A force chain visualization model device based on force luminescent particle system

Abstract

This invention relates to the field of particle mechanics research technology, and particularly to a force chain visualization model device based on a mechanoluminescent particle system. The device includes a fully transparent shearing box, a liquid crystal micro-controlled ring shearing apparatus, an upper pressure plate, a lower pressure plate, a displacement meter, and a camera module. The lower pressure plate is connected to the liquid crystal micro-controlled ring shearing apparatus. The bottom of the fully transparent shearing box is fixed to the lower pressure plate. The fully transparent shearing box is filled with mechanoluminescent particles to form a particle system. The upper surface of the particle system is flattened, and the upper pressure plate is placed on the upper surface of the particle system. The displacement meter is mounted on top of the upper pressure plate. The camera module is mounted horizontally on the fully transparent shearing box and aligned with the particle system. The liquid crystal micro-controlled ring shearing apparatus has a control display. This invention achieves real-time dynamic visualization of the contact forces and force chain distribution between particles; it overcomes the limitations of traditional technologies on particle materials, sizes, and shapes, and is applicable to multiphase and multi-scale particle systems.

Description

Technical Field

[0001] This utility model relates to the field of particle mechanics research technology, and in particular to a force chain visualization model device based on a mechanoluminescent particle system. Background Technology

[0002] Current experimental methods for studying the mechanical behavior of particulate systems mainly include traditional shear test devices (such as ring shear testers and direct shear testers) that indirectly infer interparticle forces by measuring macroscopic shear force, displacement and other parameters; X-ray / CT tomography combined with mechanical loading devices that achieve three-dimensional imaging of particulate systems using synchrotron radiation or micro-CT; coating the particle surface with pressure-sensitive materials (such as photoelastic coatings); and pressure-sensitive particle coating technology that observes stress distribution through polarized light.

[0003] However, existing experimental methods have the following drawbacks: (1) Lack of real-time visualization capability: Traditional methods cannot simultaneously capture particle motion and force distribution, making it difficult to correlate microscopic mechanical behavior with macroscopic response. (2) Intrusiveness and material limitations: Pressure-sensitive coatings or labeled particles can alter the original mechanical properties of the system (such as friction coefficient and contact stiffness). (3) Difficulty in quantifying three-dimensional force chains: Existing optical technologies are limited to two-dimensional observation, while numerical simulations (such as DEM) rely on simplified contact models, resulting in significant deviations from reality. (4) Equipment complexity and cost: High-precision synchrotron radiation or micro-CT equipment is expensive and requires professional operation, making it difficult to popularize and apply. Utility Model Content

[0004] This invention provides a force chain visualization model device based on a mechanoluminescent particle system, aiming to solve the technical problems existing in the experimental methods for the mechanical behavior of particle systems.

[0005] This utility model provides a force chain visualization model device based on a mechanoluminescent particle system, including a fully transparent shearing box, a liquid crystal micro-controlled ring shear, an upper pressure plate, a lower pressure plate, a displacement meter, and a camera module. The lower pressure plate is connected to the liquid crystal micro-controlled ring shear, and the bottom of the fully transparent shearing box is fixed on the lower pressure plate. The fully transparent shearing box is filled with mechanoluminescent particles to form a particle system, and the upper surface of the particle system is flattened. The upper pressure plate is placed on the upper surface of the particle system, and the displacement meter is installed on top of the upper pressure plate. The camera module is mounted horizontally on the fully transparent shearing box and aligned with the particle system. The liquid crystal micro-controlled ring shear is equipped with a control display.

[0006] As a further improvement of this utility model, the force chain visualization model device based on the mechanoluminescent particle system also includes a telescopic rod, the bottom of which is connected to the liquid crystal micro-controlled ring shear, and the top of which is connected to the pressure plate.

[0007] As a further improvement of this utility model, the force chain visualization model device based on the mechanoluminescent particle system also includes a support rod and a support plate. The support rod is mounted on the liquid crystal micro-controlled ring shear, and the support plate is fixed on the support rod. The support plate is located above the upper pressure plate, and the measuring end of the displacement gauge is connected to the support plate and the upper pressure plate respectively.

[0008] As a further improvement of this utility model, the fully transparent shearing box is provided with a particle slot inside, and the bottom of the upper pressure plate is provided with a pressure block. The pressure block is matched with the slot of the particle slot. After the particle slot is filled with force luminescent particles and leveled, the pressure block is placed on the upper surface of the particle system.

[0009] As a further improvement of this utility model, the force chain visualization model device based on the mechanoluminescent particle system also includes a computer, which is connected to a liquid crystal micro-controlled ring shear.

[0010] As a further improvement of this utility model, the force chain visualization model device based on the mechanoluminescent particle system also includes a weight pan for placing weights, which is connected to the bottom of the liquid crystal micro-controlled ring shear.

[0011] As a further improvement of this utility model, the camera module is a camera or a video camera.

[0012] The beneficial effects of this invention are: to realize real-time dynamic visualization of interparticle contact forces and force chain distribution; to overcome the limitations of traditional technology on particle materials, size and shape, and to be applicable to multiphase and multiscale particle systems; and to provide a low-cost and easy-to-operate experimental platform to serve geotechnical engineering and particle mechanics research. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the force chain visualization model device based on the mechanoluminescent particle system of this utility model;

[0014] Figure 2 This is a partial structural cross-sectional view of the force chain visualization model device based on the mechanoluminescent particle system of this utility model;

[0015] Figure 3 This is a cross-sectional view of the fully transparent shear box in this utility model;

[0016] Figure 4 This is a top view of the structure of the fully transparent shear box in this utility model. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments.

[0018] The purpose of this invention is to provide a non-invasive, high-precision, multi-dimensional visualization device and method for mechanical testing of particle systems. Specifically, as follows: Figures 1 to 2 As shown, the force chain visualization model device based on the mechanoluminescent particle system 8 includes a fully transparent shearing box 1, a liquid crystal micro-controlled ring shear 2, an upper pressure plate 3, a lower pressure plate 4, a displacement meter 5, and a camera module 6. The lower pressure plate 4 is connected to the liquid crystal micro-controlled ring shear 2. The bottom of the fully transparent shearing box 1 is fixed on the lower pressure plate 4. The fully transparent shearing box 1 is filled with mechanoluminescent particles to form the particle system 8. The upper surface of the particle system 8 is flattened. The upper pressure plate 3 is placed on the upper surface of the particle system 8. The displacement meter 5 is placed on the top of the upper pressure plate 3. The camera module 6 is mounted in the horizontal direction of the fully transparent shearing box 1 and aligned with the particle system 8. The liquid crystal micro-controlled ring shear 2 is equipped with a control display 15.

[0019] The upper pressure plate 3 and the lower pressure plate 4 form a space on the LCD micro-controlled ring shearer 2 for mounting the fully transparent shearing box 1. The lower pressure plate 4 is used to fix the fully transparent shearing box 1, and the upper pressure plate 3 is used to press on the upper surface of the particle system 8 of the fully transparent shearing box 1. As the particle system 8 changes during shearing, it generates vertical displacement. The displacement meter 5 is used to detect the displacement of the upper pressure plate 3. The displacement meter 5 is connected to the LCD micro-controlled ring shearer 2 and is used to detect the vertical displacement of the particle system 8. The data is transmitted to the computer 14 program in real time. The camera module 6 is used to record the changes of the particle system 8 in real time. The LCD micro-controlled ring shearer 2 is equipped with a control display 15. By touching the operation buttons on the control display 15, the LCD micro-controlled ring shearer 2 can be controlled, including setting various shearing parameters and selecting shearing modes.

[0020] The force chain visualization model device based on the mechanoluminescent particle system 8 also includes a telescopic rod 9. The bottom of the telescopic rod 9 is connected to the LCD micro-controlled ring shear 2, and the top of the telescopic rod 9 is connected to the upper pressure plate 3. The telescopic rod 9 can be finely adjusted in the vertical direction. During shearing, the upper pressure plate 3 will press down on the particle system 8 to generate displacement. The telescopic rod 9 supports the upper pressure plate 3 while guiding the downward movement of the upper pressure plate 3.

[0021] The force chain visualization model device based on the mechanoluminescent particle system 8 also includes support rods 10 and support plates 11. The support rods 10 are mounted on the LCD micro-controlled ring shearing instrument 2, and the support plates 11 are fixed on the support rods 10. The support plates 11 are located above the upper pressure plate 3. The measuring ends of the displacement gauges 5 are connected to the support plates 11 and the upper pressure plate 3 respectively. Multiple support rods 10 are vertically installed on the LCD micro-controlled ring shearing instrument 2. The top of the support rods 10 is threaded. The support plates 11 are installed on the support rods 10 and fixed by bolts 12 to form a fixed panel located above the upper pressure plate 3. Since the position of the support rods 10 is fixed, the upper pressure plate 3 will generate a vertical position during shearing as the particle system 8 moves. The two ends of the displacement gauges 5 are connected to the support plates 11 and the upper pressure plate 3 respectively, thereby measuring the displacement of the upper pressure plate 3 relative to the support rods 10.

[0022] like Figure 3 and Figure 4 As shown, the fully transparent shearing box 1 has a particle slot 7 inside, and a pressure block 13 is provided at the bottom of the upper pressure plate 3. The pressure block 13 mates with the slot 17 of the particle slot 7. After the particle slot 7 is filled with force-illuminating particles and leveled, the pressure block 13 is placed on the upper surface of the particle system 8. The particle slot 7 is located in the middle of the fully transparent shearing box 1, so that the particle system 8 inside the particle slot 7 is subjected to uniform force during shearing. After the particle system 8 is filled and leveled, the bottom plane of the pressure block 13 can fit and contact the particle system 8, applying uniform pressure to the particle system 8. The slot design of the particle slot 7 facilitates the docking of the pressure block 13 with the particle slot 7.

[0023] The fully transparent shear box 1 is made of high-strength transparent material and is a detachable shear box. The bottom of the fully transparent shear box 1 is provided with multiple fixing holes. After the bolts 12 pass through the fixing holes, they are connected to the screw holes at the corresponding positions of the lower pressure plate 4, so that the fully transparent shear box 1 can be detachably fixed on the lower pressure plate 4.

[0024] The force chain visualization model device based on the mechanoluminescent particle system 8 also includes a computer 14, which is connected to a liquid crystal micro-controlled ring shearing apparatus 2. The computer 14 comes with various experimental programs, including: shear rate (° / min), maximum test time, and unidirectional / cyclic shearing. The experimental programs on the computer 14 use existing shearing programs, which will not be elaborated here. By setting different experimental programs, the liquid crystal micro-controlled ring shearing apparatus 2 can be controlled to perform corresponding operations.

[0025] The force chain visualization model device based on the mechanoluminescent particle system 8 also includes a weight pan 16 for placing weights, which is connected to the bottom of the LCD micro-controlled ring shearing device 2. Specifically, the weight pan 16 is suspended from the bottom of the LCD micro-controlled ring shearing device 2 by a single-lever normal loading component. By adding or removing weights on the weight pan 16, a vertical load or normal stress, i.e., confining pressure, is provided to the LCD micro-controlled ring shearing device 2.

[0026] The LCD micro-controlled ring shearing device 2 can achieve unidirectional / cyclic shearing and compression composite loading through the program set by the computer 14. The control conditions include shearing rate and shearing mode. At the same time, the vertical load can be achieved through the structural design of adding or removing weights.

[0027] The camera module 6 is a camera or video camera. The LCD micro-controlled ring shearing instrument 2 can record the normal stress and vertical displacement of the particle system 8 in real time. It can be equipped with a Sony camera (Sony Alpha 7 IV, ILCE-7M4) with a macro lens (SEL50M28) to record experimental phenomena in real time and realize the synchronous acquisition of mechanical and optical signals.

[0028] The material of the mechanoluminescent particles is [(3ZnS / 2CaZnOS)]. 0.98 SrZnOS 0.02 2%Mn 2+ [[3ZnS / 2CaZnOS]] / Al2O3 composite. The particulate material is a modified mechanoluminescent composite material. 0.98 SrZnOS 0.02 2%Mn 2+ The luminescence intensity of the α / Al2O3 composite can respond promptly to local stress and exhibits a certain linear relationship.

[0029] This utility model also provides a method for visualizing force chains based on a mechanoluminescent particle system 8, implemented according to a force chain visualization model device based on the mechanoluminescent particle system 8, which includes the following steps:

[0030] S1. Set up a darkroom and place the LCD micro-controlled ring shearing device 2 inside the darkroom;

[0031] S2. Mount the fully transparent shearing box 1 on the lower pressure plate 4 of the LCD micro-controlled ring shear 2 and tighten the six bolts 12 to fix it;

[0032] S3. Evenly pack 0.5mm diameter mechanoluminescent particles into the fully transparent shear box 1 to a height slightly below the upper edge of the fully transparent shear box 1 to form a particle system 8, and make the upper surface of the particle system 8 flush.

[0033] S4. Place the upper pressure plate 3 on the upper surface of the particle system 8, and support the side of the upper pressure plate 3 on the telescopic rod 9 of the liquid crystal micro-controlled ring shear 2. Install the support rod 10 on the liquid crystal micro-controlled ring shear 2, and tighten the two bolts 12 on the left and right to fix the support plate 11 on the support rod 10 of the liquid crystal micro-controlled ring shear 2, so that the support plate 11 is located above the upper pressure plate 3.

[0034] S5. Place the measuring end of the displacement gauge 5 on the top center of the upper pressure plate 3 and the support plate 11 respectively, and zero the displacement gauge 5;

[0035] S6. A weight pan 16 is suspended at the bottom of the LCD micro-controlled ring shear apparatus 2 by a single lever-type normal loading component, and weights are placed on the weight pan 16 according to the vertical load required for the test.

[0036] S7. Set up and fix the camera at a horizontal distance of about 15cm from the particle system 8, with the camera lens facing the particle system 8.

[0037] S8. Turn on the LCD micro-control ring shear apparatus 2, open the ring shear apparatus control software through computer 14, set the sample parameters and test program. The sample parameters include height (mm), outer diameter (mm), inner diameter (mm), etc.; the test program includes three modules: data acquisition, standard consolidation, and single-stage shear. In the data acquisition module: set the maximum test time to 1 min, the sampling interval to 3 s, and keep the pressure constant at the end of the test. In the standard consolidation module: set the current value of normal stress to 0, the target value to be the weight of the weight on the weight plate 16, the maximum test time to 1 min, and keep the pressure constant at the end of the test. In the single-stage shear module: set the current value and target value of normal stress to be the weight of the weight on the weight plate 16, the shear rate (° / min), the maximum test time, the cyclic shear mode, and keep the pressure constant at the end of the test.

[0038] S9. Turn on the camera's video recording mode, start the LCD micro-controlled ring shear 2, and begin shearing; the camera captures a video of the changes in the particle system 8, the LCD micro-controlled ring shear 2 collects the vertical displacement data of the displacement gauge 5 and the shearing force data through the built-in LCD micro-controlled ring shear 2, and transmits the data to the computer 14;

[0039] S10. After the shearing is complete, turn off the camera. The computer 14 will generate and export in real-time the vertical displacement-time and shearing force-time curves and specific values ​​of the LCD micro-controlled ring shearer 2. The captured video will be exported via the camera. The vertical displacement-time and shearing force-time are automatically generated by the computer's built-in program, and the specific values ​​can be exported from the computer via a txt text file.

[0040] This utility model can achieve the following technical effects:

[0041] Visualization of interparticle contact forces and force chains: Using a fully transparent shear box 1 and mechanoluminescent particles, and a camera equipped with a macro lens to capture experimental phenomena in real time, it can be observed that when shearing occurs, the contact between particles emits yellow light, and the greater the shearing force, the stronger the light emission. This achieves synchronous visualization of the interparticle contact forces and the force chain transmission of the particle system.

[0042] A low-cost and easy-to-operate experimental platform was developed: using a transparent liquid crystal micro-controlled ring shearing instrument 2 and a camera, the simultaneous acquisition of mechanical (shear force and vertical displacement) and optical signals can be realized, and the stress situation of the complex particle system 8 can be further investigated.

[0043] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the protection scope of the present invention.

Claims

1. A force chain visualization model device based on a force luminescent particle system, characterized in that, The device includes a fully transparent shearing box, a liquid crystal micro-controlled circumferential shearing device, an upper pressure plate, a lower pressure plate, a displacement meter, and a camera module. The lower pressure plate is connected to the liquid crystal micro-controlled circumferential shearing device. The bottom of the fully transparent shearing box is fixed to the lower pressure plate. The fully transparent shearing box is filled with mechanoluminescent particles to form a particle system. The upper surface of the particle system is flattened. The upper pressure plate is placed on the upper surface of the particle system. The displacement meter is installed on top of the upper pressure plate. The camera module is mounted horizontally on the fully transparent shearing box and aligned with the particle system. The liquid crystal micro-controlled circumferential shearing device is equipped with a control display.

2. The device for visualizing force chains based on a force-induced luminescent particle system according to claim 1, characterized in that It also includes a telescopic rod, the bottom of which is connected to the LCD micro-controlled ring shear, and the top of which is connected to a pressure plate.

3. The device for visualizing force chains based on a force-induced luminescent particle system according to claim 1, characterized in that It also includes a support rod and a support plate. The support rod is mounted on the LCD micro-controlled ring shearing instrument, and the support plate is fixed on the support rod. The support plate is located above the upper pressure plate, and the measuring end of the displacement gauge is connected to the support plate and the upper pressure plate respectively.

4. The device for visualizing force chains based on a force-induced luminescent particle system according to claim 1, characterized in that The fully transparent shear box has a particle slot inside, and the bottom of the upper pressure plate has a pressure block. The pressure block matches the slot of the particle slot. After the particle slot is filled with force luminescent particles and leveled, the pressure block is placed on the upper surface of the particle system.

5. The force chain visualization model apparatus based on the force-induced light particle system according to claim 1, wherein, It also includes a computer connected to a liquid crystal micro-controlled ring shearing device.

6. The force chain visualization model apparatus based on the force-induced luminescent particle system according to claim 1, wherein, It also includes a weight pan for placing weights, which is connected to the bottom of the LCD micro-controlled ring shearing device.

7. The device for visualizing force chains based on a force-induced luminescent particle system according to claim 1, characterized in that The camera module is a camera or a video camera.

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