A soil body deformation analysis method and system based on energy change rate

Abstract

The application discloses a kind of soil deformation analysis method and system based on energy change rate, comprising: obtaining the stress-strain data of soil by triaxial shear test;Based on the principle of energy conservation, the energy change rate under unit shear strain is calculated;Draw and identify the morphological characteristics of energy change rate-shear strain relationship curve, especially the platform-slow descent characteristics presented in shear failure stage;Based on the state-dependent dilatancy theory, an analytical relationship between energy change rate and soil dilatancy parameters is established;Combined with the curve characteristics and analytical relationship, an explicit constitutive relationship model between stress ratio and dilatancy parameters is constructed.The model can be used to directly judge the stability of soil deformation or calibrate the constitutive model parameters.The application reveals the coupling mechanism of soil strain softening and dilatancy behavior from a new perspective of energy compensation, dynamically correlates macroscopic mechanical response with microscopic parameters, and provides a theoretical basis and practical tool for soil constitutive model development and engineering stability analysis.

Description

Technical Field

[0001] This invention relates to the field of geotechnical engineering technology, and more specifically to a method and system for analyzing soil stress-strain relationship based on energy change rate, which is particularly suitable for analyzing the strain softening and shear dilatation coupling behavior of granular soils such as saturated sand during shearing. Background Technology

[0002] The stress-strain relationship in soil exhibits significant nonlinear characteristics and is traditionally described using deviatoric stress-strain curves, which are categorized into strain hardening and strain softening. For strain hardening behavior, relatively mature mathematical models exist (such as the Duncan-Chang model and the Lade-Duncan model). However, describing and modeling strain softening and dilatation behaviors remains challenging, primarily due to the complex curve shapes and the unclear coupling mechanism between volume change and strength attenuation.

[0003] Classical dilatation theory, such as the Rowe equation, considers the dilatation parameter... While treating stress-strain as a constant or a simple function, or expressing it as a function of state parameters, it still fails to reveal the intrinsic compensation mechanism between strain softening and shear dilatation from an energy perspective. Traditional stress-strain analysis often focuses on the response in one direction, failing to fully couple the energy conversion processes of stress and strain in all directions during shearing.

[0004] In recent years, constitutive modeling research based on thermodynamics and energy principles has made some progress, but a complete analytical method has not yet been formed to directly extract energy evolution characteristics from experimental data and use them to reveal the soil softening-dilatation coupling mechanism.

[0005] Therefore, how to design a soil deformation analysis method and system that can reveal the energy absorption, transformation and dissipation mechanism in the soil deformation process from the perspective of energy conservation is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0006] In view of the above problems, the present invention is proposed to provide a soil deformation analysis method and system based on energy change rate to overcome or at least partially solve the above problems, providing a new approach to understanding soil strain softening behavior and developing corresponding constitutive models.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] In a first aspect, embodiments of the present invention provide a method for soil deformation analysis based on energy change rate, comprising the following steps: S1: Obtain stress-strain test data of soil samples during shearing; S2: Based on the principle of energy conservation, calculate the rate of energy change under unit shear strain according to the stress-strain test data; S3: Based on the data of energy change rate and shear strain, plot the energy change rate-shear strain relationship curve and identify the shape characteristics of the curve; S4: Based on the state-related dilatation theory model, the energy change rate is correlated with the state-related dilatation parameters of the soil sample to establish an analytical relationship between the energy change rate and the dilatation parameters; S5: Based on the plateau-gradient morphological characteristics of the energy change rate-shear strain relationship curve and the analytical relationship, an explicit constitutive relationship model between the stress ratio and the dilatation parameter is constructed to generate the dynamic energy compensation result between the decrease of deviatoric stress and the work done by dilatation on the soil during the strain softening stage.

[0009] Preferably, S1 includes the following steps: Based on triaxial shear tests of soil, data on axial stress, confining pressure, axial strain, and volumetric strain of soil samples during the shearing process are obtained. Based on these data, shear strain, mean principal stress, and deviatoric stress are calculated to determine the rate of energy change per unit shear strain.

[0010] Preferably, the energy change rate in S2 Calculated using the following formula:

[0011] in, It is a deviatoric stress. For the mean principal stress, For volumetric strain, For shear strain, The rate of change of volumetric strain with shear strain.

[0012] Preferably, the step of plotting the energy change rate-shear strain relationship curve in S3 includes: Normalizing the rate of energy change yields the normalized energy curve:

[0013] Preferably, the step of identifying the morphological features of the curve in S3 includes: Analyze the characteristics of the curve in segments A, B, and C, among which, Section A exhibits a peak-drop pattern, with the curve showing a monotonically increasing trend to a single peak value followed by a monotonically decreasing trend. Furthermore, the absolute values ​​of its first derivative in the increasing and decreasing segments are greater than or equal to a preset threshold, which is used to characterize the abrupt transition of the friction state between soil particles from static friction to dynamic friction. Section B is a horizontal platform shape, the curve shows the characteristics of a platform, and the absolute value of its first derivative remains within a preset threshold range, which is used to characterize the relatively stable stage of energy absorption rate. The C segment exhibits a slow decay pattern, with the curve showing a monotonically decreasing trend. Furthermore, the absolute value of its first derivative in the decreasing segment is greater than or equal to a preset threshold, which is used to characterize the gradual weakening of the energy compensation effect.

[0014] Preferably, in S4, the energy change rate and shear dilatation parameter are established. The analytical relationship between them:

[0015] in, For state parameters, Porosity Critical porosity ratio, The critical stress ratio. This is the unloading coefficient.

[0016] Preferably, in S5, the quasi-constant value of the energy change rate during the plateau phase is used. , construct stress ratio With the shear dilatation parameter Explicit constitutive relation model between them:

[0017] in, Let be a quasi-constant related to the soil state, expressed as .

[0018] Preferably, the explicit constitutive relation model is used to calibrate the dilatation parameters in the soil constitutive model, or as a stress-strain relation module in the soil constitutive model, and is directly used for geotechnical numerical calculations or stability assessments.

[0019] Preferably, in S5, the dynamic energy compensation result between the decrease in deviatoric stress and the work done by shear dilatation in the strain softening stage of the soil is as follows: it is determined that in the strain softening stage, there is a dynamic compensation relationship between the reduction in shear energy consumption caused by the decrease in deviatoric stress and the increase in work done by volume expansion caused by shear dilatation, which makes the rate of change of total energy tend to stabilize.

[0020] Secondly, embodiments of the present invention provide a soil deformation analysis system based on the aforementioned soil deformation analysis method based on energy change rate, comprising: The test data acquisition module is used to acquire stress-strain test data of soil samples during the shearing process; The energy calculation module is used to calculate the rate of energy change under unit shear strain based on the stress-strain test data, according to the principle of energy conservation. The curve plotting and analysis module is used to plot the energy change rate-shear strain relationship curve based on the energy change rate and shear strain data, and to identify the shape characteristics of the curve. The analytical relationship construction module, based on the state-related dilatation theory model, associates the energy change rate with the state-related dilatation parameters of the soil sample to establish an analytical relationship between the energy change rate and the dilatation parameters. The energy compensation analysis module, based on the plateau-gradient morphological characteristics of the energy change rate-shear strain relationship curve and the analytical relationship, constructs an explicit constitutive relationship model between the stress ratio and the dilatation parameter, which is used to generate dynamic energy compensation results between the decrease in deviatoric stress and the work done by dilatation on the soil during the strain softening stage.

[0021] The technical solutions provided in these embodiments of the invention address the problem in the prior art of the difficulty in uniformly describing the strain hardening, softening, and dilatation coupling behavior of soil from an energy perspective. Specific beneficial effects include at least: This invention provides a new analytical perspective. By establishing a stress-strain relationship curve from the perspective of energy change rate, it can comprehensively reflect the coupling effect of stress and strain in all directions during shearing, overcoming the shortcomings of traditional deviatoric stress-strain curves that fail to fully couple volume changes.

[0022] This invention reveals the energy compensation mechanism during the strain softening stage of soil. For the first time, it explicitly proposes and verifies the dynamic energy compensation mechanism between the decrease in deviatoric stress and the work done by dilatation during strain softening, providing a unified explanation of the coupling behavior between strain softening and dilatation from an energy perspective.

[0023] This invention proposes a strategy for identifying the transformation of micro-friction modes. The "peak-fall" characteristic of the normalized energy curve intuitively reflects the abrupt transition of interparticle friction from static friction to kinetic friction, providing new evidence for understanding the micro-mechanism of soil shear initiation.

[0024] This invention supports the construction of soil constitutive models. Based on the "plateau-gradient" stability characteristics of energy change rate, it can be used as an internal variable or constraint condition to construct soil constitutive models, simplifying parameter calibration and enhancing the physical meaning of the model. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0026] Figure 1This is a flowchart of the soil deformation analysis method based on energy change rate provided in the embodiments of the present invention; Figure 2 This is a schematic diagram illustrating the energy input per unit volume of soil to external force work provided in this embodiment of the invention. Figure 3 This is a standard sand particle size distribution curve provided in the embodiments of the present invention; Figure 4 This is a schematic diagram of the results of a consolidated drained triaxial test of saturated standard sand provided in an embodiment of the present invention; Figure 5 The strain-hardening state provided in the embodiments of the present invention , and Schematic diagram of the relationship between shear strain and shear strain; Figure 6 The strain-hardening state provided in the embodiments of the present invention , and Schematic diagram of the relationship between shear strain and shear strain; Figure 7 This is a schematic diagram showing the relationship between energy parameters and shear strain during strain softening under different confining pressures, as provided in an embodiment of the present invention. Figure 8 The normalized energy change rate provided in the embodiments of the present invention Schematic diagram of the relationship between shear strain and shear strain; Figure 9 The shearing process provided in the embodiments of the present invention With shear strain A diagram illustrating the relationship between the two. Detailed Implementation

[0027] 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 embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] This invention discloses a method for soil deformation analysis based on the rate of energy change, such as... Figure 1 As shown, Figure 1 As shown, it includes the following steps: S1: Obtain stress-strain test data of soil samples during shearing; S2: Based on the principle of energy conservation, calculate the rate of energy change under unit shear strain according to stress-strain test data; S3: Based on the data of energy change rate and shear strain, plot the energy change rate-shear strain relationship curve and identify the shape characteristics of the curve; S4: Based on the state-related dilatation theory model, the energy change rate is correlated with the state-related dilatation parameters of the soil sample to establish an analytical relationship between the energy change rate and the dilatation parameters; S5: Based on the plateau-gradient morphological characteristics and analytical relationship of the energy change rate-shear strain relationship curve, an explicit constitutive relationship model between stress ratio and dilatation parameter is constructed to generate dynamic energy compensation results between the decrease of deviatoric stress and the work done by dilatation on the soil during the strain softening stage.

[0029] In one embodiment, S1 includes the following steps: Based on triaxial shear tests of soil, the axial stress of the soil sample during the shearing process is obtained. Confining pressure Axial strain and volumetric strain The data was used to calculate the spherical stress (mean principal stress). eccentric stress Shear strain It is used to calculate the rate of change of energy under unit shear strain.

[0030] In one embodiment, the rate of energy change in S2 Calculated using the following formula:

[0031] in, It is a deviatoric stress. For the mean principal stress, For volumetric strain, For shear strain, The rate of change of volumetric strain with shear strain.

[0032] In one embodiment, the energy change rate-shear strain relationship curve is plotted in S3. The steps for (curve) include: Normalizing the rate of energy change yields the normalized energy curve:

[0033] Plot the relationship between energy change rate and shear strain to analyze the state of the curve during the strain hardening and softening stages.

[0034] In one embodiment, the step of identifying the morphological features of the curve in S3 includes: Analyze the characteristics of the curve in segments A, B, and C, among which, Section A exhibits a peak-drop pattern, with the curve showing a monotonically increasing trend to a single peak value followed by a monotonically decreasing trend. Furthermore, the absolute values ​​of its first derivative in the increasing and decreasing segments are greater than or equal to a preset threshold, which is used to characterize the abrupt transition of the friction state between soil particles from static friction to dynamic friction. Section B is a horizontal platform shape, the curve shows the characteristics of a platform, and the absolute value of its first derivative remains within a preset threshold range, which is used to characterize the relatively stable stage of energy absorption rate. The C segment exhibits a slow decay pattern, with the curve showing a monotonically decreasing trend. Furthermore, the absolute value of its first derivative in the decreasing segment is greater than or equal to a preset threshold, which is used to characterize the gradual weakening of the energy compensation effect.

[0035] It should be noted that soil stability is assessed based on characteristic morphology: when the curve shows... When the curve shows the characteristics of a platform, it is determined that the soil is in a quasi-equilibrium state with stable energy dissipation; when the curve shows a gradual descent, it is determined that the soil stability is decreasing and is transitioning to a positive residual state.

[0036] In one embodiment, S4 is based on the Cambridge model, the Rowe dilatation model, and state-dependent dilatation theory:

[0037]

[0038]

[0039]

[0040] in, The unloading coefficient (the unloading curve at) v‐p′ (slope on the plane) Porosity This represents the stress ratio under critical conditions. For dilatation parameters ( , (Critical void ratio). The elastic component of shear strain is not considered. Then, substitute equations (2), (3), (4), and (5) into equation (1) to establish the rate of energy change. With dilatation parameters The analytical relationship between them is used to explain the evolution mechanism of the energy curve:

[0041] in, For state parameters, Porosity Critical porosity ratio, The critical stress ratio. This is the unloading coefficient.

[0042] Equation (6) uses the dilatation parameter The two energy mechanisms of shear friction and volume change are dynamically coupled: Indicates the dilatation parameter Adjusted shear energy dissipation rate; This represents the power of the volume change caused by dilatation; This represents the energy rate corresponding to the change in elastic volume. It should be noted that the role of equation (6) is to: utilize the measurable macroscopic energy curve to determine the state-dependent dilatation function, which is the most crucial and difficult-to-determine function in the constitutive model. This paper presents a novel and direct data-driven approach that enhances the physical objectivity of model parameters.

[0043] In one embodiment, S5, based on the rate of energy change The "plateau-gradient" stability characteristic exhibited in both the hardening and softening stages allows the energy absorption rate to be used as a stability index or internal state variable when constructing the constitutive model. From equation (6) and the observed "plateau" characteristic, during the shear failure stage, This indicates that the energy rate corresponding to the elastic volume change is negligible, and the stress ratio is constructed. With dilatation parameters Explicit constitutive relation model between them:

[0044] in, Let be a quasi-constant related to the soil state, expressed as .

[0045] It should be noted that the function of equation (7) is to transform the stable phenomenon of the energy absorption rate plateau discovered in this invention into a highly simplified explicit constitutive relation. This relation can be directly used in geotechnical engineering numerical analysis software as a core module for calculating stress response, or as a practical formula for rapid mechanical evaluation, thereby achieving the fundamental purpose of simplifying the model, improving computational efficiency, and serving engineering practice.

[0046] In one embodiment, the explicit constitutive relation model is used to calibrate the dilatation parameters in the soil constitutive model, or as a stress-strain relation module in the soil constitutive model, and can be directly used for geotechnical numerical calculations or stability assessments.

[0047] In one embodiment, S5, the dynamic energy compensation result between the decrease in deviatoric stress and the work done by shear dilatation in the strain softening stage of the soil is as follows: it is determined that in the strain softening stage, there is a dynamic compensation relationship between the reduction in shear energy consumption caused by the decrease in deviatoric stress and the increase in work done by volume expansion caused by shear dilatation, which makes the rate of change of total energy tend to stabilize.

[0048] Based on the same inventive concept, embodiments of the present invention also provide a soil deformation analysis system according to a soil deformation analysis method based on energy change rate. The technical features of the system are also applicable to the execution steps of the soil deformation analysis method based on energy change rate. This includes: The test data acquisition module is used to acquire stress-strain test data of soil samples during the shearing process; The energy calculation module is used to calculate the rate of energy change under unit shear strain based on the principle of energy conservation and stress-strain test data. The curve plotting and analysis module is used to plot the energy change rate-shear strain relationship curve based on the data of energy change rate and shear strain, and to identify the shape characteristics of the curve; The analytical relationship construction module, based on the state-dependent dilatation theory model, associates the energy change rate with the state-dependent dilatation parameters of the soil sample to establish an analytical relationship between the energy change rate and the dilatation parameters. The energy compensation analysis module, based on the platform-gradient morphological characteristics and analytical relationship of the energy change rate-shear strain relationship curve, constructs an explicit constitutive relationship model between stress ratio and dilatation parameter, which is used to generate dynamic energy compensation results between the decrease of deviatoric stress and the work done by dilatation on the soil during the strain softening stage.

[0049] In one embodiment, the curve plotting and analysis module is also used for plotting... curve, The curve and its corresponding normalized curve are obtained, and the curve feature parameters are extracted.

[0050] In one embodiment, a constitutive modeling support module is also included, which is used to calibrate dilatation parameters based on energy curve characteristics to support the construction of an energy-dilatation coupled constitutive model.

[0051] It should be noted that the dynamic energy compensation results revealed by the explicit constitutive relationship model between the stress ratio and the dilatation parameter in the embodiments of the present invention can be used in various technical scenarios as follows: 1. Development and parameter calibration of soil constitutive models; 2. Material model verification in numerical simulation of geotechnical engineering; 3. Research and teaching demonstration of soil failure mechanisms; 4. Soil deformation and stability assessment in engineering practice; 5. Soil deformation prediction and monitoring early warning in geological disaster analysis.

[0052] Based on the same inventive concept, embodiments of the present invention also provide a computer-readable storage medium having a computer program stored thereon, wherein the program, when executed by a processor, implements the steps of the above-described method for soil deformation analysis based on energy change rate.

[0053] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited to the following embodiments.

[0054] Example 1: Energy change rate analysis of saturated standard sand.

[0055] 1. Sample Preparation and Testing: Fujian standard sand was selected, and its physical parameters are shown in Table 1. The relative density of the sample was prepared. Saturated sand samples with concentrations of 0.2, 0.5, and 0.8 were prepared using an underwater sedimentation method. Consolidated drained triaxial compression tests were conducted under confining pressures of 100 kPa, 200 kPa, 300 kPa, and 400 kPa, with a shear rate of 0.01 mm / min. Figure 2 As shown, the trend of energy change per unit volume of soil due to external force work is as follows: Figure 3 The figure shows the particle size distribution curve of standard sand.

[0056] Table 1 Physical parameters of standard sand

[0057] 2. Data Acquisition and Processing: Real-time acquisition of axial stress. Confining pressure Axial strain and volumetric strain Calculate the spherical stress (mean principal stress) using continuous data. eccentric stress Shear strain ;like Figure 4 As shown, Figure (a) is the deviatoric stress-principal strain curve, and Figure (b) is the volumetric strain-principal strain curve.

[0058] 3. Calculation of energy change rate: Approximate calculation using the central difference method. Substitute into the formula to calculate .

[0059] 4. Curve Plotting and Analysis: Plotting curves as follows... Figure 5 , Figure 6 The energy curve shown. Figure 5 In the figure, (a) shows the relative density. hour , and The relationship between shear strain and density is shown in Figure (b), which represents the relative density. hour 、 and Relationship between shear strain and shear strain. Figure 6 In the figure, (a) shows the relative density. Confining pressure CP When it is 100 kPa , and The relationship between shear strain and density is shown in Figure (b), which represents the relative density. When the confining pressure CP is 300 kPa 、 and The relationship between strain hardening and strain softening is shown. Both exhibited a "plateau-gradual decline" characteristic, while Curve descent and The curve rises in an inverse symmetric manner. Figure 7 This indicates the existence of dynamic energy compensation.

[0060] 5. Normalization analysis: plotting Curves, such as Figure 7 As shown, Figure (a) shows the relative density. Confining pressure CP Figure (a) shows the relationship between energy parameters and shear strain at 100 kPa; Figure (b) shows the relative density. Confining pressure CP Figure (c) shows the relationship between energy parameters and shear strain at 200 kPa; Figure (c) shows the relative density. Confining pressure CP Figure (d) shows the relationship between energy parameters and shear strain at 300 kPa; Figure (d) shows the relative density. Confining pressure CP The relationship between energy parameters and shear strain at 400 kPa is shown. Figure 8 As shown, Figure (a) shows the relative density. Figure (b) shows the relationship between the normalized rate of change of energy and shear strain at a strain hardening factor of 0.5 (strain hardening); Figure (b) shows the relative density. The graph shows the relationship between the normalized rate of change of energy and shear strain when the strain coefficient is 0.8 (strain softening). It can be seen that section A is a peak-drop (frictional abrupt change), section B is a horizontal plateau (energy stability), and section C is a gradual decrease (compensation attenuation).

[0061] 6. right Impact analysis: such as Figure 9 As shown, this is the process of shearing. With shear strain The relationship. During the shear failure stage (deviatoric stress) (after the peak) The value fluctuates slightly around zero (for dense sand, the unloading coefficient) During calculation, take =0.006), its mean absolute value is less than 0.04 (100kPa), the linear fitting coefficient is extremely small (less than 0.02%), and (in Table 1) This indicates that during the shear failure stage, in equation (6) The value is close to 0, and significantly smaller in magnitude than the same unit. Its effect on The impact can be approximated as negligible, and the calculation data can be referenced. Figure 5 , Figure 6 And Table 2.

[0062] 7. In relative density shearing Containment pressure Under these conditions, the shear strain during the triaxial test of Fujian standard sand Body strain Mean stress eccentric stress Stress ratio / Energy change rate / , · / , and / The experimental data are detailed in Table 2.

[0063] Table 2 Example of test data ( )

[0064] Note: Shear strain in the table With body strain The unit is %; average stress eccentric stress Energy change rate / , · / and The unit is 100 kPa; stress ratio / and / It is a dimensionless coefficient.

[0065] 8. Mechanism Explanation: Combining state-related dilatation theory, analysis shows that in the main shear stage, the elastic term has a weak influence, and the energy change is mainly dominated by the coupling of plastic dilatation and deviatoric stress. The dilatation coefficient... The evolution of energy compensation is the core of energy compensation.

[0066] 9. Application of this model: Based on The platform characteristics allow for the establishment of stress ratios. With dilatation parameters The explicit relationship between them (Equation 7) is used to calibrate the dilatation parameters and construct an energy-dilatation coupled constitutive model.

[0067] Example 2: System Implementation.

[0068] This embodiment provides a soil stress-strain analysis system, including: 1. Hardware components: triaxial testing machine, data acquisition card, computer; 2. Software component: Program modules developed based on Python or MATLAB to implement functions such as data import, energy calculation, curve plotting, feature extraction, and mechanism analysis; 3. User interface: Provides interactive functions such as parameter input, curve display, result export, and report generation.

[0069] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0070] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for soil deformation analysis based on energy change rate, characterized in that, Includes the following steps: S1: Obtain stress-strain test data of soil samples during shearing; S2: Based on the principle of energy conservation, calculate the rate of energy change under unit shear strain according to the stress-strain test data; S3: Based on the data of energy change rate and shear strain, plot the energy change rate-shear strain relationship curve and identify the shape characteristics of the curve; S4: Based on the state-related dilatation theory model, the energy change rate is correlated with the state-related dilatation parameters of the soil sample to establish an analytical relationship between the energy change rate and the dilatation parameters; S5: Based on the plateau-gradient morphological characteristics of the energy change rate-shear strain relationship curve and the analytical relationship, an explicit constitutive relationship model between the stress ratio and the dilatation parameter is constructed to generate the dynamic energy compensation result between the decrease of deviatoric stress and the work done by dilatation on the soil during the strain softening stage.

2. The soil deformation analysis method based on energy change rate as described in claim 1, characterized in that, S1 includes the following steps: Based on triaxial shear tests of soil, data on axial stress, confining pressure, axial strain, and volumetric strain of soil samples during the shearing process are obtained. Based on these data, shear strain, mean principal stress, and deviatoric stress are calculated to determine the rate of energy change per unit shear strain.

3. The soil deformation analysis method based on energy change rate as described in claim 1, characterized in that, The rate of energy change described in S2 Calculated using the following formula: in, It is a deviatoric stress. For the mean principal stress, For volumetric strain, For shear strain, The rate of change of volumetric strain with shear strain.

4. The soil deformation analysis method based on energy change rate as described in claim 3, characterized in that, The steps for plotting the energy change rate-shear strain relationship curve in S3 include: Normalizing the rate of energy change yields the normalized energy curve: 。 5. The soil deformation analysis method based on energy change rate as described in claim 1, characterized in that, The steps for identifying the morphological features of a curve in S3 include: Analyze the characteristics of the curve in segments A, B, and C, among which, Section A exhibits a peak-drop pattern, with the curve showing a monotonically increasing trend to a single peak value followed by a monotonically decreasing trend. Furthermore, the absolute values ​​of its first derivative in the increasing and decreasing segments are greater than or equal to a preset threshold, which is used to characterize the abrupt transition of the friction state between soil particles from static friction to dynamic friction. Section B is a horizontal platform shape, the curve shows the characteristics of a platform, and the absolute value of its first derivative remains within a preset threshold range, which is used to characterize the relatively stable stage of energy absorption rate. The C segment exhibits a slow decay pattern, with the curve showing a monotonically decreasing trend. Furthermore, the absolute value of its first derivative in the decreasing segment is greater than or equal to a preset threshold, which is used to characterize the gradual weakening of the energy compensation effect.

6. The soil deformation analysis method based on energy change rate as described in claim 3, characterized in that, In S4, the energy change rate and dilatation parameter are established. The analytical relationship between them: in, For state parameters, Porosity Critical porosity ratio, The critical stress ratio. This is the unloading coefficient.

7. The soil deformation analysis method based on energy change rate as described in claim 6, characterized in that, In S5, the quasi-constant value of the rate of energy change during the plateau phase is used. , construct stress ratio With the shear dilatation parameter Explicit constitutive relation model between them: in, Let be a quasi-constant related to the soil state, expressed as .

8. The soil deformation analysis method based on energy change rate as described in claim 1, characterized in that, The explicit constitutive relation model is used to calibrate the dilatation parameters in the soil constitutive model, or as a stress-strain relation module in the soil constitutive model, and can be directly used for numerical calculations or stability assessments in geotechnical engineering.

9. The soil deformation analysis method based on energy change rate as described in claim 1, characterized in that, In S5, the dynamic energy compensation result between the decrease in deviatoric stress and the work done by shear dilatation in the strain softening stage of the soil is as follows: It is determined that in the strain softening stage, there is a dynamic compensation relationship between the reduction in shear energy consumption caused by the decrease in deviatoric stress and the increase in work done by volume expansion caused by shear dilatation, which makes the rate of change of total energy tend to stabilize.

10. A soil deformation analysis system based on the energy change rate method as described in any one of claims 1 to 9, characterized in that, include: The test data acquisition module is used to acquire stress-strain test data of soil samples during the shearing process; The energy calculation module is used to calculate the rate of energy change under unit shear strain based on the stress-strain test data, according to the principle of energy conservation. The curve plotting and analysis module is used to plot the energy change rate-shear strain relationship curve based on the energy change rate and shear strain data, and to identify the shape characteristics of the curve. The analytical relationship construction module, based on the state-related dilatation theory model, associates the energy change rate with the state-related dilatation parameters of the soil sample to establish an analytical relationship between the energy change rate and the dilatation parameters. The energy compensation analysis module, based on the plateau-gradient morphological characteristics of the energy change rate-shear strain relationship curve and the analytical relationship, constructs an explicit constitutive relationship model between the stress ratio and the dilatation parameter, which is used to generate dynamic energy compensation results between the decrease in deviatoric stress and the work done by dilatation on the soil during the strain softening stage.

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