Method, medium, and equipment for optimizing the ECC material mix ratio of externally mounted ECC jacketed composite columns.

Abstract

This invention relates to the field of building engineering technology, specifically to a method, medium, and equipment for optimizing the mix proportion of ECC materials in externally fitted ECC-clad composite columns. The method includes: establishing a dataset containing multiple sets of ECC mix proportions; establishing an optimal machine learning prediction model; calculating a performance index using the normalized characteristics of ECC tensile strength and tensile strain, and the weighted normalization coefficients of ECC tensile strain and tensile strength; and characterizing the selection of the ECC mix proportion based on the performance index. This invention solves the problem of ECC mix proportion selection in engineering relying on experience and lacking quantitative guidance, realizing a shift from experience-based decision-making to scientific optimization. It combines machine learning, structural mechanics, and multi-objective decision-making to achieve accurate prediction of ECC material properties.

Description

Technical Field

[0001] This invention relates to the field of building engineering technology, and in particular to a method, medium and equipment for optimizing the ECC material mix ratio of an externally mounted ECC jacketed composite column. Background Technology

[0002] In structural engineering design, seismic performance is always a crucial factor, especially in locations with extremely high requirements for safety and functionality, such as energy infrastructure, underground transportation hubs, and large public buildings. Columns in frame structures, acting as the "link" connecting the superstructure and foundation, directly affect the overall seismic safety of the structure due to their load-bearing capacity and deformation performance; their importance is self-evident.

[0003] In recent years, cement-based composite materials for engineering applications have gained increasing attention in structural ductility design due to their superior mechanical properties. These materials not only possess tensile strengths exceeding 10 MPa but also tensile strain capacity exceeding 10%, significantly improving the deformation and damage behavior of components under stress. Among them, ECC jackets, as a typical application in column members, can effectively enhance the seismic toughness and damage control capabilities of columns.

[0004] However, the material cost of ECC (Engineered Cementitious Composite, a cement-based composite material with high toughness) is currently about 10-20 times that of ordinary concrete. In engineering projects, the selection of ECC mix proportions relies on experience and lacks quantitative guidance, which to some extent limits its large-scale promotion. Therefore, how to strike a balance between ensuring seismic safety and economic feasibility has become a key issue that needs careful consideration in the selection and application of ECC in engineering projects. Summary of the Invention

[0005] The main objective of this invention is to provide a method, medium, and equipment for optimizing the ECC material mix ratio in an externally mounted ECC jacketed composite column, aiming to solve the technical problem that the selection of ECC mix ratio in existing engineering projects relies on experience and lacks quantitative guidance.

[0006] To achieve the above objectives, the present invention proposes a method for optimizing the ECC material mix ratio of an external ECC jacketed composite column, comprising the following steps:

[0007] S1. Establish a dataset including multiple ECC mix proportions. The dataset contains the components of each ECC mix proportion, the compressive strength, tensile strength and tensile strain of the ECC.

[0008] S2. Establish the optimal machine learning prediction model;

[0009] S3. For known column members, when selecting the ECC mix proportion based on the machine learning prediction model, determine the compressive strength range of ECC.

[0010] S4. Based on the compressive strength range of ECC in S3, obtain the range of tensile strength and tensile strain of ECC; construct a peak strength calculation model for the external ECC jacketed composite column.

[0011] S5. Using the fixed tensile strength within the range of tensile strength of ECC in S4 as a benchmark, fit the functional relationship between the strain value and the corresponding column strength, and calculate the tensile strain weighting coefficient based on the functional relationship between the strain value and the corresponding column strength; using the fixed tensile strain within the range of tensile strain of ECC in S4 as a benchmark, fit the functional relationship between the strength value and the corresponding column bearing capacity; calculate the tensile strength weighting coefficient based on the functional relationship between the strength value and the corresponding column bearing capacity.

[0012] S6. Calculate the weighted normalization coefficients of tensile strain and tensile strength of ECC using the tensile strain weighting coefficient and tensile strength weighting coefficient.

[0013] S7. The tensile strength and tensile strain of each ECC mix proportion group were standardized and quantitatively processed. By constructing a comparison matrix, the normalized characteristics of ECC tensile strength and tensile strain were obtained. The performance index was calculated by using the normalized characteristics of ECC tensile strength and tensile strain and the weighted normalization coefficients of ECC tensile strain and tensile strength.

[0014] S8. Select the optimal ECC ratio based on the performance index.

[0015] The improvement of the method for optimizing the ECC material mix ratio of the externally ECC-jacketed composite column of the present invention lies in the following steps when constructing the peak strength calculation model of the externally ECC-jacketed composite column:

[0016] Based on the linear relationship of the cross section, the stress of the reinforcing steel The expression is as follows:

[0017] ;

[0018] The force balance equations and bending moment balance equations for the cross-section are established separately to obtain the peak strength of the ECC-jacketed composite column, i.e.:

[0019] ;

[0020] ;

[0021] ;

[0022] in, The elastic modulus of the reinforcing steel bar. This represents the strain of the reinforcing steel at different locations on the beam cross-section. It is an axial force; The stress of the reinforcing steel at different locations on the beam cross-section; This represents the cross-sectional area of ​​the reinforcing steel. For the resultant force of concrete; The resultant force of the ECC portion between the outer edge of the ordinary concrete and the neutral axis of the cross section; The resultant force is the ECC portion outside the outer edge of the ordinary concrete. and This is the distance from the resultant force of all component forces to the bending moment reference point; The distance from the horizontal axial force to the bottom of the column; Peak intensity This represents the peak bending moment.

[0023] The improvement in the optimal ECC material mix ratio method for the external ECC jacketed composite column of the present invention lies in that the tensile strength range of the ECC is [missing information]. The range of tensile strain is ;

[0024] With ECC fixed tensile strength Based on, in to Input ten equally spaced strain values ​​within the range, and fit the functional relationship between the ten equally spaced strain values ​​and the corresponding column strength. ;

[0025] The steps for calculating the tensile strain weighting coefficient are as follows:

[0026] For tensile strain changes, the calculation function is... The area enclosed by the constant bearing capacity of the columns without ECC for:

[0027] ;

[0028] in, This represents the constant bearing capacity of a column without ECC.

[0029] ;

[0030] ;

[0031] and The average is the tensile strain weighting coefficient. ;

[0032] in, The tensile strength of ECC is The weighting coefficients, The tensile strength of ECC is The weighting coefficients, This represents the tensile strength of the ECC.

[0033] The improvement of the method for optimizing the ECC material mix ratio of the external ECC jacketed composite column of the present invention lies in using the fixed tensile strain of the ECC. Based on, in to Input ten equally spaced strength values ​​within the range, and fit the functional relationship between the ten equally spaced strength values ​​and the corresponding column bearing capacity. ;

[0034] The steps for calculating the tensile strength weighting coefficient are as follows:

[0035] For changes in tensile strength, the calculation function is... The area enclosed by the constant bearing capacity of the columns without ECC is :

[0036] ;

[0037] ;

[0038] ;

[0039] and The average is the tensile strength weighting coefficient. ;

[0040] in, The tensile strain of ECC is The weighting coefficients, The tensile strength of ECC is The weighting coefficients, The tensile strain of ECC.

[0041] The improvement of the method for optimizing the ECC material mix ratio of the external ECC jacketed composite column of the present invention lies in the following formula when calculating the weighted normalization coefficients of the tensile strain and tensile strength of the ECC:

[0042] , ;

[0043] That is, we get:

[0044] ;

[0045] in: The weighted normalization coefficients for the tensile strain of ECC. This is the weighted normalization coefficient for the tensile strength of ECC.

[0046] The improvement of the method for optimizing the ECC material mix ratio of the external ECC jacketed composite column of the present invention lies in the following steps when standardizing and quantifying the tensile strength and tensile strain of each ECC mix ratio group, and obtaining the normalized characteristics of ECC tensile strength and tensile strain by constructing a comparison matrix:

[0047] The tensile strength and tensile strain of each ECC mixture were normalized and quantified.

[0048] Construct a comparison matrix, where the i-th row and i-th column are... The elements of a column are denoted as Taking the first column of the tensile strength comparison matrix as an example, The tensile strength of all the proportions here must be arranged in a fixed order, and the corresponding comparison matrix... Represented as:

[0049] ;

[0050] The tensile strength or tensile strain quantification characteristic value of a single mix proportion is expressed as follows:

[0051] ;

[0052] in, These represent the first row to the second row of the comparison matrix, respectively. Elements in each row and column; This indicates the first row to the second row of the comparison matrix. The eigenvalues ​​of the rows represent the product and root of each row. Power; The symbol for multiplication;

[0053] Normalize each eigenvalue; that is, normalize the eigenvalues ​​of each group. It is given by the following formula:

[0054] ;

[0055] in, To compare the eigenvalues ​​of a specific row in the matrix, the normalized eigenvalues ​​of the ECC tensile strength and tensile strain are respectively... and .

[0056] The improvement of the method for optimizing the ECC material mix ratio of the external ECC jacketed composite column of the present invention lies in the performance index. The calculation formula is as follows:

[0057] .

[0058] The improvement of the method for optimizing the ECC material mix ratio of the external ECC jacketed composite column of the present invention is that, in step S1, the compressive strength of the ECC is obtained by measuring a cubic specimen, and the tensile strength and tensile strain are obtained by measuring a standard specimen.

[0059] The present invention also provides a readable storage medium storing a computer program adapted to be loaded by a processor and executed as described above for the method of optimizing the ECC material mix ratio of the external ECC jacket assembly column.

[0060] The present invention also provides a computer device, the computer device including a memory and a processor, the memory storing a computer program, which, when executed by the processor, performs the ECC material proportioning optimization method for the external ECC jacketed assembly column as described above. The technical solution of the present invention has the following beneficial effects:

[0061] The present invention provides a systematic, data-driven method for optimizing the ECC material mix proportion of externally fitted ECC-coated composite columns. This method effectively solves the problem of relying on experience and lacking quantitative guidance in ECC mix proportion selection in engineering, realizing a shift from experience-based decision-making to scientific optimization. Through techniques such as SHAP analysis, it reveals key components affecting ECC performance (such as cement, water-cement ratio, silica fume, and fiber elongation at break), providing clear guidance for mix proportion design and adjustment. By establishing a component mechanical model, it quantitatively analyzes the contribution weight of different tensile properties (strength, strain) to the improvement of the overall bearing capacity of the composite column. and This elevates the evaluation criteria from the material level to the structural performance level; ultimately, a performance index ( As a unified and quantitative selection index, The mix proportion with the highest value is the mix proportion that is most conducive to improving the seismic performance of the target component, making the selection process objective and comparable. This invention combines machine learning, structural mechanics and multi-objective decision-making, which not only realizes the accurate prediction of ECC material properties, but more importantly, establishes a quantitative optimization method for ECC mix proportions that is directly guided by improving the seismic performance of the final structural components. It has important theoretical innovation value and engineering application prospects. Attached Figure Description

[0062] 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 the structures shown in these drawings without creative effort.

[0063] Figure 1 This is a flowchart of the method for optimizing the ECC material mix ratio of the external ECC jacketed composite column of the present invention. Detailed Implementation

[0064] 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 a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0065] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0066] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0067] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0068] like Figure 1 As shown, this invention proposes a method for optimizing the ECC material mix ratio in an external ECC jacketed composite column, comprising the following steps:

[0069] S1. Establish a dataset including multiple ECC mix proportions. The dataset contains the components of each ECC mix proportion, the compressive strength, tensile strength and tensile strain of the ECC.

[0070] Each ECC mix proportion component includes: cement, water, silica sand, other sand, coarse aggregate, fiber volume content, fiber weight, water-cement ratio, total mineral admixtures, silica fume, slag, fly ash, other active mineral admixtures (such as crushed glass powder, rice husk ash, etc.), water-reducing agent, fiber diameter, fiber length, fiber elongation at break, and fiber tensile strength.

[0071] The ECC compressive strength was obtained by measuring a 100×100×100mm cubic specimen, and the tensile strength and tensile strain were obtained by measuring a standard "dog bone" specimen. The measurement age for these mechanical properties was 28 days.

[0072] S2. The hyperparameters of the machine learning model are optimized through random search and Fourier optimization. The optimal machine learning prediction model is established through Pearson analysis, prediction accuracy analysis, and SHAP analysis (all existing analysis methods). The optimal machine learning model selected is the CatBoost algorithm (Yandex's open-source gradient boosting decision tree algorithm), which can achieve a prediction accuracy of over 0.95 for compressive strength, tensile strength, and tensile strain.

[0073] The SHAP analysis in the CatBoost algorithm model shows that the factors that contribute most to the material properties of ECC materials are cement, water-cement ratio, silica fume, and fiber elongation at break.

[0074] S3. For known column members, when selecting the ECC mix proportion based on a machine learning prediction model, determine the compressive strength range of the ECC; specifically, for known column members, the compressive strength of their ordinary concrete can be obtained ( While increasing the compressive strength of ECC has limited effect on improving the seismic performance of external ECC-jacketed composite columns, excessively low compressive strength can negatively impact the effectiveness of the external ECC jacket. Therefore, in this study, when selecting the ECC mix proportion based on machine learning, the compressive strength of the ECC was determined to be [value missing]. ±3MPa;

[0075] S4. Based on the ECC compressive strength range in S3, approximately... The proportion of the ingredients, The range of ECC tensile strength in the mix proportion is as follows: The range of tensile strain is A peak strength calculation model for an externally ECC-jacketed composite column was constructed. In the calculation model, the compressive strength of the ECC was fixed at [value missing]. ;

[0076] When constructing the peak strength calculation model for the externally ECC-clad composite column, the mechanical model is based on a plane section. When the ECC-clad composite column reaches its peak strength, the outer edge of the ordinary concrete column reaches its ultimate compressive strain. Considering the constraint effect of the ECC cladding, this strain is taken as 0.04. The stress of the reinforcing steel... The expression is as follows:

[0077] ;

[0078] The force balance equations and bending moment balance equations for the cross-section are established separately to obtain the peak strength of the ECC-jacketed composite column, i.e.:

[0079] ;

[0080] ;

[0081] ;

[0082] in, The elastic modulus of the reinforcing steel bar. This represents the strain of the reinforcing steel at different locations on the beam cross-section. It is an axial force; The stress of the reinforcing steel at different locations on the beam cross-section; This represents the cross-sectional area of ​​the reinforcing steel. For the resultant force of concrete; The resultant force of the ECC portion between the outer edge of the ordinary concrete and the neutral axis of the cross section; The resultant force is the ECC portion outside the outer edge of the ordinary concrete. and This is the distance from the resultant force of all component forces to the bending moment reference point; The distance from the horizontal axial force to the bottom of the column; Peak intensity This represents the peak bending moment.

[0083] S5. Using the fixed tensile strength within the range of tensile strength of ECC in S4 as a benchmark, fit the functional relationship between the strain value and the corresponding column strength, and calculate the tensile strain weighting coefficient based on the functional relationship between the strain value and the corresponding column strength.

[0084] With ECC fixed tensile strength Based on, in to Input ten equally spaced strain values ​​within the range, and fit the functional relationship between the ten equally spaced strain values ​​and the corresponding column strength. ;

[0085] The steps for calculating the tensile strain weighting coefficient are as follows:

[0086] For tensile strain changes, the calculation function is... The area enclosed by the constant bearing capacity of the columns without ECC for:

[0087] ;

[0088] in, This represents the constant bearing capacity of a column without ECC.

[0089] ;

[0090] ;

[0091] and The average is the tensile strain weighting coefficient. ;

[0092] in, The tensile strength of ECC is The weighting coefficients, The tensile strength of ECC is The weighting coefficients, This represents the tensile strength of the ECC.

[0093] Using the fixed tensile strain within the tensile strain range of ECC in S4 as a benchmark, a functional relationship between the strength value and the corresponding column bearing capacity is fitted; the tensile strength weighting coefficient is calculated based on the functional relationship between the strength value and the corresponding column bearing capacity.

[0094] With ECC fixed tensile strain Based on, in to Input ten equally spaced strength values ​​within the range, and fit the functional relationship between the ten equally spaced strength values ​​and the corresponding column bearing capacity. ;

[0095] The steps for calculating the tensile strength weighting coefficient are as follows:

[0096] For changes in tensile strength, the calculation function is... The area enclosed by the constant bearing capacity of the columns without ECC is :

[0097] ;

[0098] ;

[0099] ;

[0100] and The average value is the tensile strength weighting coefficient;

[0101] in, The tensile strain of ECC is The weighting coefficients, The tensile strength of ECC is The weighting coefficients, The tensile strain of ECC.

[0102] S6. The weighted normalization coefficients for tensile strain and tensile strength of ECC are calculated using the tensile strain weighting coefficient and tensile strength weighting coefficient, as shown in the following formula:

[0103] , ;

[0104] That is, we get:

[0105] ;

[0106] in: The weighted normalization coefficients for the tensile strain of ECC. This is the weighted normalization coefficient for the tensile strength of ECC.

[0107] S7. The tensile strength and tensile strain of each ECC mix proportion group were standardized and quantitatively processed. By constructing a comparison matrix, the normalized characteristics of ECC tensile strength and tensile strain were obtained. The performance index was calculated using the normalized characteristics of ECC tensile strength and tensile strain and the weighted normalization coefficients of ECC tensile strain and tensile strength. The specific steps are as follows:

[0108] The tensile strength and tensile strain of each ECC mixture were normalized and quantified.

[0109] Construct a comparison matrix, the first of which is... Line number The elements of a column are denoted as Taking the first column of the tensile strength comparison matrix as an example, The tensile strength of all the proportions here must follow a fixed order, and the corresponding comparison matrix is ​​expressed as follows:

[0110] ;

[0111] in, To compare the first in the matrix Line number Column elements;

[0112] The tensile strength or tensile strain quantification characteristic value of a single mix proportion is expressed as follows:

[0113] ;

[0114] in, These represent the first row to the second row of the comparison matrix, respectively. Elements in each row and column; This indicates the first row to the second row of the comparison matrix. n The eigenvalues ​​of the rows represent the product and root of each row. n The power is the same as the row number; The symbol for multiplication;

[0115] Normalize each eigenvalue; that is, normalize the eigenvalues ​​of each group. It is given by the following formula:

[0116] ;

[0117] in, To compare the eigenvalues ​​of a specific row in the matrix, the normalized eigenvalues ​​of the ECC tensile strength and tensile strain are respectively... and .

[0118] The formula for calculating the performance index is as follows:

[0119] .

[0120] S8. Select the optimal ECC mix ratio based on the performance index. The higher the value, the more suitable the corresponding ECC mix proportion is for practical engineering applications.

[0121] The present invention also provides a readable storage medium storing a computer program adapted to be loaded by a processor and executed as described above for the method of optimizing the ECC material mix ratio of the external ECC jacket assembly column.

[0122] The present invention also provides a computer device, the computer device including a memory and a processor, the memory storing a computer program, the computer program being executed by the processor to run the method for optimizing the ECC material mix ratio of the external ECC jacketed composite column as described above.

[0123] This invention provides specific application examples of column specimens, including the following:

[0124] Step 1: The specific structural and material parameters of the column specimen are as follows: The column cross-section is 300mm × 300mm, the external sleeve height is 400mm, and the thickness is 25mm. The column contains 12 longitudinal reinforcing bars, each with a diameter of 12mm and a strength grade of HRB400. The stirrup spacing is 50mm, the stirrup diameter is 6mm, and each direction has four-legged stirrups, with a stirrup strength grade of HRB400. Additionally, the concrete strength grade is C30. The test uses displacement control to apply horizontal loads, with each loading increment being 7mm, and each loading cycle repeated 3 times until a load of 63mm is reached, while maintaining a constant vertical axial force of 200kN. The horizontal load is applied 1200mm from the bottom of the column.

[0125] Step 2: Based on the above conditions, the compressive strength of the concrete... The measured compressive strength was 35.1 MPa, and based on this, the selected ECC compressive strength range was 32.1 MPa to 38.1 MPa. Based on this strength range, 10 mix proportions were selected and are listed in Table 1.

[0126] Table 1. Mix proportions of 10 ECC materials (content per cubic meter, unit: kg)

[0127]

[0128] Step 3: Based on the tensile strength and tensile strain range of these 10 mix proportions, the weighting coefficients of tensile strength and tensile strain were calculated respectively. The normalized weighting coefficients of tensile strength and tensile strain were 0.52 and 0.48 respectively.

[0129] Step 4: The normalized eigenvalues ​​of tensile strength and tensile strain for these ten mix proportions were calculated. The comparison matrix of tensile strength and tensile strain is shown below. The calculated normalized eigenvalues ​​and... The values ​​are shown in Table 2:

[0130] ;

[0131] .

[0132] Table 2. Normalized eigenvalues ​​of ten combination ratios and value

[0133]

[0134] By comparing the above Therefore, the first group of mixing proportions is the preferred mixing proportion. Among them, This is a comparison matrix of ECC tensile strength. This is the comparison matrix for ECC tensile strain.

[0135] The above description is only a preferred embodiment of the present invention and does not limit the scope of the present invention. All equivalent structural transformations made using the contents of the present invention under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the protection scope of the present invention.

Claims

1. A method for optimizing the ECC material mix ratio in an externally mounted ECC jacketed composite column, characterized in that, Includes the following steps: S1. Establish a dataset including multiple ECC mix proportions. The dataset contains the components of each ECC mix proportion, the compressive strength, tensile strength and tensile strain of the ECC. S2. Establish the optimal machine learning prediction model; S3. For known column members, when selecting the ECC mix proportion based on the machine learning prediction model, determine the compressive strength range of ECC. S4. Based on the compressive strength range of ECC in S3, obtain the range of tensile strength and tensile strain of ECC; construct a peak strength calculation model for the external ECC jacketed composite column. S5. Using the fixed tensile strength within the range of tensile strength of ECC in S4 as a benchmark, fit the functional relationship between the strain value and the corresponding column strength, and calculate the tensile strain weighting coefficient based on the functional relationship between the strain value and the corresponding column strength. Using the fixed tensile strain within the tensile strain range of ECC in S4 as a benchmark, a functional relationship between the strength value and the corresponding column bearing capacity is fitted; the tensile strength weighting coefficient is calculated based on the functional relationship between the strength value and the corresponding column bearing capacity. S6. Calculate the weighted normalization coefficients of tensile strain and tensile strength of ECC using the tensile strain weighting coefficient and tensile strength weighting coefficient. S7. The tensile strength and tensile strain of each ECC mix proportion group were standardized and quantitatively processed. By constructing a comparison matrix, the normalized characteristics of ECC tensile strength and tensile strain were obtained. The performance index was calculated by using the normalized characteristics of ECC tensile strength and tensile strain and the weighted normalization coefficients of ECC tensile strain and tensile strength. S8. Select the optimal ECC ratio based on the performance index.

2. The method for optimizing the ECC material mix ratio of the external ECC jacketed composite column according to claim 1, characterized in that, The peak strength calculation model for externally ECC-jacketed composite columns includes the following steps: Based on the linear relationship of the cross section, the stress of the reinforcing steel The expression is as follows: ； The force balance equations and bending moment balance equations for the cross-section are established separately to obtain the peak strength of the ECC-jacketed composite column, i.e.: ； ； ； in, This refers to the elastic modulus of the reinforcing steel. This represents the strain of the reinforcing steel at different locations on the beam cross-section. It is an axial force; The stress in the reinforcing steel at different locations on the beam cross-section; This represents the cross-sectional area of ​​the reinforcing steel. For the resultant force of concrete; The resultant force of the ECC portion between the outer edge of the ordinary concrete and the neutral axis of the cross section; The resultant force is the ECC portion outside the outer edge of the ordinary concrete. and This is the distance from the resultant force of all component forces to the bending moment reference point; The distance from the horizontal axial force to the bottom of the column; Peak intensity This represents the peak bending moment.

3. The method for optimizing the ECC material mix ratio of the external ECC jacketed composite column according to claim 1, characterized in that, The tensile strength range of ECC is The range of tensile strain is ; With ECC fixed tensile strength Based on, in to Input ten equally spaced strain values ​​within the range, and fit the functional relationship between the ten equally spaced strain values ​​and the corresponding column strength. ; The steps for calculating the tensile strain weighting coefficient are as follows: For tensile strain changes, the calculation function is... The area enclosed by the constant bearing capacity of the columns without ECC for: ； in, This represents the constant bearing capacity of a column without ECC. ； ； and The average is the tensile strain weighting coefficient. ; in, The tensile strength of ECC is The weighting coefficients, The tensile strength of ECC is The weighting coefficients, This represents the tensile strength of the ECC.

4. The method for optimizing the ECC material mix ratio of the external ECC jacketed composite column according to claim 3, characterized in that, With ECC fixed tensile strain Based on, in to Input ten equally spaced strength values ​​within the range, and fit the functional relationship between the ten equally spaced strength values ​​and the corresponding column bearing capacity. ; The steps for calculating the tensile strength weighting coefficient are as follows: For changes in tensile strength, the calculation function is... The area enclosed by the constant bearing capacity of the columns without ECC is : ； ； ； and The average is the tensile strength weighting coefficient. ; in, The tensile strain of ECC is The weighting coefficients, The tensile strength of ECC is The weighting coefficients, The tensile strain of ECC.

5. The method for optimizing the ECC material mix ratio of the external ECC jacketed composite column according to claim 4, characterized in that, The weighted normalization coefficients for tensile strain and tensile strength of ECC are calculated using the following formula: ， ； That is, we get: ； in: The weighted normalization coefficients for the tensile strain of ECC are... This is the weighted normalization coefficient for the tensile strength of ECC.

6. The method for optimizing the ECC material mix ratio of the external ECC jacketed composite column according to claim 5, characterized in that, The tensile strength and tensile strain of each ECC mix proportion group were standardized and quantified. The normalized characteristics of ECC tensile strength and tensile strain were obtained by constructing a comparison matrix, including the following steps: The tensile strength and tensile strain of each ECC mixture were normalized and quantified. Construct a comparison matrix, where the i-th row and i-th column are... The elements of a column are denoted as Taking the first column of the tensile strength comparison matrix as an example, The tensile strength of all the proportions here must be arranged in a fixed order, and the corresponding comparison matrix... Represented as: ； in, To compare the first in the matrix Line number Column elements; The tensile strength or tensile strain quantification characteristic value of a single mix proportion is expressed as follows: ； in, These represent the first to the last rows of the comparison matrix. Elements in each row and column; This indicates the first row to the second row of the comparison matrix. The eigenvalues ​​of the rows represent the product and root of each row. Power; The symbol for multiplication; Normalize each eigenvalue; that is, normalize the eigenvalues ​​of each group. It is given by the following formula: ； in, To compare the eigenvalues ​​of a specific row in the matrix, the normalized eigenvalues ​​of the ECC tensile strength and tensile strain are respectively... and .

7. The method for optimizing the ECC material mix ratio of the external ECC jacketed composite column according to claim 6, characterized in that, Performance Index The calculation formula is as follows: 。 8. The method for optimizing the ECC material mix ratio of the external ECC jacketed composite column according to claim 1, characterized in that, In step S1, the compressive strength of the ECC is obtained by measuring a cubic specimen, and the tensile strength and tensile strain are obtained by measuring a standard specimen.

9. A readable storage medium, characterized in that, The readable storage medium stores a computer program that is adapted to be loaded by a processor and executed by the processor to optimize the ECC material mix ratio of the external ECC jacketed assembly column according to any one of claims 1-8.

10. A computer device, characterized in that, The computer device includes a memory and a processor. The memory stores a computer program. When the computer program is executed by the processor, it runs the method for optimizing the ECC material mix ratio of the external ECC jacketed composite column as described in any one of claims 1-8.

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