Improved westergaard body modeling method and system for hard-soft rock interface under ring shear creep test

Abstract

This invention provides an improved Westpuria modeling method and system for hard-soft rock interfaces under circumferential shear creep tests, relating to the fields of geotechnical engineering and geological disaster early warning technology. It aims to solve the problem that traditional Westpuria models cannot accurately describe the nonlinear creep evolution of hard-soft rock interface under circumferential shear conditions. The method first conducts circumferential shear creep tests on the hard-soft rock interface to obtain curve data of the entire circumferential shear creep process; preprocesses the data and extracts creep stage characteristics; introduces nonlinear creep components based on the traditional Westpuria model to construct an improved Westpuria constitutive model; performs parameter identification and fitting evaluation of the model based on the preprocessed data; and then applies the model to deformation analysis and engineering prediction of the hard-soft rock interface, enhancing the ability to describe the nonlinear characteristics of the entire process of interface decay, steady-state, and accelerated creep.

Description

Technical Field

[0001] This invention belongs to the field of geotechnical engineering and geological disaster early warning technology, specifically relating to a ring shear creep. An improved modeling method and system for the Xiyuan body at the interface between hard and soft rocks was tested. Background Technology

[0002] In geotechnical engineering, the interface between hard and soft rock layers is a key weak point that controls the long-term stability of slopes, tunnels and foundations, and its creep characteristics directly affect the safe service life of the engineering structure.

[0003] Currently, models such as Kelvin, Maxwell, Burgers, and Westproton are commonly used to describe the creep behavior of rock masses and structural surfaces. Among them, the Westproton model can better characterize instantaneous deformation, decaying creep, and steady-state creep, and is widely used.

[0004] However, existing models are mostly designed for intact rock masses or general structural surfaces, making it difficult to accurately reflect the nonlinear creep characteristics of the contact interface between hard and soft rock layers under circumferential shear conditions. In particular, they still have shortcomings in terms of later nonlinear deformation evolution, parameter identification, and engineering applicability. Summary of the Invention

[0005] The purpose of this invention is to provide an improved method and system for modeling the interface between hard and soft rock layers under ring shear creep tests, which solves the problem that traditional Xiyuan body models cannot accurately describe the nonlinear creep evolution of the interface between hard and soft rock layers under ring shear conditions.

[0006] To achieve the above objectives, this invention provides an improved method for modeling the Xiyuan body at the interface between hard and soft rock under a ring shear creep test, the method comprising: S1: Conduct ring shear creep tests on the contact interface between hard and soft rock layers to obtain the full-process curve data of ring shear creep. S2: Preprocess the entire process curve data of the ring shear creep and extract the creep stage features; S3: Based on the traditional Westprone model, an improved Westprone constitutive model is constructed by introducing a nonlinear creep component. S4: Based on the preprocessed circumferential creep curve data, parameter identification and fitting evaluation are performed on the improved Westprobe constitutive model; S5: The improved constitutive model of the West Prototype, after parameter identification and fitting evaluation, is applied to the deformation analysis and engineering prediction of the contact interface between hard and soft rocks.

[0007] Preferably, step S1 includes: The hard and soft rock were reshaped into a ring sample. The hard rock layer and the soft rock layer were combined to form the contact interface between the hard and soft rock layers. The ring sample was then subjected to a normal load and consolidated using a fully automatic servo dynamic control ring shearing device. A single-stage ring shear test was conducted by applying torque at a preset rate until the ring specimen failed shear, and the shear failure torque data was recorded. The shear failure torque data were applied in stages at 50%, 60%, 70%, 80%, 90%, and 95%, with each stress level applied for 6 hours, to obtain the full-process curve data of circumferential shear creep under different normal stresses.

[0008] Preferably, the preprocessing in step S2 includes: based on the Boltzmann superposition principle, decomposing the full-process circumferential shear creep curve data obtained under graded loading into single-stage creep curves under different shear stress levels.

[0009] Preferably, step S3 includes: Based on the traditional Westprime model composed of an ideal viscoplastic body and a generalized Kelvin body, a nonlinear creep component is introduced. The nonlinear creep component includes the contact interface yield strength, the viscosity coefficient of the nonlinear element, the nonlinear creep time, and the nonlinear creep parameter, thus obtaining an improved Westprime constitutive model with the nonlinear creep component.

[0010] Preferably, in step S3, the constitutive equation of the traditional Westproton model is: (1); in, In response, For stress, For time, and These are the elastic moduli in Hookean and Kelvin bodies, respectively. and These are the viscosity coefficients in the generalized Kelvin and the ideal viscoplastic body, respectively. The contact interface yield strength; The constitutive equation for the nonlinear creep component is: (2); in, The contact interface yield strength, The viscosity coefficient of a nonlinear element. To be related to nonlinear creep parameters The corresponding nonlinear creep time, This is a nonlinear creep parameter.

[0011] The improved constitutive model formula for the Westproton obtained after introducing the nonlinear creep component is as follows: (3); in, In response, For stress, For time, and These are the elastic moduli in Hookean and Kelvin bodies, respectively. and These are the viscosity coefficients in the generalized Kelvin and the ideal viscoplastic body, respectively. The contact interface yield strength, The viscosity coefficient of a nonlinear element. To be related to nonlinear creep parameters The corresponding nonlinear creep time, This is a nonlinear creep parameter.

[0012] Preferably, the parameter identification and fitting analysis of the improved Westprobe constitutive model in step S4 includes: Nonlinear fitting software was used to identify parameters and evaluate the fit of the improved constitutive model of the West Primordial Body to obtain the goodness of fit. The improved constitutive model formula for the Westprobe, after parameter identification and fitting evaluation, is as follows: (4); in, For shear strain, For the current time, To accelerate the creep characteristic time, α= β is the reciprocal of the instantaneous elastic shear modulus. , is the reciprocal of the delayed elastic shear modulus. , is the reciprocal of the first viscosity coefficient. , is the reciprocal of the steady-state viscosity coefficient. , is the nonlinear acceleration creep coefficient. To accelerate creep time factor.

[0013] Preferably, step S5 includes: embedding the improved constitutive model of the West Prototype after parameter identification and fitting evaluation into numerical analysis software to predict the creep deformation of the contact interface between hard and soft rock layers under long-term load; and judging whether the contact interface between hard and soft rock layers has entered the creep stage based on the prediction results, so as to assess the long-term stability of geotechnical engineering and determine the timing of reinforcement treatment.

[0014] Compared with existing technologies, the improved Westland modeling method for hard and soft rock interfaces provided by this invention has the following advantages: By introducing nonlinear creep components into the traditional Westland model to construct an improved Westland constitutive model, the ability to characterize the nonlinear time-dependent deformation law of the contact interface between hard and soft rock layers is significantly improved. At the same time, by combining the test data of the circumferential shear creep test for parameter identification and fitting analysis, the accurate matching between the model parameters and the actual mechanical response is achieved, effectively improving the fitting accuracy of the test data. This enhances the ability to describe the nonlinear characteristics of the entire process of contact interface decay, steady state, and accelerated creep, and ultimately provides reliable technical support for the long-term deformation prediction of the contact interface between hard and soft rock layers and related geotechnical engineering stability analysis.

[0015] This invention also provides an improved modeling system for the interface between hard and soft rock under ring shear creep tests, the system comprising: The test data acquisition module is used to conduct ring shear creep tests on the contact interface between hard and soft rock layers and obtain the full-process curve data of ring shear creep. The data preprocessing and feature extraction module is used to preprocess the entire process curve data of the ring shear creep and extract the creep stage features; The constitutive model construction module is used to construct an improved constitutive model of Westpurus based on the traditional Westpurus model by introducing nonlinear creep components. The parameter identification and fitting evaluation module is used to identify and evaluate the parameters of the improved Westprobe constitutive model based on the preprocessed circumferential creep curve data. The engineering application module is used to apply the improved constitutive model of the West Prototype, after parameter identification and fitting evaluation, to the deformation analysis and engineering prediction of the contact interface between hard and soft rocks.

[0016] Compared with the prior art, the improved Xiyuan body modeling system for hard and soft rock interface under ring shear creep test provided by the embodiments of the present invention has the same beneficial effects as the improved Xiyuan body modeling method for hard and soft rock interface under ring shear creep test provided by the above technical solution, and will not be repeated here.

[0017] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0018] 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 some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 A flowchart illustrating an improved method for modeling the interface between hard and soft rock under a ring shear creep test, provided by an embodiment of the present invention, is shown. Figure 2 A schematic diagram of the annular sample provided in an embodiment of the present invention is shown; Figure 3 This invention provides a schematic diagram of the entire process curves of ring shear creep of a ring specimen under different normal stresses (397.89 kPa, 596.83 kPa and 795.77 kPa) obtained from ring shear test data. Figure 4 The embodiments of the present invention provide a method for... Figure 3 A schematic diagram of the entire process of circumferential shear creep under a stress of 397.89 kPa after graded treatment; Figure 5 A schematic diagram of the improved Westprobe constitutive model with the introduction of a nonlinear creep component provided in an embodiment of the present invention is shown. Figure 6 The diagram shows a schematic of fitting the improved Westprime constitutive model of a nonlinear creep component to the strain-time curve under a stress of 397.89 kPa based on graded processing, provided by an embodiment of the present invention. Detailed Implementation

[0020] 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.

[0021] In this embodiment, "multiple" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. Words such as "exemplary" or "for example" are used to indicate examples, illustrations, or explanations, intended to present related concepts in a specific manner, and should not be construed as superior or more advantageous than other embodiments or designs.

[0022] This invention provides an improved method for modeling the interface between hard and soft rock in the Xiyuan body under ring shear creep tests. Figure 1 This diagram illustrates a flowchart of an improved method for modeling the Xiyuan body at the interface between hard and soft rock under a ring shear creep test, as provided in an embodiment of the present invention. Figure 1 As shown, the method includes: S1: Conduct ring shear creep tests on the interface between hard and soft rock layers to obtain the full-process curve data of ring shear creep.

[0023] This step forms the basis of the entire modeling method. Its core is to obtain real creep response data of the contact interface between hard and soft rock layers under different working conditions through standardized ring shear creep tests, providing a reliable basis for subsequent data processing, model construction and parameter identification.

[0024] The specific implementation process is as follows: 1. Sample Preparation: The original rock of an alternating hard-upper and soft-lower layered rock mass was selected. After crushing, the original rock was reshaped into ring-shaped samples. The reshaping process was strictly controlled according to the actual contact state between the hard and soft rock layers in the engineering project to ensure that the mechanical properties of the reshaped samples were consistent with the characteristics of the original rock interface. The reshaped samples were then processed as follows: Figure 2 The annular sample shown has an outer diameter of Ø100 mm, an inner diameter of Ø60 mm, and a height of 20 mm. This ensures that the sample contact interface is intact, undamaged, and free of impurities, and closely matches the actual contact state of hard and soft rock layers in the engineering project.

[0025] 2. Test equipment: The ZSHJ-3 fully automatic servo dynamic control ring shear apparatus is used. This equipment can accurately apply vertical consolidation pressure and simulate the actual confining pressure environment of rock strata under conditions without lateral deformation. It meets the requirements of both drained and non-drained test conditions, ensuring that the test process is consistent with the actual stress environment of the project.

[0026] 3. Experimental Procedure: First, a ZSHJ-3 fully automatic servo-controlled ring shear tester was used to apply different normal loads to annular specimens with an outer diameter of Ø100 mm × inner diameter of Ø60 mm × height of 20 mm. Each load level lasted for 120 minutes to ensure complete consolidation of the specimens and simulate the actual confining pressure environment of the rock strata. After the specimens were consolidated and the normal stress stabilized, a conventional single-stage ring shear test was conducted by applying torque at a certain rate (data acquisition frequency: 1 s / time) until the annular specimens experienced shear failure. The shear failure torque data of the annular specimens was recorded, which is the peak shear strength. This data serves as the core basis for the subsequent creep test with graded loading, specifically set at 50%, 60%, 70%, 80%, 90%, and 95% of the shear failure torque. Afterward, annular specimens of the same specifications underwent the same consolidation treatment. Based on the previously measured peak shear strength, different stress levels were set for the creep test, with each stress level lasting for 6 hours, and the ring shear creep test was carried out. During the test, horizontal torsional shear was performed under drained or non-drained conditions according to the design requirements to ensure the stability of each stress loading process until the specimen completed the entire creep process (covering the three complete stages of decay creep, steady-state creep, and accelerated creep), so as to avoid incomplete data due to stopping the test midway.

[0027] 4. Data Acquisition: During the experiment, the built-in data acquisition system of the ZSHJ-3 ring shear apparatus was used to collect shear strain variation data over time at a frequency of 1 second, ensuring the continuity and timeliness of the data. Simultaneously, combined with the specimen roughness parameters, normal stresses for different roughnesses were plotted, such as... Figure 3 The curves shown are the full-process shear creep curves at the interface between hard and soft rock layers under conditions of 397.89 kPa, 596.83 kPa, and 795.77 kPa, i.e., shear strain-time curves. Key test parameters such as normal stress, shear stress, consolidation time, test conditions (drained / undrained), stress values ​​at each loading level, and loading duration were recorded simultaneously during the test to ensure the integrity and accuracy of the data, laying the foundation for subsequent data preprocessing and parameter identification.

[0028] S2: Preprocess the entire process curve data of the ring shear creep and extract the creep stage features.

[0029] It should be noted that the core purpose of this step is to remove interference information from the experimental data, optimize data quality, and extract characteristic parameters of each stage of creep. This provides accurate feature basis for the subsequent construction of improved models and parameter identification, solves the problems of discreteness and error in the original experimental data, and avoids interference data from affecting the model fitting accuracy.

[0030] The specific implementation process is as follows: 1. Data Preprocessing: Since the ring shear creep test is conducted using a graded loading method, in order to accurately obtain the independent creep response of the contact interface under different shear stress levels, the Boltzmann superposition principle is used to grade the collected ring shear creep curve data. The total creep deformation under multiple stress levels can be regarded as the superposition of creep deformation caused by the individual action of each stress increment. Therefore, the total strain curve obtained by continuous graded loading is decomposed into single-stage creep curves under different shear stress levels, thereby eliminating the influence of the previous loading history on the subsequent creep curve analysis. Figure 4 The diagram shows a graded strain-time curve under a stress of 397.89 kPa. Figure 4 As shown, using the Boltzmann superposition principle, for Figure 3 The entire process curve of ring shear creep at the normal stress (397.89 kPa) was processed to obtain the staged loading creep curve, as shown below. Figure 4 As shown, 0.5Tp refers to half of the shear stress at which the specimen fails.

[0031] The grading standard is set in conjunction with the test shear stress level, and creep data under different shear stresses are processed segment by segment. Discrete data points caused by equipment errors and environmental interference (such as temperature and humidity fluctuations) during the test are removed. Curve fluctuations are eliminated through data smoothing algorithms to ensure the continuity and reliability of the data. At the same time, the average total creep strain under each working condition is calculated to reduce the impact of single test errors on subsequent analysis and ensure that the preprocessed data can truly reflect the creep characteristics of the contact interface between hard and soft rock layers.

[0032] 2. Creep Stage Feature Extraction: Based on the pre-processed circumferential shear creep curve, the three core stages of creep at the interface between hard and soft rock strata (decaying creep stage, steady-state creep stage, and accelerated creep stage) are identified, and the time range of each stage is precisely defined. Key characteristic parameters for each stage are extracted, including the strain decay rate (the law of change with time) in the decaying creep stage, the constant creep rate (the rate at which shear strain changes uniformly with time) in the steady-state creep stage, and the strain growth rate (the law of increasing with time) in the accelerated creep stage. Simultaneously, the differences in characteristic parameters corresponding to different normal stresses and different sample roughnesses are recorded in detail, clarifying the influence of normal stress and roughness on creep characteristics, providing a targeted basis for subsequent model fitting and parameter matching.

[0033] S3: Based on the traditional Westproton model, an improved Westproton constitutive model is constructed by introducing a nonlinear creep component.

[0034] It should be noted that this step is the core innovation of the present invention, which aims to solve the problem that the traditional West Prototype model is insufficient in characterizing the accelerated creep stage of the contact interface between hard and soft rock layers. In order to better simulate the nonlinear accelerated creep stage in the experiment, a nonlinear creep component is introduced to optimize the model structure and improve the model's ability to describe nonlinear creep characteristics, thus breaking through the limitation of existing models that can only adapt to complete rock masses or general structural surfaces and are difficult to adapt to the contact interface between hard and soft rock layers.

[0035] The specific implementation process is as follows: 1. Clarify the limitations of the traditional Westprime model: As shown in equation (1), this is the constitutive equation of the traditional Westprime model. (1); in, In response, For stress, For time, and These are the elastic moduli in Hookean and Kelvin bodies, respectively. and These are the viscosity coefficients in the generalized Kelvin and the ideal viscoplastic body, respectively. The contact interface yield strength.

[0036] Traditional Westproton models can fit the decay creep and steady-state creep stages well and accurately reflect the creep laws of these two stages. However, they are not accurate enough in fitting the nonlinear accelerated creep stage of the hard-soft rock interface under shear stress. They cannot accurately reflect the evolution of nonlinear deformation in the later stage and cannot meet the engineering requirements for long-term deformation prediction of the hard-soft rock interface. Therefore, it is necessary to introduce nonlinear creep components for optimization and improvement.

[0037] 2. Introduction of nonlinear creep component: This component is specifically designed for the nonlinear accelerated creep characteristics of the contact interface between hard and soft rock layers. It contains four core parameters, namely the contact interface yield strength, the viscosity coefficient of the nonlinear element, the nonlinear accelerated creep time, and the nonlinear accelerated creep parameter. Its constitutive equation is shown in equation (2). (2); in, The contact interface yield strength, The viscosity coefficient of a nonlinear element. To be related to nonlinear creep parameters The corresponding nonlinear creep time, These are nonlinear creep parameters. The nonlinear creep component can accurately characterize the nonlinear accelerated creep behavior when the shear stress exceeds the yield strength of the contact interface, thus overcoming the core shortcomings of traditional models.

[0038] 3. Constructing an improved constitutive model of Westprone: The nonlinear creep component is fused with the traditional Westprone model to obtain an improved constitutive model of Westprone containing the nonlinear creep component.

[0039] Figure 5 A schematic diagram of the improved Westprobe constitutive model with the introduction of a nonlinear creep component provided in an embodiment of the present invention is shown, as follows: Figure 5 As shown, it is composed of a generalized Kelvin volume and a nonlinear creep component. Equation (3) is the formula for the improved constitutive model of the Westprobe obtained after introducing a nonlinear creep component. (3); in, In response, For stress, For time, and These are the elastic moduli in Hookean and Kelvin bodies, respectively. and These are the viscosity coefficients in the generalized Kelvin and the ideal viscoplastic body, respectively. The contact interface yield strength, The viscosity coefficient of a nonlinear element. To be related to nonlinear creep parameters The corresponding nonlinear creep time, This is a nonlinear creep parameter.

[0040] S4: Based on the preprocessed circumferential creep curve data, parameter identification and fitting evaluation are performed on the improved Westprobe constitutive model.

[0041] It should be noted that the parameter identification and fitting analysis of the improved Westprime constitutive model described in step S4 includes: using nonlinear fitting software to identify and evaluate the parameters of the improved Westprime constitutive model and obtain the goodness of fit; the formula for the improved Westprime constitutive model after parameter identification and fitting evaluation is as follows: (4); in, For shear strain, For the current time, To accelerate the creep characteristic time, α= β is the reciprocal of the instantaneous elastic shear modulus. , is the reciprocal of the delayed elastic shear modulus. , is the reciprocal of the first viscosity coefficient. , is the reciprocal of the steady-state viscosity coefficient. , is the nonlinear acceleration creep coefficient. To accelerate creep time factor.

[0042] like Figure 5 As shown, the improved Westprime constitutive model, after parameter identification and fitting evaluation, describes the process in segments. When the shear stress y is less than the contact interface yield strength, switch 2 is turned on, and the generalized Kelvin body and viscous element are activated. The model is used to describe the decay creep stage and the steady-state creep stage. When the shear stress y is greater than or equal to the contact interface yield strength, switch 1 is turned on, and the generalized Kelvin body, viscous element, and nonlinear creep component are activated. The model is used to describe the nonlinear creep stage.

[0043]

[0044] Table 1 shows the results of fitting equation (4) to the above normal stress (397.89 kPa) test. Figure 6The diagram shows the fitting results of the improved Westland constitutive model of the nonlinear creep component using Equation (4) based on the strain-time curve under a stress of 397.89 kPa with graded processing. The improved Westland constitutive model, after parameter identification and fitting evaluation using Equation (4), fits the creep stage of the contact interface of the upper hard and lower soft interbedded rock mass. The shear stress and the yield strength of the contact interface obtained through experiments are the main basis. When the shear stress is less than the yield strength of the contact interface, the model is used to describe the decay and steady-state creep stage; when the shear stress is greater than the yield strength of the contact interface, the model is used to describe the nonlinear accelerated creep stage. The improved Westland model fitting curve is calculated, and the average goodness of fit is R2≈0.9490. This fitting is performed by Origin software using the above Equation (4), indicating that the model can well describe the creep process of the contact interface of the upper hard and lower soft interbedded rock mass.

[0045] S5: The improved constitutive model of the West Prototype, after parameter identification and fitting evaluation, is applied to the deformation analysis and engineering prediction of the contact interface between hard and soft rocks.

[0046] It should be noted that this step is the final application stage of the modeling method. The core is to apply the improved constitutive model of the West Prototype, which has been fitted and verified, to actual geotechnical engineering, to provide technical support for long-term deformation analysis, creep trend prediction and engineering stability assessment of the contact interface between hard and soft rock layers, and to achieve the core purpose of patent application.

[0047] Compared with existing technologies, the improved Westland constitutive modeling method for hard-soft rock interfaces under ring shear creep tests provided by this invention has the following advantages: Based on the traditional Westland model, an improved Westland constitutive model is constructed by introducing a nonlinear creep component containing parameters such as the contact interface yield strength and the viscosity coefficient of nonlinear elements. This model has clear physical meaning and can effectively compensate for the shortcomings of traditional models in characterizing the accelerated creep stage. Simultaneously, parameter identification and fitting analysis are conducted using ring shear creep test data to achieve accurate matching between model parameters and the real mechanical response of the hard-soft rock interface, significantly improving the fitting accuracy of test data. This enhances the model's ability to describe the nonlinear characteristics of the entire process of contact interface decay creep, steady-state creep, and accelerated creep, especially accurately characterizing the nonlinear evolution process of accelerated creep. The key parameters in the model can be obtained through experiments and theoretical derivation, which can continuously and quantitatively describe the creep behavior of the interface between hard and soft rock layers at different stages. Ultimately, it provides reliable technical support for the long-term deformation prediction of the interface between hard and soft rock layers and the stability analysis of related geotechnical engineering, making up for the shortcomings of the existing West Prototype model in the characterization of ring shear creep at the interface between hard and soft rock layers, and helping to upgrade the technology in geotechnical engineering and geological disaster early warning, rock mechanics calculation technology.

[0048] This invention also provides an improved modeling system for the interface between hard and soft rock under ring shear creep tests, the system comprising: The test data acquisition module is used to conduct ring shear creep tests on the contact interface between hard and soft rock layers and obtain curve data of the entire shear-ring shear creep process. The data preprocessing and feature extraction module is used to preprocess the entire process curve data of the ring shear creep and extract the creep stage features; The constitutive model construction module is used to construct an improved constitutive model of Westpurus based on the traditional Westpurus model by introducing nonlinear creep components. The parameter identification and fitting evaluation module is used to identify and evaluate the parameters of the improved Westprobe constitutive model based on the preprocessed circumferential creep curve data. The engineering application module is used to apply the improved constitutive model of the West Prototype, after parameter identification and fitting evaluation, to the deformation analysis and engineering prediction of the contact interface between hard and soft rocks.

[0049] Compared with the prior art, the improved Xiyuan body modeling device for hard and soft rock interface under ring shear creep test provided by the embodiments of the present invention has the same beneficial effects as the improved Xiyuan body modeling method for hard and soft rock interface under ring shear creep test provided by the above technical solution, and will not be repeated here.

[0050] 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 scope of the technology 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. An improved method for modeling the Xiyuan body at the interface between hard and soft rock under ring shear creep test, characterized by... The sign is that, include: S1: Conduct ring shear creep tests on the contact interface between hard and soft rock layers to obtain the full-process curve data of ring shear creep. S2: Preprocess the entire process curve data of the ring shear creep and extract the creep stage features; S3: Based on the traditional Westprone model, an improved Westprone constitutive model is constructed by introducing a nonlinear creep component. S4: Based on the preprocessed circumferential creep curve data, parameter identification and fitting evaluation are performed on the improved Westprobe constitutive model; S5: The improved constitutive model of the West Prototype, after parameter identification and fitting evaluation, is applied to the deformation analysis and engineering prediction of the contact interface between hard and soft rocks.

2. The improved modeling method for the interface between hard and soft rock under ring shear creep test according to claim 1, characterized in that, Step S1 includes: The hard and soft rock were reshaped into a ring sample. The hard rock layer and the soft rock layer were combined to form the contact interface between the hard and soft rock layers. The ring sample was then subjected to a normal load and consolidated using a fully automatic servo dynamic control ring shearing device. A single-stage ring shear test was conducted by applying torque at a preset rate until the ring specimen failed shear, and the shear failure torque data was recorded. The shear failure torque data were applied in stages at 50%, 60%, 70%, 80%, 90%, and 95%, with each stress level applied for 6 hours, to obtain the full-process curve data of circumferential shear creep under different normal stresses.

3. The improved modeling method for the interface between hard and soft rock under ring shear creep test according to claim 2, characterized in that, The preprocessing described in step S2 includes: based on the Boltzmann superposition principle, decomposing the full-process circumferential shear creep curve data obtained under graded loading into single-stage creep curves under different shear stress levels.

4. The improved modeling method for the interface between hard and soft rock under ring shear creep test according to claim 1, characterized in that, Step S3 includes: Based on the traditional Westprime model composed of an ideal viscoplastic body and a generalized Kelvin body, a nonlinear creep component is introduced. The nonlinear creep component includes the contact interface yield strength, the viscosity coefficient of the nonlinear element, the nonlinear creep time, and the nonlinear creep parameter, thus obtaining an improved Westprime constitutive model with the nonlinear creep component.

5. The improved modeling method for the interface between hard and soft rock under ring shear creep test according to claim 4, characterized in that, In step S3, The traditional Westproton model formula is as follows: （1）； in, In response, For stress, For time, and These are the elastic moduli in Hookean and Kelvin bodies, respectively. and These are the viscosity coefficients in the generalized Kelvin and the ideal viscoplastic body, respectively. The contact interface yield strength; The constitutive equation for the nonlinear creep component is: （2）； in, The contact interface yield strength, The viscosity coefficient of a nonlinear element. To be related to nonlinear creep parameters The corresponding nonlinear creep time, These are nonlinear creep parameters; The improved constitutive model formula for the Westproton obtained after introducing the nonlinear creep component is as follows: （3）； in, In response, For stress, For time, and These are the elastic moduli in Hookean and Kelvin bodies, respectively. and These are the viscosity coefficients in the generalized Kelvin and the ideal viscoplastic body, respectively. The contact interface yield strength, The viscosity coefficient of a nonlinear element. To be related to nonlinear creep parameters The corresponding nonlinear creep time, This is a nonlinear creep parameter.

6. The improved modeling method for the interface between hard and soft rock under ring shear creep test according to claim 5, characterized in that, Step S4, which involves parameter identification and fitting analysis of the improved Westprobe constitutive model, includes: Nonlinear fitting software was used to identify parameters and evaluate the fit of the improved constitutive model of the West Primordial Body to obtain the goodness of fit. The improved constitutive model formula for the Westprobe, after parameter identification and fitting evaluation, is as follows: （4）； in, For shear strain, For the current time, To accelerate the creep characteristic time, , is the reciprocal of the instantaneous elastic shear modulus. , is the reciprocal of the delayed elastic shear modulus. , is the reciprocal of the first viscosity coefficient. , is the reciprocal of the steady-state viscosity coefficient. , is the nonlinear acceleration creep coefficient. To accelerate creep time factor.

7. The improved modeling method for the interface between hard and soft rock under ring shear creep test according to claim 1, characterized in that, Step S5 includes: The improved constitutive model of the West Plain, after parameter identification and fitting evaluation, is embedded into numerical analysis software to predict the creep deformation of the contact interface between hard and soft rock layers under long-term load. Based on the prediction results, it is determined whether the contact interface between hard and soft rock layers has entered the creep stage, so as to assess the long-term stability of geotechnical engineering and determine the timing of reinforcement treatment.

8. An improved modeling system for the interface between hard and soft rock under ring shear creep test, characterized by... The characteristics include: The test data acquisition module is used to conduct ring shear creep tests on the contact interface between hard and soft rock layers and obtain the full-process curve data of ring shear creep. The data preprocessing and feature extraction module is used to preprocess the entire process curve data of the ring shear creep and extract the creep stage features; The constitutive model construction module is used to construct an improved constitutive model of Westpurus based on the traditional Westpurus model by introducing nonlinear creep components. The parameter identification and fitting evaluation module is used to identify and evaluate the parameters of the improved Westprobe constitutive model by using the preprocessed circumferential creep full-process curve data. The engineering application module is used to apply the improved constitutive model of the West Prototype, after parameter identification and fitting evaluation, to the deformation analysis and engineering prediction of the contact interface between hard and soft rocks.

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