A device and method for monitoring the creep properties of large-size coarse-grained soils

Abstract

The application provides a large-size coarse-grained soil creep characteristic monitoring device and method, and relates to the technical field of rock mechanics, and comprises a hollow rectangular section of a support structure, a creep measurement device arranged on the bottom surface of the support structure; the loading system comprises a first loading device and a second loading device, the first loading device is arranged on the top surface of the support structure, the second loading device is arranged on the other wall surface of the support structure, and the detection ends of the first loading device and the second loading device are in contact with the other wall surface of the creep measurement device away from the ground; the scanning device is arranged on the first loading device, and the scanning end of the scanning device extends away from the top surface of the support structure. The application solves the problem of insufficient stress control precision.

Description

Technical Field

[0001] This invention relates to the field of rock mechanics, and more specifically, to a device and method for monitoring the creep characteristics of large-sized coarse-grained soil. Background Technology

[0002] In rock mechanics, current experimental methods for creep measurement mainly include uniaxial and triaxial tests, primarily used to investigate the creep characteristics of different types of coarse-grained soils. While uniaxial tests offer the advantage of ease of operation, they can only apply uniaxial stress, making it difficult to simulate the complex multiaxial stress states faced by soil in actual engineering projects. Triaxial tests can simulate triaxial stress states, but their loading method is relatively fixed, typically controlling stress conditions by adjusting confining pressure and axial pressure. For some large-sized coarse-grained soils, this fixed loading method has limitations; it cannot fully simulate the complex stress changes experienced by soil in actual engineering projects, nor can it accommodate the true gradation of coarse-grained soils, leading to insufficient stress control accuracy.

[0003] Therefore, there is an urgent need for a monitoring device and method for the creep characteristics of large-sized coarse-grained soil, which solves the problem of insufficient stress control accuracy. Summary of the Invention

[0004] The purpose of this invention is to provide a device and method for monitoring the creep characteristics of large-sized coarse-grained soil, so as to improve the above-mentioned problems. To achieve the above objective, the technical solution adopted by this invention is as follows:

[0005] In a first aspect, this application provides a creep characteristic monitoring device for large-size coarse-grained soil, comprising: a support structure with a hollow rectangular cross-section, and a creep measuring device disposed on the bottom surface of the support structure; a multi-directional loading system, the loading system comprising a first loading device and a second loading device, the first loading device being disposed on the top surface of the support structure, the second loading device being disposed on other walls of the support structure, the detection ends of the first loading device and the second loading device contacting other walls of the creep measuring device away from the ground; and a scanning device disposed on the first loading device, the scanning end of the scanning device extending along the top surface away from the support structure.

[0006] Secondly, this application also provides a method for monitoring the creep characteristics of large-sized coarse-grained soil, including:

[0007] During the creep monitoring phase, a creep measuring device is installed, and large-sized coarse-grained soil is buried in the pressure structure of the creep measuring device to perform multi-dimensional creep detection and obtain multi-dimensional monitoring parameters.

[0008] The large-sized coarse-grained soil was subjected to cross-sectional scanning and radio frequency identification. The particle motion trajectory was obtained by spatiotemporal registration of the cross-sectional scanning data and radio frequency identification data.

[0009] By coupling the multi-dimensional monitoring parameters and the particle motion trajectory, a physical model of soil creep is obtained;

[0010] After the creep monitoring phase, the large-sized coarse-grained soil was subjected to destructive treatment and surface cracks were detected. The failure mode analysis results were obtained by comparing and analyzing the surface cracks with the preset tomographic scan data.

[0011] Based on the physical model of soil creep and the analysis results of the failure mode, the characteristic prediction results are constructed.

[0012] The beneficial effects of this invention are as follows:

[0013] This invention utilizes multi-dimensional creep detection to comprehensively acquire creep parameters of large-sized coarse-grained soils, overcoming the limitations of traditional single-dimensional monitoring and resulting in more accurate and comprehensive data. By combining cross-sectional scanning and radio frequency identification (RFID) technologies, it accurately tracks particle movement trajectories, revealing in-depth changes in the soil's internal structure. A soil creep physical model, constructed based on the coupling of multi-dimensional monitoring parameters and particle movement trajectories, accurately reflects the actual physical process of soil creep. The failure mode analysis results, combined with the creep physical model, are used to understand soil failure behavior, improving the accuracy of soil failure mode prediction. In summary, this invention solves the problem of insufficient stress control precision.

[0014] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing embodiments of the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is an overall schematic diagram of a creep characteristic monitoring device for large-size coarse-grained soil as described in an embodiment of the present invention.

[0017] Figure 2 This is a perspective view of the pressure structure described in an embodiment of the present invention;

[0018] Figure 3 This is a schematic diagram of the loading plate structure described in an embodiment of the present invention;

[0019] Figure 4 This is a schematic diagram of a method for monitoring the creep characteristics of large-sized coarse-grained soil according to an embodiment of the present invention.

[0020] Figure 5 This is a schematic diagram of a creep characteristic monitoring device for large-sized coarse-grained soil as described in an embodiment of the present invention.

[0021] The diagram shows: 1. Support structure; 2. Creep measuring device; 3. First loading device; 4. Second loading device; 5. Scanning device; 6. Force sensor; 21. Pressure structure; 41. Hydraulic cylinder; 42. Loading plate; 211. Baffle; 212. Support plate; 800. A creep characteristic monitoring device for large-size coarse-grained soil; 801. Processor; 802. Memory; 803. Multimedia component; 804. I / O interface; 805. Communication component. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0023] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this invention, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0024] Example 1:

[0025] like Figure 1As shown, a creep characteristic monitoring device for large-sized coarse-grained soil includes: a support structure 1 with a hollow rectangular cross-section, and a creep measuring device 2 disposed on the bottom surface of the support structure 1; a multi-directional loading system, including a first loading device 3 and a second loading device 4, the first loading device 3 being disposed on the top surface of the support structure 1, and the second loading device 4 being disposed on other wall surfaces of the support structure 1, the detection ends of the first loading device 3 and the second loading device 4 contacting other wall surfaces of the creep measuring device 2 away from the ground; and a scanning device 5 disposed on the first loading device 3, the scanning end of the scanning device 5 extending along the top surface away from the support structure 1. The specific implementation process of this invention is as follows: the prepared large-sized coarse-grained soil is buried in the creep measuring device 2; the first loading device 3 and the second loading device 4 are activated to move in a preset direction; during the loading process, the detection ends of the first loading device 3 and the creep measuring device 2 contact the creep measuring device 2 and apply pressure; the scanning device 5 is used to perform real-time full-section scanning of the creep measuring device 2 to obtain deformation information of the sample in different directions.

[0026] Preferably, the scanning device 5 includes a flat-panel cesium iodide scintillator detector and a rotating anode high-frequency X-ray generator.

[0027] To clarify the specific results of the creep measurement device 2, the creep measurement device 2 includes a pressure structure 21 and a temperature control structure. The temperature control structure is disposed on the inner wall surface of the pressure structure 21 and is electrically connected to the pressure structure 21.

[0028] like Figure 2 As shown, the pressure structure 21 includes two baffles 211 and two support plates 212. The two baffles 211 are arranged opposite to each other, and the two support plates 212 are arranged opposite to each other. The baffles 211 and the support plates 212 are arranged adjacent to each other. The two side walls of the two baffles 211 are fixedly connected to the side walls of the two support plates 212 to form a rectangle. In this structure, the baffles 211 are hollow structures, and the outer wall of the support plates 212 is provided with a support structure. The support structure is used to enhance the overall strength and stability of the pressure chamber. The tops of the baffles 211 and the support plates 212 are hollow structures. The first loading device 3 passes through the hollow structure to contact and apply pressure to the large-sized coarse-grained soil, and the second loading device 4 passes through the hollow structure to contact and apply pressure to the large-sized coarse-grained soil.

[0029] Preferably, the baffle 211, the support plate 212 and the support structure are all detachable, which can be used to adjust and optimize the specimen size to meet different test requirements.

[0030] In this structure, the second loading device 4 is equipped with a hydraulic cylinder 41, which is laterally arranged along the side wall of the support structure 1. One end of the hydraulic cylinder 41 is connected to the side wall of the support structure 1, and the other end of the hydraulic cylinder 41 is equipped with a loading plate 42. The hydraulic cylinder 41 moves along the side wall away from the support structure 1, and the hydraulic cylinder 41 drives the detection end of the loading plate 42 to contact the creep measuring device 2. A flexible graphite sealing strip is provided on the edge of the loading plate 42, which is used to adjust the position offset at the contact point between the loading plate 42 and the creep measuring device 2. The second loading device 4 is used to apply axial principal compressive stress and lateral compressive stress to the large-sized coarse-grained soil to simulate the stress state of the soil in actual engineering.

[0031] Preferably, the hydraulic cylinder 41 is a double-acting piston cylinder (cylinder diameter 150mm, rod diameter 70mm, stroke ±200mm) with a pressure resistance of 35Mpa.

[0032] like Figure 3 As shown, the loading plate 42 has a honeycomb cross-section. Preferably, the loading plate 42 is made of honeycomb titanium alloy material, and its overall cross-section has a honeycomb structure. Particles are placed in the honeycomb holes of the honeycomb structure. Through the filling of particles, stress can be further dispersed and stress concentration can be avoided. The surface of the loading plate 42 is also provided with a silicon carbide coating to improve its wear resistance and corrosion resistance.

[0033] Furthermore, each end of the hydraulic cylinder 41 is provided with a force sensor 6, and the detection end of the force sensor 6 extends along the side wall away from the support structure 1. Preferably, the force sensor 6 is a piezoelectric quartz force sensor.

[0034] In this invention, the temperature control structure includes a thermally conductive layer, a semiconductor layer, and a thermal insulation layer. The semiconductor layer is electrically connected to both the thermally conductive layer and the thermal insulation layer. The thermally conductive layer is located in the inner layer and is constructed as a copper tube spirally coiled around the outer surface of the large-sized coarse-grained soil. Silicone oil circulates inside the tube, and heat is transferred through a liquid cooling / heating medium to achieve a rapid temperature response. The semiconductor layer is located in the middle layer and is arranged in a Peltier module array, achieving localized rapid heating or cooling by switching the current direction. The thermal insulation layer is located in the outer layer and is made of nano-aerogel felt with a stainless steel shell on its outer wall to isolate external thermal interference and maintain the stability of the internal temperature field of the sample. This temperature control structure is used to simulate complex temperature environments in actual engineering, including the low-temperature environment of frozen soil regions and the high-temperature environment of tropical regions, and to study the influence of temperature gradient changes on soil creep rate and particle contact force.

[0035] Example 2: This example provides a method for monitoring the creep characteristics of large-sized coarse-grained soil.

[0036] See Figure 4 The figure shows that the method includes steps S1 to S5, including:

[0037] S1: Creep monitoring stage, install creep measuring device 2, bury large-sized coarse soil in the pressure structure 21 of the creep measuring device to perform multi-dimensional creep detection, and obtain multi-dimensional monitoring parameters;

[0038] In this step, the large-sized coarse-grained soil is filled in layers: the soil is filled in 12 layers, each 50mm thick. Each layer is compacted three times after filling to ensure uniform density; density testing: a nuclear density meter is used to test three points (center and two symmetrical points) for each layer, requiring a dry density ρ d =2.1±0.02g / cm 3 If the density is insufficient in some areas, fill with soil particles and then recompact.

[0039] To clarify the specific methods for obtaining multi-dimensional monitoring parameters, step S1 includes S11 to S15, specifically:

[0040] S11: Install creep measuring device 2, bury large-sized coarse soil in the pressure structure 21 of creep measuring device for pressure detection, and obtain the initial pressure value;

[0041] S12: In the initial creep stage, pressure is applied to the large-sized coarse-grained soil according to the dynamic friction compensation model and the initial pressure value to obtain the stress field setting value;

[0042] In this step, the initial pressure value is input into the dynamic friction compensation model to calculate the applied pressure value. The calculated pressure value is applied to the large-sized coarse-grained soil through the first loading device 3 and the second loading device 4. During this process, the closed-loop feedback control principle is adopted to ensure that the stress field inside the sample can be accurately tracked and reach the preset value, thereby effectively solving the stress drift problem caused by boundary friction and hydraulic hysteresis in traditional equipment.

[0043] The application mechanism of the dynamic friction compensation model in friction compensation is as follows: A hyperbolic tangent function is introduced to dynamically correct the boundary friction force, thus solving the error of the traditional Coulomb friction model under high loading rates. The traditional Coulomb friction model assumes constant friction force, but in coarse-grained soil experiments, particle embedding in the pores of the loading plate causes the friction coefficient to change with the loading rate. The hyperbolic tangent function describes the friction state from static friction (μ→μ0 when v→0) to kinetic friction (v>v). c A smooth transition from μ to 0.8μ0;

[0044] The application mechanism of the dynamic friction compensation model in boundary stress correction is as follows: dynamic compensation of rate-dependent frictional force is achieved through the hyperbolic tangent function, eliminating boundary effects. When calculating the effective loading force by integration, the additional stress caused by lateral friction is automatically deducted to ensure uniform stress field inside the sample.

[0045] The expression for the dynamic friction compensation model is:

[0046]

[0047] In equation (1) above, F i Indicates the effective applied stress, A i σ represents the effective area of ​​the loading plate in direction i. i σ represents the applied pressure with principal stress direction i, μ(v, h) represents the rate-dependent friction coefficient, v represents the instantaneous loading rate of the loading plate, h represents the depth of particle embedding in the loading plate pores, and σ j dA represents the applied pressure in the direction of principal stress j, and dA represents the pressure applied to area A during the integration process. i The tiny division, d represents the tiny change.

[0048] S13: Main creep stage, based on constant triaxial stress, the pressure structure 21 is subjected to temperature adjustment simulation daily cycle to obtain the main creep termination value;

[0049] In this step, the triaxial stress is kept constant, and the temperature control system is coupled with the daily cycle temperature.

[0050] The temperature control equation is as follows:

[0051]

[0052] In equation (2) above, T(t) represents the temperature control value, t represents the time variable, and T base The reference temperature is represented by ΔT, the temperature amplitude by ΔT, sin represents the sine function, π represents pi, t0 represents the initial time offset, and T represents the reference temperature. cycle Indicates the cycle period.

[0053] S14: Accelerated creep stage, based on the main creep termination value, an increasing axial stress is applied to the large-sized coarse-grained soil to obtain the creep failure early warning threshold;

[0054] In this step, an increasing axial stress is applied to the large-sized coarse-grained soil to induce progressive failure of the sample, capture early signs of failure, and thus establish a creep failure warning threshold.

[0055] Failure criteria include axial strain criterion, volumetric strain rate criterion, and shear band criterion; the experiment is stopped if any one of them is met.

[0056] Among them, the axial strain criterion is ε1>15%, and the volumetric strain rate criterion is... The duration is 24 hours; the shear band criterion is that the volume percentage of the shear band is >10%;

[0057] The formula for increasing axial stress is:

[0058]

[0059] In equation (3) above, σ1(t) represents the axial stress at time t, σ 1,0 Indicates the initial axial stress during the acceleration phase. t represents the rate of increase of axial stress. ＇ t represents the cumulative time of the experiment. acc_start This indicates the start time of the acceleration phase.

[0060] S15: Based on the stress field setpoint, the main creep termination value, and the creep failure early warning threshold, multi-dimensional monitoring parameters are constructed to obtain them.

[0061] In this step, the multi-dimensional monitoring parameters include stress, deformation, and temperature parameters.

[0062] S2: Perform cross-sectional scanning and radio frequency identification on the large-sized coarse-grained soil, and obtain the particle motion trajectory by performing spatiotemporal registration processing on the cross-sectional scanning data and radio frequency identification data;

[0063] To clarify the specific method for obtaining the particle motion trajectory, step S2 includes S21 to S25, specifically:

[0064] S21: Perform high-frequency cross-sectional scanning on the large-sized coarse grains to obtain three-dimensional voxel data;

[0065] S22: Based on the preset dense packing pattern, passive radio frequency identification tags are placed on the large-sized coarse-grained soil and signals are collected to obtain radio frequency identification signals;

[0066] In this step, the dense packing pattern refers to the reasonable arrangement of radio frequency identification tags based on the natural packing state of soil particles to ensure that the tags can cover the key areas of the soil. This solves the problem that traditional methods are difficult to track the movement of particles inside the soil in real time, and improves the real-time and dynamic nature of monitoring.

[0067] S23: Based on the three-dimensional voxel data and the radio frequency identification signal, perform spatiotemporal registration processing to obtain the precise coordinates of the particles;

[0068] To clarify the specific method for obtaining the precise coordinates of the particles, step S23 includes S231 to S234, specifically:

[0069] S231: Based on the three-dimensional voxel data and the radio frequency identification signal, the matching error is minimized to obtain the grayscale difference;

[0070] In this step, the grayscale difference is used to reflect the degree of matching between the three-dimensional voxel data and the radio frequency identification signal in spatial location. The smaller the grayscale difference, the more accurate the matching.

[0071] S232: Calculate the regularization term on the three-dimensional voxel data according to the three-dimensional Laplacian operator to obtain the image smoothness;

[0072] In this step, the three-dimensional Laplacian operator is used to detect edges and discontinuities in the image to avoid abrupt changes caused by noise. The image smoothness is used to reflect the smoothness of the three-dimensional voxel data. The higher the smoothness, the less noise and discontinuities are in the image.

[0073] S233: Determine the particle region range based on the intensity of the radio frequency identification signal to obtain the particle region result;

[0074] S234: Optimize and adjust the coordinates in the particle region result based on the grayscale difference and the image smoothness to obtain the precise coordinates of the particles.

[0075] S24: Calculate the migration rate of the precise coordinates of the particle to obtain the migration rate result;

[0076] In this step, the migration rate expression is:

[0077]

[0078] In equation (4) above, v p This represents the migration rate of each labeled particle, where t1 represents the start time and t2 represents the end time. Represents the velocity vector Size, Let dt represent the rate at which position P changes with time t, and dt represent a small time increment.

[0079] S25: Perform Kalman filtering on the precise coordinates of the particle based on the migration rate result to obtain the particle's motion trajectory.

[0080] In this step, the Kalman filter is used to effectively remove noise, improve the smoothness and accuracy of particle motion trajectory, solve the problem of noise interference in particle motion trajectory in traditional methods, and improve the reliability of trajectory.

[0081] S3: Based on the coupling of the multi-dimensional monitoring parameters and the particle motion trajectory, a physical model of soil creep is obtained;

[0082] To clarify the specific method for obtaining the physical model of soil creep, step S3 includes S31 to S34, specifically:

[0083] S31: Based on the distribution of the multi-dimensional monitoring parameters and the particle motion trajectory, a physical model is obtained;

[0084] S32: The physical model is calculated based on the modified fractional creep model to obtain the creep response of the soil;

[0085] In this step, the expression for the modified fractional-order creep model is:

[0086]

[0087] In equation (5) above, ε(t) represents the creep strain at time t, σ0 represents the initial stress, E represents the elastic modulus of the material, and σ ref denoted as reference stress, m as stress sensitivity index, t as time variable, t3 and t4 as characteristic times, α and β as model parameters, and ln as the natural logarithm function.

[0088] S33: Based on the creep response of the soil, the parameters in the physical model are optimized using the nonlinear least squares method to obtain the optimized model parameters;

[0089] In this step, the model parameters are optimized using the nonlinear least squares method, which solves the problem of large prediction errors caused by unreasonable initial settings of model parameters, and improves the accuracy of model parameters and the predictive ability of the model.

[0090] S34: Based on the characteristic length scale, the optimized model parameters are size-corrected to construct a physical model of soil creep.

[0091] In this step, the optimized model parameters are corrected based on the characteristic length scale, which solves the problem that the traditional model does not consider the actual size of the soil, resulting in the model not matching reality.

[0092] The size correction expression is:

[0093]

[0094] In equation (6) above, ε corr This represents the corrected strain value, ε. meas L represents the measured strain value. c D represents the feature length scale. 50 Indicates the characteristic particle size.

[0095] S4: After the creep monitoring stage is completed, the large-sized coarse-grained soil is subjected to destructive treatment and surface cracks are detected. The failure mode analysis results are obtained by comparing and analyzing the surface cracks and the preset tomographic scan data.

[0096] To clarify the specific method for obtaining the damage mode analysis results, step S4 includes S41 to S44, specifically:

[0097] S41: After the creep monitoring stage is completed, the large-sized coarse-grained soil is subjected to axial load and destructive treatment to obtain a destructive coarse-grained soil sample.

[0098] In this step, the axial load is retained to simulate the failure of soil under stress in actual engineering, and to ensure that the specimen after failure treatment can truly reflect the mechanical behavior of soil during creep.

[0099] S42: Surface crack detection is performed on the damaged coarse-grained soil sample to obtain crack detection results;

[0100] S43: Based on the comparison between the crack detection results and the tomographic scan data, a comparison result is obtained;

[0101] S44: Conduct an in-depth analysis of the comparison results, and combine the deformation characteristics and stress state of the large-sized coarse-grained soil during the creep process to obtain the failure mode analysis results.

[0102] In this step, the failure mode analysis results are used to determine the failure mode of the soil, such as shear failure, tensile failure, or combined failure.

[0103] S5: Based on the physical model of soil creep and the analysis results of the failure mode, the characteristic prediction results are constructed.

[0104] Example 3:

[0105] Corresponding to the above method embodiments, this embodiment also provides a creep characteristic monitoring device for large-sized coarse-grained soil. The creep characteristic monitoring device for large-sized coarse-grained soil described below and the creep characteristic monitoring method for large-sized coarse-grained soil described above can be referred to in correspondence with each other.

[0106] Figure 5 This is a block diagram illustrating a creep characteristic monitoring device 800 for large-sized coarse-grained soil according to an exemplary embodiment. Figure 5 As shown, the creep characteristic monitoring device 800 for large-sized coarse-grained soil may include: a processor 801 and a memory 802. The device 800 may also include one or more of the following: a multimedia component 803, an I / O interface 804, and a communication component 805.

[0107] The processor 801 controls the overall operation of the creep characteristic monitoring device 800 for large-size coarse-grained soil to complete all or part of the steps in the aforementioned creep characteristic monitoring method for large-size coarse-grained soil. The memory 802 stores various types of data to support the operation of the creep characteristic monitoring device 800 for large-size coarse-grained soil. This data may include, for example, instructions for any application or method operating on the creep characteristic monitoring device 800 for large-size coarse-grained soil, as well as application-related data, such as contact data, sent and received messages, images, audio, video, etc. The memory 802 can be implemented using any type of volatile or non-volatile storage device or a combination thereof, such as Static Random Access Memory (SRAM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Erasable Programmable Read-Only Memory (EPROM), Programmable Read-Only Memory (PROM), Read-Only Memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The multimedia component 803 may include a screen and an audio component. The screen may be, for example, a touchscreen, and the audio component is used to output and / or input audio signals. For example, the audio component may include a microphone for receiving external audio signals. The received audio signals may be further stored in the memory 802 or transmitted via the communication component 805. The audio component also includes at least one speaker for outputting audio signals. I / O interface 804 provides an interface between processor 801 and other interface modules, such as keyboards, mice, and buttons. These buttons can be virtual or physical. Communication component 805 is used for wired or wireless communication between the large-size coarse-grained soil creep characteristic monitoring device 800 and other devices. Wireless communication includes Wi-Fi, Bluetooth, Near Field Communication (NFC), 2G, 3G, or 4G, or a combination thereof. Therefore, the corresponding communication component 805 may include a Wi-Fi module, a Bluetooth module, or an NFC module.

[0108] In an exemplary embodiment, a creep characteristic monitoring device 800 for large-size coarse-grained soil can be implemented by one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), controllers, microcontrollers, microprocessors, or other electronic components to perform the aforementioned creep characteristic monitoring method for large-size coarse-grained soil.

[0109] Example 4:

[0110] Corresponding to the above method embodiments, this embodiment also provides a medium. The medium described below can be referred to in conjunction with the creep characteristic monitoring method for large-size coarse-grained soil described above.

[0111] A medium storing a computer program, which, when executed by a processor, implements the steps of a method for monitoring the creep characteristics of large-sized coarse-grained soil according to the above-described method embodiments.

[0112] The medium can specifically be any medium capable of storing program code, such as a USB flash drive, external hard drive, read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk.

[0113] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0114] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for monitoring the creep characteristics of large-sized coarse-grained soil, wherein the method uses a creep characteristic monitoring device for large-sized coarse-grained soil, as detailed below: The support structure (1) has a hollow rectangular cross section and a creep measuring device (2) is provided on the bottom surface of the support structure (1). A multi-directional loading system, comprising a first loading device (3) and a second loading device (4), wherein the first loading device (3) is disposed on the top surface of the support structure (1), and the second loading device (4) is disposed on other wall surfaces of the support structure (1), wherein the detection ends of the first loading device (3) and the second loading device (4) are in contact with other wall surfaces away from the ground of the creep measuring device (2); A scanning device (5) is disposed on the first loading device (3), and the scanning end of the scanning device (5) extends along the top surface away from the support structure (1); The creep measuring device (2) includes a pressure structure (21) and a temperature control structure. The temperature control structure is disposed on the inner wall surface of the pressure structure (21) and is electrically connected to the pressure structure (21). The pressure structure (21) includes two baffles (211) and two support plates (212). The two baffles (211) are arranged opposite to each other, and the two support plates (212) are arranged opposite to each other. The baffles (211) and the support plates (212) are arranged adjacent to each other. The two side walls of the two baffles (211) are fixedly connected to the side walls of the two support plates (212) to form a rectangle. The second loading device (4) is equipped with a hydraulic cylinder (41). The hydraulic cylinder (41) is arranged laterally along the side wall of the support structure (1). One end of the hydraulic cylinder (41) is connected to the side wall of the support structure (1). The other end of the hydraulic cylinder (41) is equipped with a loading plate (42). The hydraulic cylinder (41) moves along the side wall away from the support structure (1). The hydraulic cylinder (41) drives the detection end of the loading plate (42) to contact the creep measuring device (2). The cross-section of the loading plate (42) is honeycomb-shaped; characterized in that, include: During the creep monitoring stage, a creep measuring device (2) is installed, and large-sized coarse-grained soil is buried in the pressure structure (21) of the creep measuring device (2) to perform multi-dimensional creep detection and obtain multi-dimensional monitoring parameters. The large-sized coarse-grained soil was subjected to cross-sectional scanning and radio frequency identification. The particle motion trajectory was obtained by spatiotemporal registration of the cross-sectional scanning data and radio frequency identification data. By coupling the multi-dimensional monitoring parameters and the particle motion trajectory, a physical model of soil creep is obtained; The specific methods for obtaining the physical model of soil creep include: By combining the distribution of the multi-dimensional monitoring parameters with the particle motion trajectory, a physical model is obtained; The physical model was calculated based on the modified fractional creep model to obtain the creep response of the soil. The expression for the modified fractional-order creep model is: ； In the above formula, express creep strain at time, Indicates the initial stress. Indicates the elastic modulus of a material. Indicates the reference stress. Indicates the stress sensitivity index. Represents a time variable. , Both represent characteristic times. , All represent model parameters. Represents the natural logarithm function; Based on the creep response of the soil, the parameters in the physical model are optimized using the nonlinear least squares method to obtain the optimized model parameters; Based on the characteristic length scale, the optimized model parameters are size-corrected to construct a physical model of soil creep. After the creep monitoring phase, the large-sized coarse-grained soil was subjected to destructive treatment and surface crack detection. The failure mode analysis results were obtained by comparing and analyzing the surface crack data with the preset tomographic scan data. Based on the physical model of soil creep and the analysis results of the failure mode, the characteristic prediction results are constructed.

2. The method for monitoring the creep characteristics of large-sized coarse-grained soil according to claim 1, characterized in that, During the creep monitoring phase, a creep measuring device (2) is installed, and large-sized coarse-grained soil is buried in the pressure structure (21) of the creep measuring device (2) for multi-dimensional creep detection to obtain multi-dimensional monitoring parameters, including: Install the creep measuring device (2), bury the large-sized coarse-grained soil in the pressure structure (21) of the creep measuring device for pressure detection, and obtain the initial pressure value; In the initial creep stage, pressure is applied to the large-sized coarse-grained soil according to the dynamic friction compensation model and the initial pressure value to obtain the stress field setting value; During the main creep stage, the pressure structure (21) is subjected to temperature adjustment simulation daily cycle based on constant triaxial stress to obtain the main creep termination value; During the accelerated creep stage, an increasing axial stress is applied to the large-sized coarse-grained soil based on the main creep termination value to obtain the creep failure early warning threshold. Multi-dimensional monitoring parameters are constructed based on the stress field setpoint, the main creep termination value, and the creep failure early warning threshold.

3. The method for monitoring the creep characteristics of large-sized coarse-grained soil according to claim 1, characterized in that, The large-sized coarse-grained soil was subjected to cross-sectional scanning and radio frequency identification (RFID). Spatiotemporal registration processing was performed on the cross-sectional scanning data and RFID data to obtain the particle motion trajectory, including: High-frequency cross-sectional scanning was performed on the large-sized coarse-grained soil to obtain three-dimensional voxel data; Based on a preset dense packing pattern, passive radio frequency identification (RFID) tags are placed on the large-sized coarse-grained soil and signals are collected to obtain RFID signals; Spatiotemporal registration processing is performed based on the three-dimensional voxel data and the radio frequency identification signal to obtain the precise coordinates of the particles; The migration rate of the particle's precise coordinates is calculated to obtain the migration rate result; Based on the migration rate results, Kalman filtering is performed on the precise coordinates of the particle to obtain the particle's trajectory.

4. The method for monitoring the creep characteristics of large-sized coarse-grained soil according to claim 3, characterized in that, Based on the three-dimensional voxel data and the radio frequency identification signal, spatiotemporal registration processing is performed to obtain the precise coordinates of the particles, including: Based on the three-dimensional voxel data and the radio frequency identification signal, the minimum matching error is calculated to obtain the grayscale difference; The image smoothness is obtained by calculating the regularization term on the three-dimensional voxel data using the three-dimensional Laplacian operator. The particle region range is determined based on the intensity of the radio frequency identification signal, and the particle region result is obtained; The coordinates in the particle region result are optimized and adjusted based on the grayscale difference and the image smoothness to obtain the precise coordinates of the particles.

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