Fitting method and device for damping ratio development curve of cohesive soil

Abstract

The present application relates to the technical field of indoor soil unit dynamic characteristic testing, and in particular to a fitting method and device for a damping ratio development curve of clay soil, wherein the method comprises: preparing clay or gravel-mixed clay according to a preset moisture content to generate clay or gravel-mixed clay samples for indoor soil dynamic experiments; setting different levels of dynamic loading from small to large based on a target strain controlled loading mode to obtain hysteresis curves for each strain level and generate a schematic diagram of the development of damping ratio and dynamic shear strain; performing data fitting using a preset damping ratio fitting curve model suitable for clay soil under high shear strain to obtain a damping ratio fitting curve and the fitted R 2 Value; based on the fitted R 2 The final fitting model in the damping ratio fitting curve model is determined by the value. This solves the problem in related technologies that the development trend and characteristics of the damping ratio of clay and gravel-mixed clay under high shear strain cannot be accurately fitted and predicted.

Description

Technical Field

[0001] The present application relates to the technical field of indoor soil unit dynamic characteristics testing, and in particular to a fitting method and device for a damping ratio development curve of viscous soil. Background Art

[0002] Earthquakes are a major natural factor in triggering disasters. Studying the dynamic properties of soil—that is, evaluating its dynamic response and deformation behavior—can help scientifically assess the risk and severity of earthquake disasters, providing a scientific basis and technical support for earthquake disaster prediction, prevention, and mitigation. Furthermore, accurately assessing the dynamic properties of soil provides a crucial basis for dynamic response analysis in geotechnical engineering, guiding the design of geotechnical structures and the development of reinforcement plans, thereby improving their seismic resistance and safety.

[0003] In related technologies, the dynamic properties of soil are often described using two key parameters: the dynamic shear modulus and the damping ratio. These parameters are also essential for nonlinear site dynamic analysis of soils. Existing models primarily simulate the development of the damping ratio of clayey soils within the low to medium shear strain range (<1%). Within this range, the damping ratio typically exhibits a clear, continuous growth trend with increasing shear strain. However, the damping ratio of clayey soils develops differently under high shear strains (>1%). After reaching a peak value at high shear strains (>1%), the damping ratio enters a plateau, during which the damping ratio decreases slightly. Subsequently, the damping ratio begins to "rise again," often at a higher rate than the initial growth rate.

[0004] However, related technologies can only simulate the continuous growth trend of the soil damping ratio in the medium and low shear strain range. At the same time, the related models are unable to accurately capture and fit the "plateau" and "re-uplift" phenomena of the damping ratio of cohesive soil under high shear strain, resulting in an erroneous assessment of the development of the damping ratio of cohesive soil under high shear strain, affecting the accuracy of nonlinear dynamic analysis of soil sites under strong earthquakes, which urgently needs to be resolved. Summary of the Invention

[0005] The present application provides a fitting method and device for the damping ratio development curve of clay soil, so as to solve the problem in the related art that the damping ratio development trend and characteristics of clay and gravel-mixed clay under high shear strain cannot be accurately fitted and predicted.

[0006] The first aspect of the present application provides a fitting method for a damping ratio development curve of clay soil, comprising the following steps: preparing clay or gravel-mixed clay according to a preset moisture content to generate clay or gravel-mixed clay samples for indoor soil dynamic experiments; setting different levels of dynamic loading from small to large based on a target strain-controlled loading mode to obtain hysteresis curves for each strain level and generate a schematic diagram of the development of the damping ratio and dynamic shear strain; performing data fitting using a preset damping ratio fitting curve model suitable for clay soil under high shear strain to obtain a damping ratio fitting curve and a fitted R2 value; and determining a final fitting model in the damping ratio fitting curve model based on the fitted R2 value.

[0007] Optionally, in one embodiment of the present application, the expression of the damping ratio fitting curve model applicable to clayey soil under high shear strain may be, but is not limited to,:

[0008]

[0009]

[0010] Where D is the damping ratio, γ is the dynamic shear strain, and γ r is the reference shear strain, η, α, β and μ are the relevant fitting parameters of the control damping ratio development curve, which are related to the properties of the soil itself.

[0011] Optionally, in one embodiment of the present application, when different levels of dynamic loading are set from small to large, the set maximum dynamic shear strain level reaches 1% or above.

[0012] Optionally, in one embodiment of the present application, the calculation formula of the damping ratio may be, but is not limited to,:

[0013]

[0014] Where D is the damping ratio, A H is the area of ​​the hysteresis curve, A Δ It is the area of ​​the right triangle enclosed by the horizontal and vertical coordinate values ​​of the hysteresis loop vertex.

[0015] Optionally, in one embodiment of the present application, determining the final fitting model in the damping ratio fitting curve model based on the R2 value after fitting includes: comparing the R2 value of at least one fitting model in the damping ratio fitting curve model; and taking the fitting model with the highest R2 value as the final fitting model.

[0016] A second aspect of the present application provides a fitting device for a damping ratio development curve of clay soil, comprising: a first generation module for preparing clay or gravel-mixed clay according to a preset moisture content to generate clay or gravel-mixed clay samples for indoor soil dynamic experiments; a second generation module for setting different levels of dynamic loading from small to large based on a loading mode controlled by a target strain to obtain hysteresis curves for each strain level and generate a development diagram of the damping ratio and dynamic shear strain; a fitting module for performing data fitting using a preset damping ratio fitting curve model suitable for clay soil under high shear strain to obtain a damping ratio fitting curve and an R2 value after fitting; and a determination module for determining a final fitting model in the damping ratio fitting curve model based on the R2 value after fitting.

[0017] Optionally, in one embodiment of the present application, the expression of the damping ratio fitting curve model applicable to clayey soil under high shear strain may be, but is not limited to,:

[0018]

[0019]

[0020] Where D is the damping ratio, γ is the dynamic shear strain, and γ r is the reference shear strain, η, α, β and μ are the relevant fitting parameters of the control damping ratio development curve, which are related to the properties of the soil itself.

[0021] Optionally, in one embodiment of the present application, the second generating module is further configured to set the maximum dynamic shear strain level to 1% or above when setting different levels of dynamic loading from small to large.

[0022] Optionally, in one embodiment of the present application, the calculation formula of the damping ratio may be, but is not limited to,:

[0023]

[0024] Where D is the damping ratio, A H is the area of ​​the hysteresis curve, A Δ It is the area of ​​the right triangle enclosed by the horizontal and vertical coordinate values ​​of the hysteresis loop vertex.

[0025] Optionally, in one embodiment of the present application, the determining module includes: a comparing unit for comparing the R of at least one fitting model in the damping ratio fitting curve model. 2 value; determining unit for converting the R 2 The fitting model with the highest value is taken as the final fitting model.

[0026] A third aspect of the present application provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the fitting method for the damping ratio development curve of clay soil as described in the above embodiment.

[0027] A fourth aspect of the present application provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the above-mentioned fitting method for the damping ratio development curve of clay soil.

[0028] The fifth aspect of the present application provides a computer program product, including a computer program, which is executed to implement the above-mentioned fitting method for the damping ratio development curve of clay soil.

[0029] In the embodiment of the present application, an indoor soil dynamic test is conducted on clay or gravel-mixed clay, and based on the loading mode of target strain control, hysteresis curves of various strain levels are obtained, and a schematic diagram of the development of damping ratio and dynamic shear strain is generated. Then, a preset damping ratio fitting curve model suitable for clay under high shear strain is used to fit the data to obtain the damping ratio fitting curve and the R after fitting. 2 value, and finally based on the R after fitting 2 The final fitting model in the damping ratio fitting curve model is determined by using the value of the damping ratio fitting curve, thus filling the gap in the conventional indoor soil dynamic test method for fitting and predicting the damping ratio development curve of clay under high shear strain. It accurately captures the characteristics of the damping ratio re-uplift of clay under high shear strain. The fitting effect is good, the model has few parameters, and it is easy to operate. It can provide a reference for the dynamic response of soil sites under strong earthquakes and the seismic design of soils. This solves the problem of the inability to accurately fit and predict the damping ratio development trend and characteristics of clay and gravel-mixed clay under high shear strain in related technologies.

[0030] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0032] Figure 1 A flowchart of a method for fitting a damping ratio development curve of clay soil provided in accordance with an embodiment of the present application;

[0033] Figure 2 A schematic diagram of a logic architecture for fitting a damping ratio development curve of cohesive soil provided in one embodiment of the present application;

[0034] Figure 3 A schematic diagram comparing the measured damping ratio of gravel-mixed clay with different stone contents and the fitting curve of the proposed model provided in one embodiment of the present application;

[0035] Figure 4 A schematic diagram comparing the measured damping ratio of gravel-mixed clay under different effective confining pressures with the fitting curve of the proposed model provided in one embodiment of the present application;

[0036] Figure 5 A schematic diagram comparing the measured value of the sensitive clay damping ratio and the fitting curve of the proposed model provided in one embodiment of the present application;

[0037] Figure 6 Schematic diagram of a block diagram of a device for fitting a damping ratio development curve of cohesive soil according to an embodiment of the present application;

[0038] Figure 7 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application.

[0039] Reference numerals:

[0040] Among them, 10 is a fitting device for the damping ratio development curve of clay soil; 100 is a first generation module, 200 is a second generation module, 300 is a fitting module, 400 is a determination module; 701 is a memory, 702 is a processor, and 703 is a communication interface. DETAILED DESCRIPTION

[0041] The following describes in detail embodiments of the present application, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0042] The following describes the fitting method and device for the damping ratio development curve of clay soil according to the embodiment of the present application with reference to the accompanying drawings. In view of the problem that the related technologies mentioned in the above background technology cannot accurately fit and predict the damping ratio development trend and characteristics of clay and gravel-mixed clay under high shear strain, the present application provides a fitting method for the damping ratio development curve of clay soil. In this method, indoor soil dynamic experiments can be carried out on clay or gravel-mixed clay, and based on the loading mode controlled by the target strain, hysteresis curves of each strain level are obtained, and a schematic diagram of the development of damping ratio and dynamic shear strain is generated at the same time. Then, a preset damping ratio fitting curve model suitable for clay soil under high shear strain is used to perform data fitting to obtain the damping ratio fitting curve and the fitted R 2 value, and finally based on the R after fitting 2The final fitting model in the damping ratio fitting curve model is determined by using the value of the damping ratio fitting curve, thus filling the gap in the conventional indoor soil dynamic test method for fitting and predicting the damping ratio development curve of clay under high shear strain. It accurately captures the characteristics of the damping ratio re-uplift of clay under high shear strain. The fitting effect is good, the model has few parameters, and it is easy to operate. It can provide a reference for the dynamic response of soil sites under strong earthquakes and the seismic design of soils. This solves the problem of the inability to accurately fit and predict the damping ratio development trend and characteristics of clay and gravel-mixed clay under high shear strain in related technologies.

[0043] Specifically, Figure 1 A flow chart of a method for fitting the damping ratio development curve of clay soil provided in an embodiment of the present application.

[0044] like Figure 1 As shown in Figure 2, the fitting method for the damping ratio development curve of cohesive soil includes the following steps:

[0045] In step S101, clay or gravel-mixed clay is prepared according to a preset moisture content to generate a clay or gravel-mixed clay sample for indoor soil dynamics testing.

[0046] It is understandable that the embodiments of the present application can select clay or gravel-mixed clay as raw materials, make the clay or gravel-mixed clay into soil according to a specific moisture content, and prepare samples of the clay or gravel-mixed clay according to geotechnical test method standards to conduct indoor soil dynamics experiments.

[0047] It should be noted that the damping ratio in the embodiments of the present application can be obtained, but is not limited to, by calculating the hysteresis curve of the soil, i.e., the dynamic stress-strain curve, obtained through indoor soil dynamics testing. Indoor soil dynamics testing requires experimental equipment capable of testing at high strain levels. Depending on the equipment used, the tests can be categorized as dynamic triaxial tests, dynamic simple shear tests, and dynamic direct shear tests.

[0048] In some embodiments, limestone, a common material in geotechnical engineering, can be selected as the gravel raw material, and a mixture of kaolin and yellow clay can be selected as the matrix clay. A fixed amount of water is added to the matrix clay according to an optimal moisture content of ω = 18% and thoroughly stirred. The moistened gravel is then added to the clay, mixed and stirred again, and the prepared gravel-mixed clay is sealed for more than 24 hours. In the present embodiment, gravel-mixed clays with stone contents of 15%, 35%, and 55% are prepared. The prepared gravel-mixed clays are sampled and saturated according to geotechnical test method standards. The gravel-mixed clays are then compacted into cylindrical samples with a diameter of 100 mm and a height of 200 mm. The samples are vacuumed for 2 hours before the experiment, then water is injected and allowed to stand for 24 hours to fully saturate the samples. Finally, the saturated gravel-mixed clay samples are subjected to undrained consolidation dynamic triaxial tests with stepwise loading according to geotechnical test method standards.

[0049] Therefore, the embodiment of the present application ensures the realization of the subsequent hysteresis curve and the development diagram of the damping ratio and dynamic shear strain by conducting indoor soil dynamic experiments on clay.

[0050] In step S102 , based on the loading mode of target strain control, different levels of dynamic loading are set from small to large to obtain hysteresis curves of various strain levels and generate a development diagram of damping ratio and dynamic shear strain.

[0051] It is understandable that the embodiment of the present application can select a strain-controlled loading mode, setting different levels of dynamic loading from small to large, and after conducting indoor soil dynamic experiments, such as Figure 2 As shown in the figure, by calculating the experimental data, that is, calculating the hysteresis curves of each strain level, the damping ratio D can be obtained, and a schematic diagram of the development of the damping ratio D and the dynamic shear strain γ can be made.

[0052] Those skilled in the art will appreciate that strain-controlled loading is the preferred loading method for dynamic experimental equipment, facilitating loading to a specific strain level. Stress-controlled loading can also be used to achieve a specific strain level. A method for plotting the development of the damping ratio D versus the dynamic shear strain γ is to logarithmize the dynamic shear strain γ and then plot it in conjunction with the damping ratio D.

[0053] In some embodiments, when performing a step-by-step loading dynamic triaxial test of undrained consolidation on a saturated gravel-mixed clay sample according to the geotechnical test method standard, the present application may, but is not limited to, adopt a strain loading mode, the shear strain range of the test may be 0.075%-7.5%, the frequency f may be 1 Hz, the number of vibrations per level of excitation may be 5 times, and the initial consolidation pressure p' may be set to 400 kPa.

[0054] According to the dynamic triaxial test, the embodiment of the present application can obtain the hysteresis curve of gravel-mixed clay, and the third hysteresis loop of each level of excitation is selected to calculate the damping ratio. The formula can be, but is not limited to:

[0055]

[0056] Where D is the damping ratio, A H is the area of ​​the hysteresis curve, A Δ It is the area of ​​the right triangle enclosed by the horizontal and vertical coordinate values ​​of the hysteresis loop vertex.

[0057] In the present embodiment, the dynamic shear modulus G and damping ratio D of gravel-mixed clay can be calculated using the above formula. The damping ratio D is plotted against the logarithmic shear strain logγ to obtain a schematic diagram of the damping ratio development. Since the dynamic triaxial test measures axial strain, the present embodiment requires converting axial strain into shear strain. The formula for this conversion can be, but is not limited to, the following:

[0058] γ=(1+μ)ε a

[0059] Where γ is the shear strain, μ is the Poisson's ratio, and ε is the a is the axial strain, and the Poisson's ratio μ is empirically taken as 0.5. In the embodiment of the present application, the ratio of the dynamic shear modulus to the small strain shear modulus G / G0 can be plotted together with the logarithmic shear strain logγ to obtain a dynamic shear modulus ratio attenuation graph G / G0~logγ, and the shear strain when G / G0=0.5 is taken as the reference shear strain γ r value.

[0060] Therefore, the embodiment of the present application selects a strain-controlled loading mode to obtain hysteresis curves at various strain levels and generates a schematic diagram of the development of the damping ratio and dynamic shear strain, thereby providing a theoretical basis for subsequently obtaining the damping ratio fitting curve of the clay or gravel-mixed clay and the R2 value after fitting.

[0061] Optionally, in one embodiment of the present application, when different levels of dynamic loading are set from small to large, the set maximum dynamic shear strain level reaches 1% or above.

[0062] It should be noted that in the embodiment of the present application, different levels of dynamic loading are set from small to large, and the maximum dynamic shear strain level set should reach 1% or above.

[0063] In actual implementation, the specific strain values ​​at which the damping ratio rises under high shear strain will vary for different clayey soils, depending on the soil's properties and the choice of dynamic test equipment. Relevant data indicate that the damping ratio typically rises within a shear strain range of 2% to 5%. Therefore, this application recommends that the maximum loading level for the experiment be 5% or higher. This setting can be customized by professionals in this field based on actual conditions.

[0064] Therefore, the embodiment of the present application can provide theoretical support for achieving the damping ratio re-raising phenomenon by setting the maximum dynamic shear strain level to 1% or above.

[0065] Optionally, in one embodiment of the present application, the calculation formula of the damping ratio may be, but is not limited to,:

[0066]

[0067] Where D is the damping ratio, A H is the area of ​​the hysteresis curve, A Δ It is the area of ​​the right triangle enclosed by the horizontal and vertical coordinate values ​​of the hysteresis loop vertex.

[0068] It should be noted that the embodiment of the present application includes the hysteresis curve area A H The area A of the right triangle formed by the horizontal and vertical coordinate values ​​of the hysteresis loop vertex Δ , and calculate the final damping ratio D by the following formula:

[0069]

[0070] Therefore, the embodiment of the present application can be realized by calculating the hysteresis curve area A H The area A of the right triangle formed by the horizontal and vertical coordinate values ​​of the hysteresis loop vertex Δ The calculation formula of the damping ratio D is obtained, which is used for the subsequent calculation of the damping ratio fitting curve and the R after fitting. 2 The value provides a theoretical basis.

[0071] In step S103, a damping ratio fitting curve model suitable for clayey soil under high shear strain is used to perform data fitting to obtain a damping ratio fitting curve and the R 2 value.

[0072] It is understandable that the embodiment of the present application can use the preset damping ratio fitting curve model suitable for clay under high shear strain to fit the experimental data to obtain the damping ratio fitting curve of the clay or gravel-mixed clay and the R 2 value.

[0073] In some embodiments, according to the dynamic triaxial test, the embodiment of the present application can fit the experimental data of the damping ratio of the gravel-mixed clay tested according to formulas (1) and (2), respectively, to obtain the damping ratio fitting curve of the gravel-mixed clay with different stone contents under high shear strain and the fitted R 2 For example, when using gravel clay with stone content of 15%, 35%, and 55% to fit using formula (1), the fitted R 2 The values ​​are 0.9436, 0.8464, and 0.8460 respectively. When fitting using formula (2), the R 2 The values ​​are not converged, 0.9872, and not converged, respectively. Therefore, the experimental data with stone content of 15% and 55% can choose formula (1) as the final fitting formula, while the experimental data with stone content of 35% can choose formula (2) as the final fitting formula.

[0074] In the above examples, the measured values ​​of the damping ratio of gravel-mixed clay with different stone contents under high shear strain are well fitted with the proposed method. The proposed method fits the whole process fitting curve of the damping ratio of gravel-mixed clay with different stone contents from medium and low strain to high strain, and accurately captures the "plateau" and "re-rise" phenomena of the damping ratio of gravel-mixed clay under high shear strain. The fitting results are good, as shown in the following figure. Figure 3shown.

[0075] An embodiment of the present application verifies that the proposed damping ratio curve fitting method can well fit the development trend and characteristics of the damping ratio of gravel-mixed clay with different stone contents under high shear strain in dynamic triaxial tests, with reliable results and simple operation.

[0076] In other embodiments, according to the dynamic triaxial test, the embodiment of the present application can fit the experimental data of the damping ratio of the gravel-mixed clay tested according to formula (1) and formula (2), respectively, to obtain the damping ratio fitting curve of the gravel-mixed clay under high shear strain under different effective confining pressures and the fitted R 2 For example, the effective confining pressure is 400kPa, 900kPa and 1400kPa, and the R fitted by formula (1) is 2 The values ​​are 0.8460, 0.9940, and 0.9382, respectively. The R 2 The values ​​are not converged, 0.9648, and 0.8601, respectively. Therefore, formula (1) is selected as the final fitting formula.

[0077] The above examples show that the measured damping ratio of gravel-mixed clay under high shear strain under different effective confining pressures is well consistent with the proposed method. Figure 3 The proposed method is shown in the figure. The fitting curve of the whole process of the damping ratio of gravel-mixed clay from medium and low strain to high strain under different effective confining pressures is obtained. The phenomenon of "plateau" and "re-uplift" of the damping ratio of gravel-mixed clay under high shear strain is captured more accurately. The fitting results are good. Figure 4 The examples of this application verify that the proposed damping ratio curve fitting method can well fit the development trend and characteristics of the damping ratio of gravel-mixed clay under high shear strain under different effective confining pressures in dynamic triaxial tests, and the results are reliable and easy to operate.

[0078] Furthermore, in some embodiments, the present application can also use sensitive clay to conduct dynamic single shear tests under special triaxial conditions with different loading frequencies. The shear strain range of the test can be 0.004%-3%, the effective confining pressure p' can be 60kPa, and the loading frequency f can be 1Hz. According to formula (1) and formula (2), the damping ratio experimental data of the sensitive clay are fitted respectively, and the damping ratio fitting curve of the sensitive clay under high shear strain at different loading frequencies and the fitted R can be obtained. 2 The experimental data with loading frequency of f = 1 Hz are fitted with R using formula (1). 2 The value is 0.9377, and the R fitted by formula (2) 2 The value is not converged, so formula (1) is selected as the final fitting formula.

[0079] The above examples show that under different loading frequencies, the measured values ​​of the damping ratio of sensitive clay under high shear strain are well fitted with the proposed method. The proposed method fits the whole process fitting curve of the damping ratio of sensitive clay from medium and low strain to high strain under different loading frequencies, and accurately captures the "plateau" and "re-lift" phenomena of the damping ratio of sensitive clay under high shear strain. The fitting results are good, as shown in the following figure. Figure 5 The examples of this application verify that the proposed damping ratio curve fitting method can well fit the development trend and characteristics of the damping ratio of gravel-mixed clay under high shear strain at different loading frequencies in dynamic single shear tests, with reliable results and simple operation.

[0080] Optionally, in one embodiment of the present application, the expression of the damping ratio fitting curve model applicable to clayey soil under high shear strain may be, but is not limited to,:

[0081]

[0082]

[0083] Where D is the damping ratio, γ is the dynamic shear strain, and γ r is the reference shear strain, η, α, β and μ are the relevant fitting parameters of the control damping ratio development curve, which are related to the properties of the soil itself.

[0084] It should be noted that the embodiment of the present application includes dynamic shear strain γ, reference shear strain γ r and fitting parameters and other variables, and calculate the final damping ratio by the following formula, which can be but is not limited to:

[0085]

[0086]

[0087] Where D is the damping ratio; γ is the dynamic shear strain; γ r is the reference shear strain, the reference shear strain γ r is the maximum shear stress τ of this group of samples max The ratio of the shear modulus to the small strain shear modulus G0 can also be determined by reference to the empirical method. For clay soil, the shear strain value when the ratio of the shear modulus to the small strain shear modulus G / G0 = 0.5 is usually taken; η, α, β and μ are the relevant fitting parameters for controlling the damping ratio development curve, which are related to the properties of the soil itself.

[0088] Therefore, the embodiment of the present application is to calculate the dynamic shear strain γ and the reference shear strain γ. r By calculating the variables such as the damping ratio D and the fitting parameters, the calculation formula of the damping ratio D is obtained, which provides a theoretical basis for the subsequent development diagram of the damping ratio D and the dynamic shear strain γ.

[0089] In step S104, based on the fitted R 2 The value determines the final fitting model in the damping ratio fitting curve model.

[0090] It is understandable that the embodiments of the present application can be based on R 2 The damping ratio fitting curve model of clay under high shear strain is selected for fitting. In addition, the embodiment of the present application can also be selected according to the shape of the fitting curve. The main criterion is whether the shape of the fitting curve conforms to the trend of the damping ratio rising again under high shear strain. Generally speaking, R 2 The higher the value, the better the shape of the fitted curve.

[0091] Therefore, the embodiments of the present application can accurately capture and simulate the phenomenon of "re-uplift" of clay under high shear strain, thereby filling the gap in the current engineering field in the lack of a fitting model for the damping ratio of clay under high shear strain.

[0092] Optionally, in one embodiment of the present application, based on the fitted R 2 The method comprises the following steps: determining a final fitting model in the damping ratio fitting curve model by using a value, comprising: comparing R of at least one fitting model in the damping ratio fitting curve model; 2 value; R 2 The fitting model with the highest value is taken as the final fitting model.

[0093] It is understandable that the embodiment of the present application needs to be based on the R 2 The embodiment of the present application can first compare the R of at least one fitting model in the damping ratio fitting curve model. 2 value, and then find the highest R 2 value, and finally R 2 The fitting model with the highest value is taken as the final fitting model.

[0094] As an achievable method, the embodiment of the present application can use formula (1) and formula (2) to fit the experimental data to obtain the damping ratio fitting curve of the clay or gravel-mixed clay, and obtain the damping ratio fitting curve and the fitted R 2 According to the fitting results, if the R value of formula (1) is higher than that of formula (2), 2 If the value is higher, then choose formula (1) as the final fitting model; if formula (2) is higher than formula (1) 2 If the value is higher, formula (2) is selected as the final fitting model.

[0095] Therefore, the embodiment of the present application accurately fits the entire process of the development of the damping ratio of clay from low strain to high strain under various conditions, and the fitting model can provide data for equivalent linear dynamic analysis and provide a reference for seismic design of geotechnical engineering.

[0096] According to the fitting method for the damping ratio development curve of clay soil proposed in the embodiment of the present application, in this method, indoor soil dynamic experiments are carried out on clay or gravel-mixed clay, and based on the loading mode controlled by the target strain, hysteresis curves of each strain level are obtained, and a schematic diagram of the development of the damping ratio and dynamic shear strain is generated at the same time. Then, a preset damping ratio fitting curve model suitable for clay soil under high shear strain is used to perform data fitting to obtain the damping ratio fitting curve and the fitted R 2 value, and finally based on the R after fitting 2 The final fitting model in the damping ratio fitting curve model is determined by using the value of the damping ratio fitting curve, thus filling the gap in the conventional indoor soil dynamic test method for fitting and predicting the damping ratio development curve of clay under high shear strain. It accurately captures the characteristics of the damping ratio re-uplift of clay under high shear strain. The fitting effect is good, the model has few parameters, and it is easy to operate. It can provide a reference for the dynamic response of soil sites under strong earthquakes and the seismic design of soils. This solves the problem of the inability to accurately fit and predict the damping ratio development trend and characteristics of clay and gravel-mixed clay under high shear strain in related technologies.

[0097] Next, a fitting device for a damping ratio development curve of clay soil proposed in an embodiment of the present application will be described with reference to the accompanying drawings.

[0098] Figure 6 Schematic diagram of a block diagram of a fitting device for a damping ratio development curve of cohesive soil according to an embodiment of the present application.

[0099] like Figure 6 As shown, the fitting device 10 for the damping ratio development curve of clay soil includes: a first generating module 100 , a second generating module 200 , a fitting module 300 and a determining module 400 .

[0100] The first generation module 100 is used to make soil from clay or gravel-mixed clay according to a preset moisture content to generate clay or gravel-mixed clay samples for indoor soil dynamics experiments.

[0101] The second generation module 200 is used to set different levels of dynamic loading from small to large based on the loading mode of target strain control to obtain hysteresis curves of various strain levels and generate a schematic diagram of the development of damping ratio and dynamic shear strain.

[0102] The fitting module 300 is used to perform data fitting using a preset damping ratio fitting curve model suitable for clay soil under high shear strain to obtain a damping ratio fitting curve and the R2 value.

[0103] Determine module 400, for determining the R 2 The value determines the final fitting model in the damping ratio fitting curve model.

[0104] Optionally, in one embodiment of the present application, the fitting device 10 for the damping ratio development curve of clay soil further includes an expression of a damping ratio fitting curve model for clay soil under high shear strain, which may be, but is not limited to:

[0105]

[0106]

[0107] Where D is the damping ratio, γ is the dynamic shear strain, and γ r is the reference shear strain, η, α, β and μ are the relevant fitting parameters of the control damping ratio development curve, which are related to the properties of the soil itself.

[0108] Optionally, in one embodiment of the present application, the second generation module 200 is further configured to set the maximum dynamic shear strain level to 1% or above when setting different levels of dynamic loading from small to large.

[0109] Optionally, in one embodiment of the present application, the fitting device 10 for the damping ratio development curve of clay soil further includes: a calculation formula for the damping ratio may be, but is not limited to,:

[0110]

[0111] Where D is the damping ratio, A H is the area of ​​the hysteresis curve, A Δ It is the area of ​​the right triangle enclosed by the horizontal and vertical coordinate values ​​of the hysteresis loop vertex.

[0112] Optionally, in one embodiment of the present application, the determination module 400 includes: a comparison unit and a generation unit.

[0113] The comparison unit is used to compare the R of at least one fitting model in the damping ratio fitting curve model. 2 value.

[0114] Determine the unit for R 2 The fitting model with the highest value is taken as the final fitting model.

[0115] It should be noted that the above explanation of the embodiment of the fitting method for the damping ratio development curve of cohesive soil is also applicable to the fitting device for the damping ratio development curve of cohesive soil in this embodiment, and will not be repeated here.

[0116] According to the fitting device for the damping ratio development curve of clay soil proposed in the embodiment of the present application, clay or gravel-mixed clay samples are first generated by the acquisition module to conduct indoor soil dynamic experiments; secondly, different levels of dynamic loading are set from small to large by the generation module to obtain hysteresis curves of each strain level and generate a schematic diagram of the development of damping ratio and dynamic shear strain; thirdly, the fitting module uses a preset damping ratio fitting curve model suitable for clay soil under high shear strain to perform data fitting to obtain the damping ratio fitting curve and the fitted R 2 Finally, the module is determined based on the R 2 The final fitting model in the damping ratio fitting curve model is determined by using the value of the damping ratio fitting curve, thus filling the gap in the conventional indoor soil dynamic test method for fitting and predicting the damping ratio development curve of clay under high shear strain. It accurately captures the characteristics of the damping ratio re-uplift of clay under high shear strain. The fitting effect is good, the model has few parameters, and it is easy to operate. It can provide a reference for the dynamic response of soil sites under strong earthquakes and the seismic design of soils. This solves the problem of the inability to accurately fit and predict the damping ratio development trend and characteristics of clay and gravel-mixed clay under high shear strain in related technologies.

[0117] Figure 7 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. The electronic device may include:

[0118] Memory 701 , processor 702 , and computer programs stored in the memory 701 and executable on the processor 702 .

[0119] When the processor 702 executes the program, the fitting method for the damping ratio development curve of clay provided in the above embodiment is implemented.

[0120] Furthermore, the electronic device further includes:

[0121] The communication interface 703 is used for communication between the memory 701 and the processor 702 .

[0122] The memory 701 is used to store computer programs that can be run on the processor 702 .

[0123] The memory 701 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0124] If the memory 701, processor 702, and communication interface 703 are implemented independently, the communication interface 703, memory 701, and processor 702 can be interconnected via a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus. Buses can be divided into address buses, data buses, control buses, etc. For ease of representation, Figure 7 Only one thick line is used in the diagram, but this does not mean that there is only one bus or one type of bus.

[0125] Optionally, in a specific implementation, if the memory 701, the processor 702 and the communication interface 703 are integrated on a chip, the memory 701, the processor 702 and the communication interface 703 can communicate with each other through an internal interface.

[0126] The processor 702 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0127] An embodiment of the present application further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-mentioned fitting method for the damping ratio development curve of clay soil.

[0128] The present application also provides a computer program product, including a computer program, which, when executed, is used to implement the above-mentioned fitting method for the damping ratio development curve of clay soil.

[0129] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or N embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0130] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Thus, a feature specified as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of this application, "N" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0131] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or N executable instructions for implementing a custom logical function or process step, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may be performed in a different order than shown or discussed, including performing functions in a substantially simultaneous manner or in a reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present application pertain.

[0132] The logic and / or steps represented in the flowcharts or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing the logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (e.g., a computer-based system, a system including a processor, or other system that can fetch and execute instructions from an instruction execution system, apparatus, or device). For purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include the following: an electrical connection with one or N wires (electronic devices), a portable computer disk cartridge (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and programmable read-only memory (EPROM or flash memory), fiber optic devices, and a portable compact disc read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program can be obtained electronically by optically scanning the paper or other medium and then editing, interpreting or processing it in other suitable ways as necessary, and then storing it in a computer memory.

[0133] It should be understood that various parts of the present application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiment, the N steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. If implemented using hardware, as in another embodiment, it can be implemented using any one or a combination of the following technologies known in the art: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application-specific integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0134] Those skilled in the art will understand that all or part of the steps in the method of the above embodiment can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiment.

[0135] In addition, the functional units in the various embodiments of the present application may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into a module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0136] The storage medium mentioned above may be a read-only memory, a magnetic disk, or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present application. Persons skilled in the art may make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

Claims

1. A fitting method for the damping ratio development curve of clay soil, characterized in that: The following steps are involved: Prepare clay or gravel-mixed clay samples according to a preset moisture content for indoor soil dynamics testing; Based on the target strain controlled loading mode, different levels of dynamic loading are set from small to large to obtain hysteresis curves at each strain level and generate a schematic diagram of the development of damping ratio and dynamic shear strain; The data is fitted using the preset damping ratio fitting curve model suitable for clay soil under high shear strain to obtain the damping ratio fitting curve and the R after fitting. 2 value; Based on the R 2 The value determines the final fitting model in the damping ratio fitting curve model; The damping ratio fitting curve model applicable to clay soil under high shear strain is expressed as follows: ， ， in, D is the damping ratio, γ is the dynamic shear strain, γ r is the reference shear strain, η 、 α 、 β and μ To control the relevant fitting parameters of the damping ratio development curve, which is related to the properties of the soil itself; Wherein, the R based on the fitting 2 The method comprises the following steps: determining the final fitting model in the damping ratio fitting curve model by comparing the R values ​​of the models in the damping ratio fitting curve model; 2 value; the R 2 The model with the highest value is taken as the final fitted model.

2. The method according to claim 1, characterized in that in, When setting different levels of dynamic loading from small to large, the maximum dynamic shear strain level is set to 1% and above.

3. The method according to claim 1, characterized in that The calculation formula of the damping ratio is: ， in, D is the damping ratio, A H is the area of ​​the hysteresis curve, A Δ It is the area of ​​the right triangle enclosed by the horizontal and vertical coordinate values ​​of the hysteresis loop vertex.

4. A fitting device for the damping ratio development curve of clay soil, characterized in that: include: The first generation module is used to make soil from clay or gravel-mixed clay according to a preset moisture content to generate clay or gravel-mixed clay samples for indoor soil dynamics experiments; The second generation module is used to set different levels of dynamic loading from small to large based on the loading mode of target strain control to obtain hysteresis curves at each strain level and generate a schematic diagram of the development of damping ratio and dynamic shear strain; The fitting module is used to fit the data using the preset damping ratio fitting curve model suitable for clay soil under high shear strain to obtain the damping ratio fitting curve and the R after fitting. 2 value; Determine the module for R based on the fitting 2 The value determines the final fitting model in the damping ratio fitting curve model; The damping ratio fitting curve model applicable to clay soil under high shear strain is expressed as follows: ， ， in, D is the damping ratio, γ is the dynamic shear strain, γ r is the reference shear strain, η 、 α 、 β and μ To control the relevant fitting parameters of the damping ratio development curve, which is related to the properties of the soil itself; The determination module includes: a comparison unit for comparing the R of each model in the damping ratio fitting curve model; 2 value; determining unit for converting the R 2 The model with the highest value is taken as the final fitted model.

5. An electronic device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the fitting method for the damping ratio development curve of clay soil according to any one of claims 1 to 3.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that: The program is executed by a processor to implement the fitting method for the damping ratio development curve of clay soil as claimed in any one of claims 1 to 3.

7. A computer program product comprising a computer program, characterized in that The computer program is executed to implement the fitting method for the damping ratio development curve of clay soil according to any one of claims 1 to 3.

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