the valve core, thereby changing the oil passage cross-section of the valve core and adjusting the hydraulic oil flow in the drain line of the angle adjustment system. This, in turn, changes the drain speed of the three lower chambers of the hydraulic synchronizer, further altering the inlet speed of the three independent upper chambers, and thus precisely controlling the descent speed of the three support cylinders.

[0034] When the device operates under centrifugal force in a low hypergravity acceleration (Ng) environment: the second plate ball valve connects the rod chambers of the three support cylinders to the high-pressure hydraulic oil outlet of the gear pump, while the first plate ball valve connects the three independent lower chambers of the hydraulic synchronizer to the hydraulic oil inlet of the synchronous drain valve. Because the piston rod of the support cylinder is loaded with the stacking model box, the upper part of the rod chamber of the support cylinder, along with the pressurized hydraulic oil supplied by the support cylinder reset hydraulic pump, generates back pressure in the rodless chamber of the support cylinder. This causes the hydraulic oil in the rodless chamber of the support cylinder to flow to the three independent upper chambers of the hydraulic synchronizer. The hydraulic oil in the three independent lower chambers of the hydraulic synchronizer flows through the first plate ball valve to the inlet of the synchronous drain valve. The flow rate of the hydraulic oil is controlled by the synchronous drain valve, and the oil ultimately returns to the hydraulic oil tank. This, in turn, controls the descent speed of the support cylinder, i.e., the rate of change of the tilt angle of the unstable model box, ultimately resulting in a decrease in the height of the stacking model box and an increase in the angle of the unstable model box.

[0035] When the device operates under centrifugal force in an environment with a hypergravity acceleration of Ng: the second plate ball valve connects the rod chambers of the three support cylinders to the hydraulic lines of the hydraulic tank, while the first plate ball valve connects the three independent lower chambers of the hydraulic synchronizer to the hydraulic oil inlet of the synchronous drain valve. Because the piston rod of the support cylinder is loaded with the stacking model box, the rodless chamber of the support cylinder experiences back pressure, causing the hydraulic oil in the rodless chamber to flow to the three independent upper chambers of the hydraulic synchronizer. The hydraulic oil in the three independent lower chambers of the hydraulic synchronizer flows through the first plate ball valve to the inlet of the synchronous drain valve. The flow rate of the hydraulic oil is controlled by the synchronous drain valve, and the oil ultimately returns to the hydraulic tank. This controls the descent speed of the support cylinders, ultimately resulting in a decrease in the height of the stacking model box and an increase in the angle of the unstable model box.

[0036] During the normal gravity environment reset operation: the second plate ball valve connects the hydraulic lines between the rod chambers of the three support cylinders and the hydraulic oil tank, while the first plate ball valve connects the three independent lower chambers of the hydraulic synchronizer to the high-pressure hydraulic oil outlet of the gear pump. Hydraulic oil flows through the high-pressure hydraulic oil outlet of the gear pump and the first plate ball valve into the three independent lower chambers of the hydraulic synchronizer. The hydraulic oil in these chambers pushes the synchronizer piston upwards, while the hydraulic oil in the three independent upper chambers of the synchronizer flows back to the lower chambers of the three support cylinders. The piston rods of the support cylinders rise upwards, ultimately increasing the height of the stacking model box and resetting the angle of the unstable model box.

[0037] The device of this invention utilizes a seesaw principle to design the angle change of the unstable model box. The rotation fulcrum of the unstable model box is located behind its own center of mass, and the front of the unstable model box rests on the upper surface of the stacking model box. The unstable model box can rotate solely by its own weight, while exerting minimal pressure on the stacking model box. The stacking model box is supported by three hydraulic cylinders and has three guide pillars to ensure its structural stability. The initial angle of the unstable model box can be adjusted by raising and lowering the model box support system, and the slope inclination can be dynamically adjusted by mechanically and synchronously lowering the stacking model box using the three hydraulic cylinders.

[0038] This invention's device is suitable for hypergravity environments. Three vertically placed support cylinders mitigate the effects of hypergravity, eliminating bending moments and treating the weight of the model box under hypergravity as a load. This increases the internal pressure of the hydraulic system; as the hypergravity g-value increases, the system oil pressure rises, effectively resisting hypergravity. Furthermore, geometric decoupling and mechanically forced synchronous descent of the three cylinders change the slope angle, ensuring the device's stability. This invention operates under hypergravity conditions of 150g full load and 300g unload. It allows adjustment of different device tilt angles and application of various external influencing factors to study slope model instability failure modes, tailings dam seismic performance, loose saturated sand shear characteristics, and landslide sliding processes along the sliding bed. This experimental device helps researchers simulate natural or engineering slope disaster processes in the laboratory, contributing to the understanding of the instability-sliding dynamic transformation mechanism during high slope instability and disaster, and providing theoretical support and technical verification for the prediction, evaluation, and control of large-scale slope disasters.

[0039] The beneficial effects of this invention are:

[0040] 1. The device of this invention can be used to study the failure mechanism of slopes under different slope angles under hypergravity, the influence of different slope angle change rates on slope liquefaction instability, and the shear characteristics of saturated sand. It provides a reliable basis for engineering design, slope reinforcement schemes and early warning system optimization, deepens the understanding of soil particle physical and mechanical properties and the instability law of slopes under prototype sites, and improves the safety and reliability of slope engineering design.

[0041] 2. In the device of this invention, the hydraulic support cylinder and the hydraulic synchronizer are arranged vertically, which weakens the influence of hypergravity. The weight of the model box under hypergravity is used as the load of the support cylinder, which increases the internal pressure of the hydraulic system. As the hypergravity g value increases, the system oil pressure is higher, and the control angle performance is optimized and stable and reliable. At the same time, under high hypergravity, the piston can avoid being subjected to off-center load friction, and a guide column is provided to resist impact. It is suitable for high hypergravity conditions up to 300g.

[0042] 3. This invention combines manual adjustment under normal gravity with adjustment by a hypergravity control system. The angle of the unstable chute can be adjusted from 0 to 30°, with a large adjustment range and stable and controllable tilt rate. The device of this invention has a simple and reliable structure and can achieve dynamic adjustment of the slope angle under hypergravity by relying on its own weight without the aid of an external oil source.

[0043] 4. The device of this invention can realistically reproduce the stress conditions of the original slope and accurately reproduce the instability and failure process. The test at the model scale has good repeatability and can reproduce the process of slope instability, sliding and deceleration accumulation. This invention is used to simulate the natural or engineering slope disaster process, to reveal the dynamic transformation mechanism of instability-sliding in the process of high slope instability and failure disaster, and to provide theoretical support and technical verification for the prediction, evaluation and control of large slope disasters. Attached Figure Description

[0044] Figure 1 is a schematic diagram of the dynamic slope angle adjustment device of the present invention;

[0045] Figure 2 is a schematic diagram of the angle adjustment system;

[0046] Figure 3 is a schematic diagram of the hydraulic synchronization principle in the angle adjustment system;

[0047] Figure 4 is a schematic diagram of the hydraulic system during centrifugal operation of the device;

[0048] Figure 5 is a schematic diagram of the hydraulic system during device shutdown and reset.

[0049] Figure 6 is a schematic diagram of the model box support system;

[0050] Figure 7 is a schematic diagram of the unstable model box;

[0051] Figure 8 is a schematic diagram of the stacking model box;

[0052] Figure 9 is a schematic diagram of angle adjustment according to an embodiment of the present invention;

[0053] Figure 10 is a three-dimensional view of the overall device of the present invention.

[0054] In the diagram: 1. Instability model box; 2. Stacking model box; 3. Model box support system; 4. Angle adjustment system; 1.1-Rear baffle; 1.2-First observation window; 1.3-First model box bottom plate; 1.4-First model box side plate; 1.6-Upper connecting plate; 1.7-Transition plate; 1.8-Transition plate rotation axis; 2.2-Second observation window; 2.3-Second model box bottom plate; 2.4-Second model box side plate; 2.6-Front baffle; 3.1-Rotating shaft; 3.2- 3.3 Bearing housing; 3.4 Top plate; 3.5 Guide column assembly; 3.6 Height adjusting screw assembly; 3.7 Hydraulic oil tank; 4.1 Guide column assembly; 4.2 Support cylinder; 4.3 Cylinder clamp assembly; 5.1 Synchronous drain valve; 5.2 Hydraulic synchronizer; 6.2 Pressure sensor; 6.3 First plate ball valve; 6.4 Second plate ball valve; 6.5 Gear pump; 6.6 Motor; 6.7 Relief valve; 6.8 Support cylinder reset hydraulic pump. Detailed Implementation

[0055] The present invention will be described in detail below with reference to specific implementation examples. These examples will help those skilled in the art to further understand the present invention, but do not limit the present invention in any way.

[0056] As shown in Figure 1, the device includes an unstable model box 1, a stacked model box 2, a model box support system 3, and an angle adjustment system 4. The bottom ends of the model box support system 3 and the angle adjustment system 4 are fixedly connected to an external hoisting base plate, which is placed in the basket of the centrifuge. The unstable model box 1 is used to place the soil model. The bottom end of the unstable model box 1 is hinged to the top end of the model box support system 3, which can swing up and down. The stacked model box 2 is installed on the angle adjustment system 4, which can move up and down. The unstable model box 1 is attached to the stacked model box 2. The angle adjustment system 4 is connected to an external control system.

[0057] Both the unstable model box 1 and the stacking model box 2 have openings. The opening of the unstable model box 1 is used as the front direction of the device, and the opening of the stacking model box 2 is located in the rear direction of the device. The opening of the unstable model box 1 is placed on the upper surface of the opening of the stacking model box 2. The angle adjustment system 4 is used to control the up and down movement of the stacking model box 2. When the stacking model box 2 moves up and down, the front of the unstable model box 1 moves up and down synchronously with the stacking model box 2, thereby changing the tilt angle of the unstable model box 1.

[0058] As shown in Figure 2, the angle adjustment system 4 includes three retractable guide column assemblies 4.1, three support cylinders 4.2, cylinder clamp assembly 4.3, synchronous oil release valve 5.1, hydraulic synchronizer 5.2, and support cylinder reset hydraulic pump 6.8;

[0059] The bottom ends of the guide column assembly 4.1 and the support cylinder 4.2 are vertically fixed to the lifting base plate. The top of the guide column assembly 4.1 and the support cylinder 4.2 housing are connected by the cylinder clamp assembly 4.3. The guide column assembly 4.1 and the support cylinder 4.2 are arranged alternately, as shown in Figure 3. The rodless chambers of the three support cylinders 4.2 are respectively connected to the upper chambers of the three independent chambers of the hydraulic synchronizer 5.2. The lower chambers of the three independent chambers of the hydraulic synchronizer 5.2 are all connected through the first plate ball valve 6.3 and the synchronous oil release valve 5.1. The rod chambers of the three support cylinders 4.2 are all connected to the support cylinder reset hydraulic pump 6.8. The outlet of the synchronous oil release valve 5.1 and the support cylinder reset hydraulic pump 6.8 are both connected to the hydraulic oil tank 3.6 in the model box support system 3.

[0060] The top ends of the guide column assembly 4.1 and the support cylinder 4.2 are both fixedly connected to the bottom end of the stacking model box base plate 2.3 in the stacking model box 2. The angle adjustment system 4 is used to precisely control the lifting and lowering of the stacking model box 2 through the telescopic support cylinder 4.2, thereby precisely controlling the angle change value and angle change rate of the unstable model box 1 overlapping on the stacking model box 2 in a hypergravity environment. The support cylinder 4.2 is also used to support the weight of the unstable model box 1 and the stacking model box 2.

[0061] As shown in Figure 4, the hydraulic pump 6.8 for resetting the support cylinders includes a second plate ball valve 6.4, a gear pump 6.5, a motor 6.6, and a relief valve 6.7. The motor 6.6 and relief valve 6.7 are both connected to the gear pump 6.5. The second plate ball valve 6.4 has three oil passages. The first oil passage of the second plate ball valve 6.4 is connected to the independent rod chamber of the three support cylinders 4.2. The second oil passage of the second plate ball valve 6.4 is connected to the high-pressure hydraulic oil outlet of the gear pump 6.5. The third oil passage of the second plate ball valve 6.4 is connected to the model box. The hydraulic oil tank 3.6 in the support system 3 is connected; the first plate ball valve 6.3 is provided with three oil passages. The first oil passage of the first plate ball valve 6.3 is connected to the lower oil chamber of the three independent oil chambers of the hydraulic synchronizer 5.2. The second oil passage of the first plate ball valve 6.3 is connected to the high-pressure hydraulic oil outlet of the gear pump 6.5. The third oil passage of the first plate ball valve 6.3 is connected to the inlet of the synchronous drain valve 5.1. The hydraulic inlet and outlet of the gear pump 6.5 and the relief valve 6.7 are all connected to the hydraulic oil tank 3.6 in the model box support system 3.

[0062] Both the guide column assembly 4.1 and the support cylinder 4.2 are vertically mounted on the hoisting base plate. The guide column assembly 4.1 ensures the verticality of the stacked model box 2 during lifting and can withstand a certain horizontal impact load when the test soil model fails and falls. The angle adjustment system 4 mainly changes the initial angle of the unstable model box 1 by changing the height of the center of gravity of the stacked model box 2, thereby achieving the angle adjustment of the unstable model box 1. The angle adjustment of the unstable model box 1 is automatic under hypergravity, with an angle change range of 0~15° and a controllable angle adjustment speed. The angle adjustment system 4 is mainly used for angle adjustment under hypergravity. In a specific embodiment, hypergravity specifically refers to hypergravity with an acceleration value greater than 15g.

[0063] Pressure sensors 6.2 can be installed on the pipes connecting the support cylinder 4.2 and the hydraulic synchronizer 5.2, the pipes connecting the hydraulic synchronizer 5.2 and the first plate ball valve 6.3, and the pipes connecting the first plate ball valve 6.3 and the gear pump 6.5. The hydraulic oil tank 3.6 in the model box support system 3 is responsible for storing the oil needed for the hydraulic synchronizer 5.2 to fill and drain. The support cylinder reset hydraulic pump 6.8, through the first plate ball valve 6.3, connects to the lower oil chamber of the three independent oil chambers of the hydraulic synchronizer 5.2. When the piston of the hydraulic synchronizer 5.2 pushes upward, it pushes the oil from the upper chambers of the three independent oil chambers back to the three support cylinders 4.2, controlling the piston rods of the three support cylinders 4.2 to rise, thus resetting the device.

[0064] As shown in Figure 6, the model box support system 3 includes a rotating shaft 3.1, a bearing seat 3.2, an upper top plate 3.3, a guide column assembly 3.4, a height adjustment screw assembly 3.5, and a hydraulic oil tank 3.6;

[0065] The bottom of the hydraulic oil tank 3.6 is fixedly connected to the hoisting base plate. The bottoms of the telescopic guide column assembly 3.4 and the telescopic height adjusting screw assembly 3.5 are both fixedly connected to the hydraulic oil tank 3.6. The tops of the guide column assembly 3.4 and the height adjusting screw assembly 3.5 are both fixedly connected to the lower surface of the upper top plate 3.3. The height adjusting screw assembly 3.5 is located between the two guide column assemblies 3.4. The bearing seat 3.2 is fixedly installed on the upper top plate 3.3. The rotating shaft 3.1 is rotatably installed on the bearing seat 3.2 around its own axis. The first model box bottom plate 1.3 of the unstable model box 1 is hinged to the rotating shaft 3.1 of the model box support system 3 so that the unstable model box 1 can swing up and down relative to the model box support system 3.

[0066] The model box support system 3 is mainly used to manually adjust and change the height of the support point of the unstable model box 1, thereby changing the tilt angle of the unstable model box 1. The angle change range is 0~15°. Under superimposed hypergravity, the angle adjustment range is 0~15°, and the total angle adjustment range is 0-30°.

[0067] As shown in Figure 7, the unstable model box 1 includes a rear baffle 1.1, a first observation window 1.2, a first model box bottom plate 1.3, two first model box side plates 1.4, an upper connecting plate 1.6, a transition plate 1.7, and a transition plate rotation shaft 1.8. The bottom ends of the rear baffle 1.1 and the two first model box side plates 1.4 are fixedly connected to the first model box bottom plate 1.3. The two first model box side plates 1.4 are arranged symmetrically relative to each other, and the left and right ends of the rear baffle 1.1 are respectively connected to the two first model box side plates 1. 4. The front top of the two first model box side plates 1.4 are connected by an upper connecting plate 1.6. The front end of the first model box bottom plate 1.3 is hinged to the transition plate 1.7 through the transition plate rotation shaft 1.8. The soil model is placed on the first model box bottom plate 1.3. The middle of the first model box side plate 1.4 is provided with a first observation window 1.2 for observing the soil model. The transition plate 1.7 of the unstable model box 1 overlaps at the opening of the stacking model box 2, which facilitates the destruction of the soil model and its entry into the stacking model box 2.

[0068] The first model box bottom plate 1.3 has a groove in the middle. The first model box bottom plate 1.3 is hinged to the rotating shaft 3.1 of the model box support system 3 at the groove. The groove of the first model box bottom plate 1.3 is parallel to the axis of the rotating shaft 3.1.

[0069] The unstable model box 1 is used to stack soil models in simulation tests. The front of the unstable model box 1 overlaps the upper surface of the second model box bottom plate 2.3 of the stacking model box 2. The angle of the unstable model box 1 can be adjusted by the angle adjustment system 4, thereby changing the angle of the soil model. The rear baffle 1.1 is installed at the rear end of the unstable model box 1. The front end of the unstable model box 1 may not be equipped with any baffle to form an opening in the unstable model box 1, allowing the soil model to fall from the opening of the unstable model box 1 into the stacking model box 2.

[0070] As shown in Figure 8, the stacking model box 2 includes a second observation window 2.2, a second model box bottom plate 2.3, two second model box side plates 2.4, and a front baffle 2.6; the bottom ends of the front baffle 2.6 and the two second model box side plates 2.4 are all fixedly connected to the second model box bottom plate 2.3. The two second model box side plates 2.4 are arranged symmetrically relative to each other, and the left and right ends of the front baffle 2.6 are respectively connected to the two second model box side plates 2.4. A second observation window 2.2 for observing the soil model is provided in the middle of the second model box side plate 2.4.

[0071] The transition plate 1.7 of the unstable model box 1 overlaps the bottom plate 2.3 of the second model box. The guide column assembly 4.1 and the support cylinder 4.2 in the angle adjustment system 4 are both fixedly connected to the lower surface of the bottom plate 2.3 of the second model box. The angle adjustment system 4 is used to adjust the height of the stacked model box 2, thereby changing the tilt angle of the unstable model box 1 that overlaps the stacked model box 2.

[0072] Specifically, the stacking model box 2 is used to stack the soil impacted from the unstable model box 1 in the slope instability and sliding test, and can move up and down with the action of the angle adjustment system 4, thereby changing the tilt angle of the unstable model box 1 that is attached to the upper surface of the stacking model box 2.

[0073] An instability model box 1 in the angle adjustment system 4 is equipped with an inclination sensor, a pressure sensor 6.2 is installed on the support cylinder 4.2, and a valve core displacement sensor is installed on the synchronous oil release valve 5.1. The support cylinder 4.2, inclination sensor, pressure sensor 6.2, valve core displacement sensor and motor 6.6 in the support cylinder reset hydraulic pump 6.8 in the angle adjustment system 4 are connected to an external control system.

[0074] The embodiments of the present invention include the following steps:

[0075] Step S1, Model Making: Place the soil model inside the unstable model box 1. After the soil model is made, install the unstable model box 1 on the model box support system 3.

[0076] Step S2: Hoist the device into the basket of the geotechnical centrifuge, and connect the tilt sensor, pressure sensor 6.2, and valve core displacement sensor inside the device to the external control system to conduct a dynamic slope adjustment test under hypergravity environment, as shown in Figure 9.

[0077] Step S3: In the slope angle dynamic adjustment test, the soil models in the instability model box 1 and the accumulation model box 2 are observed to obtain the failure performance of the soil models under different slopes, so as to restore the failure performance of the prototype soil sample under different slopes under real working conditions.

[0078] Step S2 is as follows:

[0079] As shown in Figure 10, firstly, the hoisting base plate equipped with the test device is hoisted into the centrifuge and fixed. Under constant gravity, the external control system controls two of the three oil passages in the first plate ball valve 6.3 and the second plate ball valve 6.4 to be open, and the centrifuge is started. The centrifugal acceleration of the centrifuge is gradually increased to the preset Ng and maintained for the preset time. By controlling the oil discharge speed of the synchronous oil discharge valve 5.1, the piston rod of the support cylinder 4.2 moves up and down precisely at the preset speed. The piston rod of the support cylinder 4.2 drives the stacking model box 2 to move up and down synchronously, thereby changing the tilt angle of the unstable model box 1 and the soil model. Then, the destructive performance of the soil model is observed at different tilt angles.

[0080] In step S2, the specific method by which two of the three oil passages in the first plate ball valve 6.3 and the second plate ball valve 6.4 are controlled to be open, so that the piston rod of the supporting cylinder 4.2 moves up and down, is as follows:

[0081] As shown in Figure 4, when the device undergoes a slope angle dynamic adjustment test under hypergravity conditions where g < Ng < 15g: the oil passages in the first plate ball valve 6.3, which connect to the lower oil chambers of the three independent oil chambers of the hydraulic synchronizer 5.2, and the oil passages connected to the synchronous drain valve 5.1, are opened; the oil passages in the second plate ball valve 6.4, which connect to the independent rod chambers of the three support cylinders 4.2, and the oil passages connected to the gear pump 6.5, are opened, causing the hydraulic oil in the rodless chamber of the support cylinder 4.2 to flow to the upper oil chamber of the hydraulic synchronizer 5.2, and the hydraulic oil in the lower oil chamber of the hydraulic synchronizer 5.2 to flow through the first plate ball valve 6.3 to the synchronous drain valve 5.1 and back to the hydraulic oil tank 3.6, thereby causing the piston rod of the support cylinder 4.2 to descend; where g represents the acceleration due to normal gravity; N represents the ratio of centrifugal acceleration to gravitational acceleration under hypergravity conditions;

[0082] When the device undergoes a slope angle dynamic adjustment test under hypergravity conditions of Ng≥15g: the oil passages in the first plate ball valve 6.3 connected to the lower oil chambers of the three independent oil chambers of the hydraulic synchronizer 5.2 and the oil passages connected to the synchronous drain valve 5.1 are opened; the oil passages in the second plate ball valve 6.4 connected to the independent rod chambers of the three support cylinders 4.2 and the oil passages connected to the hydraulic oil tank 3.6 are opened, so that the hydraulic oil in the rodless chamber of the support cylinder 4.2 flows to the upper oil chamber of the hydraulic synchronizer 5.2, and the hydraulic oil in the lower oil chamber of the hydraulic synchronizer 5.2 flows through the first plate ball valve 6.3 to the synchronous drain valve 5.1 and back to the hydraulic oil tank 3.6, thereby causing the piston rod of the support cylinder 4.2 to descend;

[0083] As shown in Figure 5, when the device is reset under normal gravity: the oil passage connecting the lower oil chamber of the three independent oil chambers of the hydraulic synchronizer 5.2 in the first plate ball valve 6.3 and the oil passage connecting the gear pump 6.5 are opened; the oil passage connecting the independent rod chamber of the three support cylinders 4.2 in the second plate ball valve 6.4 and the oil passage connecting the hydraulic oil tank 3.6 are opened, so that the hydraulic oil enters the lower oil chamber of the hydraulic synchronizer 5.2 from the gear pump 6.5 through the first plate ball valve 6.3, and the hydraulic oil in the upper oil chamber of the hydraulic synchronizer 5.2 flows back to the rodless chamber of the three support cylinders 4.2. The piston rod of the support cylinder 4.2 is lifted upward, thereby realizing the angle reset of the unstable model box 1 and the stacked model box 2.

[0084] Specifically, the descent speed of the piston rod of the support cylinder 4.2 is precisely controlled by the oil discharge speed of the synchronous oil discharge valve 5.1. If the entire test apparatus is tested in a low-g environment with a centrifugal force below 15g, the load on the support cylinder 4.2 generated by the centrifugal force is small, and the hydraulic pressure in the rodless chamber of the support cylinder is low, which is not conducive to the oil discharge control of the synchronous oil discharge valve 5.1. Therefore, in the low-g test, it is considered to connect the gear pump 6.5 to pressurize the upper chamber of the support cylinder, increase the load on the support cylinder 4.2, and thus increase the hydraulic system pressure of the oil discharge circuit of the synchronous oil discharge valve 5.1, so as to facilitate the oil discharge of the synchronous oil discharge valve 5.1. If the entire test apparatus is tested in a high-g environment, the load on the support cylinder generated by the centrifugal force is large, and the hydraulic pressure in the rodless chamber of the support cylinder is large. Therefore, it is not necessary to connect the gear pump 6.5. The rod chamber of the support cylinder 4.1 can be directly connected to the hydraulic oil tank 3.6 through the second plate ball valve 6.4.

[0085] The core function of this device is the angle adjustment of the unstable model box 1. The first 15° is manually adjustable, and the subsequent 15° is controlled in real-time by the angle adjustment system 4. The adjustable angle of the unstable model box 1 within the 0-15° range is achieved by manually adjusting the height of the model box support system 3. This adjustment is done by manually rotating the nut sleeve to change the height adjustment screw assembly 3.5, thereby adjusting the extension and retraction of the stud, which in turn adjusts the height of the model box support system 3, and thus changes the initial angle of the unstable model box 1. During the experiment, the subsequent 15° adjustment after the centrifuge test is started is mainly achieved by the action of the three synchronous support cylinders 4.2 at the bottom of the stacked model box 2. As the piston rods of the three synchronous support cylinders 4.2 descend, the front end of the unstable model box 1 descends synchronously, further changing the angle of the unstable model box 1. The tilt angle of the unstable model box 1 is used to control the tilt angle of the soil model, simulating the slope of the prototype soil sample.

[0086] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A dynamic slope angle adjustment test device suitable for high-gravity environments, characterized in that: It includes an unstable model box (1), a stacked model box (2), a model box support system (3), and an angle adjustment system (4); the bottom ends of the model box support system (3) and the angle adjustment system (4) are fixedly connected to an external hoisting base plate, which is placed in the basket of the centrifuge. The unstable model box (1) is used to place the soil model. The bottom end of the unstable model box (1) can be hinged to the top of the model box support system (3) by swinging up and down. The stacked model box (2) can be installed on the angle adjustment system (4) by moving up and down. The unstable model box (1) is attached to the stacked model box (2). The angle adjustment system (4) is connected to an external control system.

2. The slope angle dynamic adjustment test device suitable for high-gravity conditions according to claim 1, characterized in that: The angle adjustment system (4) includes three guide column assemblies (4.1), three support cylinders (4.2), cylinder clamp assembly (4.3), synchronous oil release valve (5.1), hydraulic synchronizer (5.2), and support cylinder reset hydraulic pump (6.8). The bottom ends of the guide column assembly (4.1) and the support cylinder (4.2) are vertically fixed to the hoisting base plate. The tops of the guide column assembly (4.1) and the support cylinder (4.2) are connected by the cylinder clamp assembly (4.3). The rodless chambers of the three support cylinders (4.2) are respectively connected to the upper chambers of the three independent chambers of the hydraulic synchronizer (5.2). The lower chambers of the three independent chambers of the hydraulic synchronizer (5.2) are all connected by the first plate ball valve (6.3) and the synchronous oil release valve (5.1). The rod chambers of the three support cylinders (4.2) are all connected to the support cylinder reset hydraulic pump (6.8). The synchronous oil release valve (5.1) and the support cylinder reset hydraulic pump (6.8) are both connected to the hydraulic oil tank (3.6) in the model box support system (3). The top ends of the guide column assembly (4.1) and the support cylinder (4.2) are fixedly connected to the bottom end of the stacking model box (2). The angle adjustment system (4) is used to control the lifting and lowering of the stacking model box (2) through the telescopic support cylinder (4.2), thereby controlling the angle change value and angle change rate of the unstable model box (1) attached to the stacking model box (2) in the hypergravity environment.

3. The slope angle dynamic adjustment test device suitable for high-gravity conditions according to claim 2, characterized in that: The hydraulic pump (6.8) for resetting the supporting cylinders includes a second plate ball valve (6.4), a gear pump (6.5), a motor (6.6), and a relief valve (6.7). The motor (6.6) and relief valve (6.7) are both connected to the gear pump (6.5). The second plate ball valve (6.4) has three oil passages. The first oil passage of the second plate ball valve (6.4) is connected to the independent rod chamber of the three supporting cylinders (4.2). The second oil passage of the second plate ball valve (6.4) is connected to the hydraulic oil outlet of the gear pump (6.5). The third oil passage of the second plate ball valve (6.4) is connected to... The hydraulic oil tank (3.6) in the model box support system (3) is connected; the first plate ball valve (6.3) is provided with three oil passages. The first oil passage of the first plate ball valve (6.3) is connected to the lower oil chamber of the three independent oil chambers of the hydraulic synchronizer (5.2). The second oil passage of the first plate ball valve (6.3) is connected to the hydraulic oil outlet of the gear pump (6.5). The third oil passage of the first plate ball valve (6.3) is connected to the inlet of the synchronous drain valve (5.1). The gear pump (6.5) and the overflow valve (6.7) are both connected to the hydraulic oil tank (3.6) in the model box support system (3).

4. The slope angle dynamic adjustment test device suitable for high hypergravity as described in claim 1, characterized in that: The model box support system (3) includes a rotating shaft (3.1), a bearing seat (3.2), an upper top plate (3.3), a guide column assembly (3.4), a height adjustment screw assembly (3.5), and a hydraulic oil tank (3.6). The bottom end of the hydraulic oil tank (3.6) is fixedly connected to the hoisting base plate. The bottom ends of the telescopic guide column assembly (3.4) and the height adjustment screw assembly (3.5) are both fixedly connected to the hydraulic oil tank (3.6). The top ends of the guide column assembly (3.4) and the height adjustment screw assembly (3.5) are both fixedly connected to the lower surface of the upper top plate (3.3). The bearing seat (3.2) is fixedly installed on the upper top plate (3.3). The rotating shaft (3.1) is rotatably installed on the bearing seat (3.2) around its own axis. The first model box bottom plate (1.3) of the unstable model box (1) is hinged to the rotating shaft (3.1) of the model box support system (3).

5. The slope angle dynamic adjustment test device suitable for high-gravity conditions according to claim 1, characterized in that: The unstable model box (1) includes a rear baffle (1.1), a first observation window (1.2), a first model box bottom plate (1.3), two first model box side plates (1.4), an upper connecting plate (1.6), a transition plate (1.7), and a transition plate rotation shaft (1.8). The bottom ends of the rear baffle (1.1) and the two first model box side plates (1.4) are fixedly connected to the first model box bottom plate (1.3). The two first model box side plates (1.4) are arranged symmetrically, and the two ends of the rear baffle (1.1) are respectively connected to the two first model box side plates (1.4). The top front parts of the two first model box side plates (1.4) are connected by an upper connecting plate (1.6). The front end of the first model box bottom plate (1.3) is connected by a transition plate rotating shaft (1.8). The soil model is hinged to the transition plate (1.7) and placed on the bottom plate (1.3) of the first model box. The middle part of the side plate (1.4) of the first model box is provided with a first observation window (1.2) for observing the soil model. The transition plate (1.7) of the unstable model box (1) overlaps at the opening of the stacked model box (2). The middle part of the bottom plate (1.3) of the first model box is provided with a groove. The bottom plate (1.3) of the first model box is hinged to the rotating shaft (3.1) of the model box support system (3) at the groove.

6. The slope angle dynamic adjustment test device suitable for high hypergravity as described in claim 1, characterized in that: The stacking model box (2) includes a second observation window (2.2), a second model box bottom plate (2.3), two second model box side plates (2.4), and a front baffle (2.6); the bottom ends of the front baffle (2.6) and the two second model box side plates (2.4) are fixedly connected to the second model box bottom plate (2.3), the two second model box side plates (2.4) are arranged symmetrically, and the two ends of the front baffle (2.6) are respectively connected to the two second model box side plates (2.4), and a second observation window (2.2) for observing the soil model is provided in the middle of the second model box side plate (2.4). The transition plate (1.7) of the unstable model box (1) overlaps the bottom plate (2.3) of the second model box. The guide column assembly (4.1) and the support cylinder (4.2) in the angle adjustment system (4) are both fixedly connected to the lower surface of the bottom plate (2.3) of the second model box. The angle adjustment system (4) is used to adjust the height of the stacked model box (2), thereby changing the tilt angle of the unstable model box (1) overlapping the stacked model box (2).

7. The slope angle dynamic adjustment test device suitable for high hypergravity as described in claim 2, characterized in that: The instability model box (1) in the angle adjustment system (4) is equipped with an inclination sensor. The inclination sensor and the hydraulic pump (6.8) for resetting the support cylinder are both externally connected to the control system.

8. A test method for dynamic adjustment of slope angle under high gravity, applicable to the device described in any one of claims 1-7, characterized in that, Includes the following steps: Step S1, Model making: Place the soil model inside the unstable model box (1). After the soil model is made, install the unstable model box (1) on the model box support system (3). Step S2: Hoist the device into the basket of the geotechnical centrifuge to conduct a dynamic slope adjustment test under hypergravity conditions; Step S3: In the slope angle dynamic adjustment test, the soil model in the unstable model box (1) is observed to obtain the failure performance of the soil model under different slopes, and then the failure performance of the prototype soil sample under different slopes under real working conditions is restored.

9. The method for dynamic adjustment of slope angle suitable for high-gravity environments according to claim 8, characterized in that: The specific steps of S2 are as follows: First, the hoisting base plate with the test device installed is hoisted into the centrifuge and fixed. Under constant gravity, two of the three oil passages in the first plate ball valve (6.3) and the second plate ball valve (6.4) are controlled to be open. The centrifuge is started and the centrifugal acceleration of the centrifuge is gradually increased to the preset Ng and maintained for the preset time. At the same time, the oil discharge speed of the synchronous oil discharge valve (5.1) is controlled so that the piston rod of the support cylinder (4.2) moves up and down. The piston rod of the support cylinder (4.2) drives the stacking model box (2) to move up and down synchronously, thereby changing the tilt angle of the unstable model box (1) and the soil model. Then, the destructive performance of the soil model is observed at different tilt angles.

10. The method for dynamic adjustment of slope angle suitable for high-gravity environments according to claim 9, characterized in that: In step S2, the specific method by which two of the three oil passages in the first plate ball valve (6.3) and the second plate ball valve (6.4) are controlled to be open, so that the piston rod of the supporting cylinder (4.2) moves up and down, is as follows: When the device is subjected to a slope angle dynamic adjustment test under hypergravity conditions of g < Ng < 15g: the oil passage hole in the first plate ball valve (6.3) connected to the hydraulic synchronizer (5.2) and the oil passage hole connected to the synchronous drain valve (5.1) are opened, and the oil passage hole in the second plate ball valve (6.4) connected to the support cylinder (4.2) and the oil passage hole connected to the gear pump (6.5) are opened, so that the hydraulic oil in the rodless chamber of the support cylinder (4.2) flows to the upper oil chamber of the hydraulic synchronizer (5.2), and the hydraulic oil in the lower oil chamber of the hydraulic synchronizer (5.2) flows to the synchronous drain valve (5.1) through the first plate ball valve (6.3) and flows back to the hydraulic oil tank (3.6), thereby causing the piston rod of the support cylinder (4.2) to descend; When the device is subjected to a slope angle dynamic adjustment test under hypergravity conditions of Ng≥15g: the oil passage hole in the first plate ball valve (6.3) connected to the hydraulic synchronizer (5.2) and the oil passage hole connected to the synchronous drain valve (5.1) are opened, and the oil passage hole in the second plate ball valve (6.4) connected to the support cylinder (4.2) and the oil passage hole connected to the hydraulic oil tank (3.6) are opened, so that the hydraulic oil in the rodless chamber of the support cylinder (4.2) flows to the upper oil chamber of the hydraulic synchronizer (5.2), and the hydraulic oil in the lower oil chamber of the hydraulic synchronizer (5.2) flows to the synchronous drain valve (5.1) through the first plate ball valve (6.3) and flows back to the hydraulic oil tank (3.6), thereby causing the piston rod of the support cylinder (4.2) to descend; When the device is reset under normal gravity: the oil passage hole in the first plate ball valve (6.3) connected to the hydraulic synchronizer (5.2) and the oil passage hole connected to the gear pump (6.5) are opened, and the oil passage hole in the second plate ball valve (6.4) connected to the support cylinder (4.2) and the oil passage hole connected to the hydraulic oil tank (3.6) are opened, so that the hydraulic oil enters the lower oil chamber of the hydraulic synchronizer (5.2) through the gear pump (6.5) and the first plate ball valve (6.3). The hydraulic oil in the upper oil chamber of the hydraulic synchronizer (5.2) flows back to the rodless chamber of the three support cylinders (4.2). The piston rod of the support cylinder (4.2) is lifted upward, thereby realizing the angle reset of the unstable model box (1) and the stacked model box (2).

Images