Method and System for Determining Ground Motion Intensity Characterization Parameters Based on LASSO Method

Abstract

The present application provides a method and system for determining a ground motion intensity characterization parameter based on the LASSO method. The method includes the following steps: using ground motion parameters as the independent variable of the regularization method; using the elastoplastic time history analysis results of ground motion records as the dependent variable of the regularization method; and determining the ground motion intensity characterization parameters of each structural response based on the LASSO method according to the obtained dependent variable and independent variable. By using the LASSO method to select the dependent variable and independent variable and screening the ground motion parameters, the present application realizes the determination of the corresponding characterization parameters of the ground motion intensity for different structural responses.

Description

Technical Field

[0001] This application relates to the technical field of earthquake resistance in civil engineering, and specifically relates to a method and system for determining ground motion intensity characterization parameters based on the LASSO method. Background Art

[0002] The parameters contained in ground motion records are multivariate. For example, the maximum ground acceleration, the maximum ground velocity, the maximum spectral acceleration, etc. When analyzing the seismic performance of structures, it is often necessary to select the most representative ground motion parameter to reflect the intensity of the ground motion. For different structural responses, the corresponding ground motion intensity characterization parameters may be different.

[0003] There is a lack of a method in the prior art that can determine the intensity characterization parameters for different structural responses. Summary of the Invention

[0004] This application provides a method for determining ground motion intensity characterization parameters based on the LASSO method, which can solve the technical problem in the prior art of how to determine the ground motion intensity characterization parameters for different structural responses.

[0005] In a first aspect, this application provides a method for determining ground motion intensity characterization parameters based on the LASSO method, including the following steps:

[0006] Use ground motion parameters as the independent variable of the regularization method;

[0007] Use the elastoplastic time history analysis results of ground motion records as the dependent variable of the regularization method;

[0008] Based on the obtained dependent variable and independent variable, determine the ground motion intensity characterization parameters for each structural response based on the LASSO method.

[0009] Combined with the first aspect, in one implementation, the step of using ground motion parameters as the independent variable of the regularization method specifically includes the following steps:

[0010] Obtain ground motion records;

[0011] Extract ground motion parameters from the obtained ground motion records.

[0012] Combined with the first aspect, in one implementation, the step of using the elastoplastic time history analysis results of ground motion records as the dependent variable of the regularization method specifically includes the following steps:

[0013] Obtain ground motion records;

[0014] Build a finite element model of the structure;

[0015] Based on the obtained ground motion records and finite element models, the elastic-plastic time history analysis structural response results of the ground motion records are obtained, and the obtained elastic time history analysis structural response results are used as the dependent variables of the regularization method.

[0016] Combined with the first aspect, in an implementation manner, the step of determining the ground motion intensity characterization parameters of each structural response based on the LASSO method according to the obtained dependent variables and independent variables specifically includes the following steps:

[0017] According to the obtained dependent variables and independent variables, taking the sum of the absolute values of the regression coefficients as the penalty function to compress the regression coefficients, and reducing the coefficients of other features to zero, the LASSO regularization method is used to screen and obtain the ground motion intensity characterization parameters of each structural response.

[0018] Combined with the first aspect, in an implementation manner, the algorithm formula of the LASSO regularization method is:

[0019]

[0020] In the formula, β is the regression coefficient vector β = [β1, β2,..., β n T , the β value is used to estimate the importance of ground motion parameters; C is the base shear force or the maximum inter-story drift, x is the vector of ground motion parameters, x = [x1, x2,..., x n T ; W T β is the penalty function; W T is a vector with values of ±1 for each item, and the sign of each item is the same as the sign of the corresponding item in the β vector; λ is the regularization coefficient, which is used to control the degree of compression of the regression coefficients.

[0021] Combined with the first aspect, in an implementation manner, when the β value is positive, the ground motion parameter is positively correlated with the structural response; when the β value is negative, the ground motion parameter is negatively correlated with the structural response.

[0022] Combined with the first aspect, in an implementation manner, the larger the absolute value of the β value, the greater the influence of the ground motion parameter on the structural response.

[0023] In the second aspect, the present application provides a system for determining ground motion intensity characterization parameters based on the LASSO method, including:

[0024] An independent variable acquisition module, which is used to acquire the regularization method;

[0025] A dependent variable acquisition module, which is used to use the elastic-plastic time history analysis results of ground motion records as the dependent variables of the regularization method;

[0026] ​​The characterization parameter determination module, which is communicatively connected to the independent variable acquisition module and the dependent variable acquisition module, is configured to determine the ground motion intensity characterization parameters of each structural response based on the LASSO method according to the acquired number of dependent variables and independent variables.

[0027] Combined with the second aspect, the independent variable acquisition module includes:

[0028] A recording acquisition unit, configured to acquire ground motion records;

[0029] A parameter acquisition unit, which is communicatively connected to the recording acquisition unit, is configured to extract ground motion parameters from the acquired ground motion records.

[0030] The beneficial effects brought by the technical solution provided by the embodiments of the present application at least include:

[0031] A method for determining ground motion intensity characterization parameters based on the LASSO method provided by the present application selects dependent variables and independent variables, uses the LASSO method to screen ground motion parameters, and determines the characterization parameters of the corresponding ground motion intensity for different structural responses. Description of the Drawings

[0032] Figure 1 It is a schematic flowchart of the method for determining ground motion intensity characterization parameters based on the LASSO method provided by the embodiments of the present application;

[0033] Figure 2 It is a finite element model diagram provided by the embodiments of the present application;

[0034] Figure 3 It is the response spectrum of the ground motion records provided by the embodiments of the present application;

[0035] Figure 4 It is the importance result diagram of ground motion parameters provided by the embodiments of the present application;

[0036] Figure 5 It is a functional module block diagram of the system for determining ground motion intensity characterization parameters based on the LASSO method provided by the embodiments of the present application. Detailed Embodiments

[0037] In order to enable those skilled in the art to better understand the solution of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0038] In the description of the specification, claims and the above-mentioned drawings of this application, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally further includes steps or units not listed, or optionally further includes other steps or units inherent to these processes, methods, products or devices. Descriptions such as "first", "second" and "third" are used to distinguish different objects, etc., and do not represent a sequence, nor do they limit that "first", "second" and "third" are different types.

[0039] In the description of the embodiments of this application, terms such as "exemplary", "for example" or "for instance" are used to represent examples, illustrations or explanations. Any embodiment or design solution described as "exemplary", "for example" or "for instance" in the embodiments of this application should not be construed as being more preferred or having more advantages than other embodiments or design solutions. Rather, the use of words such as "exemplary", "for example" or "for instance" is intended to present relevant concepts in a specific manner.

[0040] In the description of the embodiments of this application, unless otherwise specified, " / " means "or". For example, A / B can mean A or B; "and / or" in the text is merely a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of this application, "a plurality" means two or more than two.

[0041] In some processes described in the embodiments of this application, a plurality of operations or steps appear in a specific order. However, it should be understood that these operations or steps may not be executed in the order in which they appear in the embodiments of this application or may be executed in parallel. The serial numbers of the operations are only used to distinguish different operations, and the serial numbers themselves do not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed in sequence or in parallel, and these operations or steps may be combined.

[0042] In a first aspect, as Figure 1 shown, this application provides a method for determining seismic ground motion intensity characterization parameters based on the LASSO method, including the following steps:

[0043] Step S1: Use seismic ground motion parameters as the independent variable of the regularization method;

[0044] Step S2: Use the elastoplastic time history analysis results of seismic ground motion records as the dependent variable of the regularization method;

[0045] Step S3: Based on the obtained dependent variable and independent variables, determine the ground motion intensity characterization parameters for each structural response using the LASSO method.

[0046] A method for determining ground motion intensity characterization parameters based on the LASSO method provided in this application selects dependent variables and independent variables, and uses the LASSO method to screen ground motion parameters, and determines the corresponding characterization parameters of ground motion intensity for different structural responses.

[0047] In one embodiment, the step S1 of using ground motion parameters as the independent variables of the regularization method specifically includes the following steps:

[0048] Step S11: Obtain ground motion records;

[0049] Step S12: Extract ground motion parameters from the obtained ground motion records. More specifically, this application selects 17 commonly used ground motion parameters for importance analysis. The multivariate ground motion parameters and calculation methods are shown in Table 1:

[0050] Table 1 Multivariate ground motion parameters and calculation methods

[0051]

[0052] Note: PGV in the table ratio is the ratio of the PGV of the remaining waveform signal after extracting the pulse signal to the PGV of the original record; E ratio is the ratio of the energy of the remaining waveform signal to the energy of the original record. When this ratio is greater than 0.85, it is pulse type, and when it is less than 0.15, it is non-pulse type; and are the acceleration and velocity time histories of the ground motion record respectively; S a and S v are the response spectrum acceleration and velocity of the ground motion record respectively; T is the natural vibration period of the structure; t5 and t 95 are the corresponding times when the calculated Arias intensity accounts for 5% and 95% of the calculated Arias intensity at the end of the entire earthquake respectively; T f is the total duration of the ground motion; v0 is the number of times the ground motion acceleration curve passes through zero in unit time.

[0053] In one embodiment, the step S2 of using the elastoplastic time history analysis results of the ground motion record as the dependent variable of the regularization method specifically includes the following steps:

[0054] Step S21: Obtain ground motion records;

[0055] Step S22: Build a finite element model of the structure, which is specifically implemented as:

[0056] This application selects a frame structure in a certain museum located on the Moses Terrace in Luding County for analysis. The frame structure has two floors, with the first floor and the second floor having heights of 4.8m and 4.2m respectively. The general analysis software ANSYS is used to conduct refined modeling of the frame structure, as Figure 2 shown. According to the in-situ rebound test and measurement results, the concrete strength of the frame columns, frame beams, and floor slabs is C30, and the steel bars are HRB400. The strength values of various materials are all standard values. The concrete and steel bars respectively adopt multi-segment and double-segment ideal elastoplastic constitutive relations, both using the isotropic hardening model, and the Bauschinger effect is not considered. The frame beams are modeled using the 3D linear finite strain beam element BEAM188; the floor slabs are modeled using the 3D finite strain shell element SHELL181; to accurately account for the influence of stirrups on the plastic development of frame columns, within the range of 1.5m from the bottom of the first-floor frame columns, the 3D solid element with ribs SOLID65 is used, and the remaining frame columns are simulated using the 3D quadratic finite strain beam element BEAM189; the longitudinal steel bars of the components are all dispersed across the entire cross-section. The hexahedron mapping division is adopted for the solid element part at the lower end of the column, and the mesh is encrypted. The geometric nonlinearity of the frame structure is considered in the elastoplastic time history analysis, and the number of meshes of the frame structure is 26,464.

[0057] Step S23: Input the obtained ground motion records and the finite element model into the finite element analysis software to obtain the elastoplastic time history analysis structural response results of the ground motion records. The response spectrum of the ground motion records used is as Figure 3 shown. The structural responses obtained through analysis are: the maximum inter-story drift angle of the first floor, the maximum inter-story drift angle of the second floor, and the base shear force. The obtained elastic time history analysis structural response results are used as the dependent variables of the regularization method.

[0058] In one embodiment, in step S3, according to the obtained dependent variables and independent variables, the steps of determining the ground motion intensity characterization parameters of each structural response based on the LASSO method specifically include the following steps:

[0059] According to the obtained dependent variables and independent variables, taking the sum of the absolute values of the regression coefficients as the penalty function to compress the regression coefficients, prompting the model to only select important features and reducing the coefficients of other features to zero, so as to achieve the purpose of variable screening.

[0060] In one embodiment, this application uses the base shear force and the maximum inter-story drift as the dependent variables and the ground motion parameters as the independent variables, and adopts the LASSO regularization method to screen the ground motion parameters. The specific algorithm of the LASSO regularization is expressed by the formula:

[0061]

[0062] In the formula, β is the regression coefficient vector β = [β1, β2,..., β n ​T , the β value is used to estimate the importance of ground motion parameters, and the values of each item in the β vector are quantitative indicators of importance: if the corresponding β value is positive, it indicates that the ground motion parameter is positively correlated with the structural response, and vice versa;

[0063] For example: when C is the base shear force, the calculated β is positive, indicating that the base shear force is positively correlated with the structural response;

[0064] For example: when C is the maximum inter-story drift, the calculated β value is negative, indicating that the maximum inter-story drift is negatively correlated with the structural response;

[0065] The above examples of positive and negative correlations are only for illustrative purposes of correlation and do not serve as examples for determining the correct ground motion intensity characterization parameters of structural response;

[0066] In the formula, the larger the absolute value of β, the greater the influence of the ground motion parameter on the structural response. The larger the absolute value of the β value, the greater the influence of the ground motion parameter on the structural response;

[0067] For example: when C is the base shear force, the calculated β is positive, and the larger the positive value, the greater the positive correlation influence of the base shear force on the structural response;

[0068] For example: when C is the maximum inter-story drift, the calculated β value is negative, and the larger the negative value, the greater the negative correlation influence of the maximum inter-story drift on the structural response;

[0069] The above examples of the magnitude correlation of absolute values are only for illustrative purposes and do not serve as examples for determining the correct ground motion intensity characterization parameters of structural response.

[0070] In the formula, C is the base shear force or the maximum inter-story drift, x is the vector of ground motion parameters, x = [x1, x2,..., x n T ; W T β is the penalty function; W T is a vector with values of ±1 for each item, and the sign of each item is the same as the sign of the corresponding item in the β vector; λ is the regularization coefficient, which is used to control the degree of compression of the regression coefficient.

[0071] The importance results of ground motion parameters are as Figure 4 shown. In the present application, the present invention selects the ground motion parameter with the largest β value as the ground motion intensity characterization parameter for the structural response.

[0072] Figure 4 Among them:

[0073] Figure 4 (a) is the importance result diagram of the maximum inter-story drift angle of the first floor; ​

[0074] Figure 4 (b) is the importance result diagram of the maximum inter-story drift angle of the second floor;

[0075] Figure 4 (c) is the importance result diagram of the base shear force.

[0076] In the second aspect, as Figure 5 shown, the present application provides a system for determining the seismic ground motion intensity characterization parameter based on the LASSO method, including an independent variable acquisition module 100, a dependent variable acquisition module 200, and a characterization parameter determination module 300. The independent variable acquisition module 100 is used to acquire the regularization method; the dependent variable acquisition module 200 is used to use the elastoplastic time history analysis result of the seismic ground motion record as the dependent variable of the regularization method; the characterization parameter determination module 300 is communicatively connected to the independent variable acquisition module 100 and the dependent variable acquisition module 200, and is used to determine the seismic ground motion intensity characterization parameter of each structural response based on the LASSO method according to the acquired number of dependent variables and independent variables.

[0077] In an embodiment, the independent variable acquisition module includes a record acquisition unit and a parameter acquisition unit. The record acquisition unit is used to acquire the seismic ground motion record; the parameter acquisition unit is communicatively connected to the record acquisition unit and is used to extract the seismic ground motion parameters from the acquired seismic ground motion record.

[0078] In the third aspect, the embodiment of the present application further provides a readable storage medium.

[0079] The readable storage medium of the present application stores a program for determining the seismic ground motion intensity characterization parameter based on the LASSO method. When the program for determining the seismic ground motion intensity characterization parameter based on the LASSO method is executed by a processor, the steps of the method for determining the seismic ground motion intensity characterization parameter based on the LASSO method as described above are implemented.

[0080] Among them, the method implemented when the program for determining the seismic ground motion intensity characterization parameter based on the LASSO method is executed can refer to each embodiment of the method for determining the seismic ground motion intensity characterization parameter based on the LASSO method of the present application, and will not be elaborated here.

[0081] It should be noted that the serial numbers of the above embodiments of the present application are only for description and do not represent the advantages and disadvantages of the embodiments.

[0082] Through the description of the above embodiments, those skilled in the art can clearly understand that the above-described embodiment methods can be implemented by means of software plus a necessary general hardware platform. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above and includes several instructions for causing a terminal device to execute the methods described in various embodiments of the present application.

[0083] The above are only the preferred embodiments of the present application, and do not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present application, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of the present application.

Claims

1. A method for determining the seismic motion intensity characterization parameter based on the LASSO method, characterized in that, It includes the following steps: Use ground motion parameters as the independent variable of the regularization method; Use the elastoplastic time history analysis results of ground motion records as the dependent variable of the regularization method; Based on the obtained dependent variable and independent variable, determine the ground motion intensity characterization parameters of each structural response based on the LASSO method; The step of determining the ground motion intensity characterization parameters of each structural response based on the LASSO method according to the obtained dependent variable and independent variable specifically includes the following steps: According to the obtained dependent variable and independent variable, use the sum of the absolute values of the regression coefficients as the penalty function to compress the regression coefficients, and use the LASSO regularization method to screen and obtain the ground motion intensity characterization parameters of each structural response; The algorithm formula of the LASSO regularization method is: where β is the regression coefficient vector , the value of β is used to estimate the importance of ground motion parameters; C is the base shear force or the maximum inter-story drift, x is the vector of ground motion parameters, ; is the penalty function; is a vector with each value being ±1, and the sign of each item is the same as the corresponding item in the β vector; λ is the regularization coefficient, which is used to control the degree of regression coefficient compression.

2. The method for determining the seismic motion intensity characterization parameter based on the LASSO method according to claim 1, characterized in that, The step of using ground motion parameters as the independent variable of the regularization method specifically includes the following steps: Obtain ground motion records; Extract ground motion parameters from the obtained ground motion records.

3. The method for determining the seismic motion intensity characterization parameter based on the LASSO method according to claim 1, characterized in that, The step of using the elastoplastic time history analysis results of ground motion records as the dependent variable of the regularization method specifically includes the following steps: Obtain ground motion records; Construct a finite element model of the structure; According to the obtained ground motion records and the finite element model, obtain the elastoplastic time history analysis structural response results of the ground motion records, and use the obtained elastic time history analysis structural response results as the dependent variable of the regularization method.

4. The method for determining the seismic motion intensity characterization parameter based on the LASSO method according to claim 1, characterized in that, When the β value is positive, the ground motion parameter is positively correlated with the structural response; when the β value is negative, the ground motion parameter is negatively correlated with the structural response.

5. The method for determining the seismic motion intensity characterization parameter based on the LASSO method according to claim 1, characterized in that, The larger the absolute value of the β value, the greater the influence of the ground motion parameter on the structural response.

6. A system for determining the seismic motion intensity characterization parameter based on the LASSO method, characterized in that, It includes: An independent variable acquisition module for obtaining the regularization method; A dependent variable acquisition module for using the elastoplastic time history analysis results of ground motion records as the dependent variable of the regularization method; A characterization parameter determination module communicatively connected to the independent variable acquisition module and the dependent variable acquisition module for determining the ground motion intensity characterization parameters of each structural response based on the LASSO method according to the obtained number of dependent variables and independent variables; The step of determining the ground motion intensity characterization parameters of each structural response based on the LASSO method according to the obtained dependent variable and independent variable specifically includes: According to the obtained dependent variable and independent variable, use the sum of the absolute values of the regression coefficients as the penalty function to compress the regression coefficients, and use the LASSO regularization method to screen and obtain the ground motion intensity characterization parameters of each structural response; The algorithm formula of the LASSO regularization method is: In the formula, β is the regression coefficient vector , the value of β is used to estimate the importance of ground motion parameters; C is the base shear force or the maximum inter-story drift, x is the vector of ground motion parameters, ; is the penalty function; is a vector with each value being ±1, and the sign of each item is the same as the sign of the corresponding item in the β vector; λ is the regularization coefficient, which is used to control the degree of regression coefficient compression.

7. The system for determining the seismic motion intensity characterization parameter based on the LASSO method according to claim 6, characterized in that, The independent variable acquisition module includes: A record acquisition unit for obtaining ground motion records; A parameter acquisition unit communicatively connected to the record acquisition unit for extracting ground motion parameters from the obtained ground motion records.

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