Numerical calculation method for compression bearing and deformation of high-strength reinforced concrete column

Abstract

The invention relates to the field of buildings, in particular to a high-strength reinforced concrete column compression bearing and deformation numerical calculation method which comprises the following steps: S1, continuously changing strain values of a high-strength reinforced concrete column body far away from an axial force side and an adjacent axial force side, the strain of each side far away from the axial force and the strain of the adjacent axial force side form a group of strain pairs; s2, the axial force, the bending moment and the curvature borne by the section of the cylinder in the corresponding state are inversely calculated according to the strain pair; s3, effective strain pairs are screened, and the remaining strain pair data are optimized to serve as a data set; and S4, calculating the ultimate bearing capacity or lateral deformation displacement of the cylinder in different states according to the data set. The invention provides the accurate and efficient calculation method for calculating the ultimate bearing capacity and the lateral deformation displacement of the high-strength steel bar eccentric compression cylinder.

Description

Technical Field

[0001] The invention relates to the field of construction, and in particular to a numerical calculation method for compressive bearing and deformation of a high-strength reinforced concrete column. Background Art

[0002] As the most important material in concrete structures, steel bars are consumed in huge quantities in various infrastructure construction activities. In order to reduce the consumption of steel bars to meet the requirements of green and low-carbon development in the construction industry, a large number of high-strength steel bars have been introduced in the construction field. Since high-strength steel bars have higher yield strength and tensile strength, the required steel bar cross-sectional area is smaller under the same structural bearing capacity requirements. For this reason, in China, 500MPa high-strength steel bars have been included in the "Concrete Structure Design Code" (GB 50010-2010 (2015 Edition)), and their use is encouraged when possible.

[0003] With the increasing popularity of high-strength steel bars in actual engineering, the use of high-strength steel bar eccentrically compressed columns has become increasingly widespread. For the eccentric compression design of high-strength steel bar eccentrically compressed columns, it is often necessary to use ABAQUS software in combination with material nonlinearity, geometric nonlinearity (large deformation) and boundary conditions to calculate the ultimate bearing capacity and specific values ​​of lateral deformation displacement of the high-strength steel bar eccentrically compressed columns. The software calculation has many parameter settings, high requirements for the computing platform, long calculation time, and insufficient efficiency, so it needs to be solved urgently. Summary of the invention

[0004] In order to avoid and overcome the technical problems existing in the prior art, the present invention provides a numerical calculation method for the compressive bearing and deformation of high-strength reinforced concrete columns. The present invention provides an accurate and efficient calculation method for calculating the ultimate bearing capacity and lateral deformation displacement of high-strength reinforced eccentrically compressed columns.

[0005] To achieve the above object, the present invention provides the following technical solutions: A numerical calculation method for compressive bearing and deformation of a high-strength reinforced concrete column comprises the following steps: S1, continuously changing the strain values ​​of the high-strength steel bar eccentric column away from the axial force side and the adjacent axial force side, each strain away from the axial force side and the strain adjacent to the axial force side constitute a set of strain pairs; S2. Inversely calculate the axial force, bending moment and curvature of the column section under the corresponding state according to the strain; S3, screening effective strain pairs, and optimizing the remaining strain pair data as a data set; S4. Calculate the ultimate bearing capacity or lateral deformation displacement of the column under different conditions based on the data set.

[0006] As a further solution of the present invention: in step S2, the cross section of the column is evenly divided into Q After each strip, the strain pairs are numerically integrated to calculate the axial force, bending moment and curvature of the cylinder section in the state corresponding to each strain pair. ; in, N It represents the axial force on the column section; M represents the bending moment on the column section; represents the curvature of the cylinder section; It means that under the action of strain, the j The corresponding stress of the column at the strip dividing line is: j The value range is 1, 2, 3, ..., Q -1, Q ; It means that under the action of strain, the j+1 The corresponding stress of the column at each strip dividing line; b Indicates the width of the column section; h Indicates the height of the column section; It means that under the action of strain, j The vertical distance between the center of each strip and the geometric center axis of the column section; It means that under the action of strain, the column p Axial force on the root longitudinal reinforcement; U represents the total number of longitudinal reinforcements in the column, p The value range is 1, 2, 3, ..., U－1 , U ; It means that under the action of strain, the column p The vertical distance between the root longitudinal reinforcement and the geometric center axis of the column section; represents the strain on the side of the strain pair away from the axial force; Represents the strain on the adjacent axial force side of a strain pair.

[0007] As a further solution of the present invention: in step S3: S31, N, M, As the coordinate axis, a spatial rectangular coordinate system is constructed with each strain pair corresponding to ( N , M , ) as a point in a spatial rectangular coordinate system; S32, delete the space rectangular coordinate system N or M For points in the negative state, project the remaining points to NoM On the plane, NoM The envelope of the projection points of each point in the plane is used as the cross section of the cylinder. NM curve; S33, NM The curvature of each point on the curve is the reference curvature, when any strain is N Value and NM On the curve N The values ​​are equal, and the curvature of the strain pair When it is greater than the base curvature, the strain pair is deleted; S34, will NoM The residual strain is optimized after plane meshing.

[0008] As a further solution of the present invention: in step S34, NoM In the plane, M is the horizontal axis, N is the vertical axis, NoM Perform grid division to form a partitioned grid; construct a computational grid with the nodes of the partitioned grid as the center, and the size and shape of the computational grid correspond to the size and shape of the partitioned grid. Inverse calculation using plane interpolation within the computational grid : ; in, It represents the maximum axial compressive bearing capacity of the high-strength steel bar eccentric compression column; It represents the maximum bending moment of the high-strength steel bar eccentrically loaded column; Indicates the number of columns that the grid is divided into vertically; Indicates the number of rows of grid divisions along the horizontal direction; Indicates the vertical step length of a single grid; Indicates the horizontal step size of a single grid; Indicates that the grid is divided into n List m The strain at the row node is related to the curvature of the corresponding column section; express n List m The total amount of strain pairs in the computational grid corresponding to the row node; Indicates the number of The curvature of the cylindrical section corresponding to each strain pair.

[0009] As a further solution of the present invention: S41, after determining the axial force on the column, calculate the lateral deformation displacement of the column: S411, along the height direction of the column, divide the column into k segment, thus forming a k+1 The lateral deformation displacement at the interface boundary is: ; in, Indicates the column +1 The lateral deformation displacement at the interface boundary; Indicates the column The lateral deformation displacement at the interface boundary; Indicates the column －1 The lateral deformation displacement at the interface boundary; The value range is 1, 2, 3, ..., k , k+1 ; Represents the spacing between adjacent interfaces; Indicates the subject The curvature of the interface is calculated according to step S34; S412, the first interface of the cylinder and the k+1 The lateral deformation displacement value of the first interface is 0, the second interface is taken as the starting interface, and a lateral deformation displacement value is assigned to the second interface. , The value assigned to -6 ; S413, based on the axial force on the column, the initial eccentricity of the column and the assumed lateral displacement value of the second interface Calculate the current bending moment at the second interface ; S414: Calculate the lateral deformation displacement value of the third interface of the column according to step S411 ; S415. Calculate the lateral deformation displacement values ​​of all interfaces of the column in sequence and record the k+1 The lateral deformation displacement value of the interface ; S416, gradually expand the step S412 , repeat steps S413 to S415 until the calculated and the value obtained in step S415 When the sign is opposite, the output ; S417: According to the output in step S416 , the true lateral displacement value of the second interface is gradually obtained through the dichotomy method, thus obtaining the lateral deformation displacement curve of the column under the action of a certain axial force.

[0010] As a further solution of the present invention: when calculating the maximum lateral displacement deformation of the column, the cross section of the column is NM The curve is processed equivalently to obtain the cylinder curve, is the cross section of the cylinder under axial force The maximum lateral displacement deformation value allowed under the action; ; in, It represents the axial force to which the column section is subjected when it reaches its ultimate bearing capacity; It represents the bending moment to which the column section is subjected when it reaches its ultimate bearing capacity; Represents the initial eccentricity of the cylinder.

[0011] As a further solution of the present invention: S42, calculating the ultimate bearing capacity of the column under biased compression: S421, given initial axial pressure of the cylinder along the axial direction N 0 as well as N 1 , N 0 < N 1 , calculated according to step S41 N 0 as well as N 1 The lateral displacement deformation value of the column under the axial pressure d 0 as well as d 1 ; S422, connection ( d 0 ,N 0 )and( d 1 , N 1 ) forms a straight line with Nf The curves intersect at ( d 2 , ); S423, calculate the lateral displacement deformation value of the column in the column d 2 The corresponding axial force N 2 ; S424、( d 0 , N 0 )and( d 1 , N 1 ) are replaced by ( d 1 , N 1 )and( d 2 , N 2 ), repeat steps S422 to S423, and calculate ( d 3 , N 3 )and( d 3 , ), d 4 , N 4 )and( d 4 , ),…,( d i , N i )and( d i , ); S425, comparison and judgment and The value of and When the absolute difference is less than the set value, the output is the ultimate bearing capacity of the column.

[0012] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention provides an efficient and accurate numerical calculation method for predicting the compressive bearing and deformation capacity of high-strength reinforced concrete columns, based on full consideration of the nonlinear properties of high-strength steel bars and concrete materials and the geometric nonlinearity presented during the compression process of eccentrically compressed columns; solves the problems of poor calculation accuracy and low calculation efficiency of graphical methods; solves the problems of traditional commercial general finite element calculation programs, such as many parameter settings, high requirements for the computing platform, long calculation time, high calculation cost, and high requirements for engineering and technical personnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the strain on the side away from the axial force and the strain on the side adjacent to the axial force in the present invention.

[0014] Figure 2 It is a schematic diagram of the combination of strain pairs in the present invention.

[0015] Figure 3 This is a schematic diagram of dividing the cross section of a column into strips according to the present invention.

[0016] Figure 4 It is a schematic diagram of the meshing of the NoM plane according to the present invention.

[0017] Figure 5 It is a schematic diagram of lateral deformation displacement calculation of the present invention.

[0018] Figure 6 It is a schematic diagram of calculating the ultimate bearing capacity of the present invention. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] See also Figure 1 to Figure 6 In an embodiment of the present invention, a numerical calculation method for compressive bearing and deformation of a high-strength reinforced concrete column comprises the following steps: S1, such as Figure 1 As shown in Figure 2, through numerical simulation, the strain values ​​of the high-strength steel bar eccentric column away from the axial force side and the adjacent axial force side are continuously changed; the strain of each side away from the axial force and the strain of the adjacent axial force side are as shown in Figure 2. Figure 2 As shown, a set of strain pairs is formed; S2, such as Figure 3 As shown, the cross section of the column is evenly divided into QA strip is formed, and a trapezoidal numerical integration is performed on each strain pair along the neutral axis direction of the vertical column section, so as to inversely calculate the axial force, bending moment and curvature corresponding to each strain pair; the curvature of this application should be understood as the angle between the upper and lower cross sections after deformation within the unit length of the column (along the height direction of the column) corresponding to the strain pair.

[0021] ; in, N It represents the axial force on the column section; M represents the bending moment on the column section; represents the curvature of the cylinder section; It means that under the action of strain, the j The corresponding stress of the column at the strip dividing line is: j The value range is 1, 2, 3, ..., Q -1, Q ; It means that under the action of strain, the j+1 The corresponding stress of the column at each strip dividing line; b Indicates the width of the column section; h Indicates the height of the column section; It means that under the action of strain, j The vertical distance between the center of each strip and the geometric center axis of the column section; It means that under the action of strain, the column p Axial force on the root longitudinal reinforcement; U represents the total number of longitudinal reinforcements in the column, p The value range is 1, 2, 3, ..., U－1 , U ; It means that under the action of strain, the column p The vertical distance between the root longitudinal reinforcement and the geometric center axis of the column section; represents the strain on the side of the strain pair away from the axial force; Represents the strain on the adjacent axial force side of a strain pair.

[0022] S3. Filter effective strain pairs and optimize the remaining strain pair data as a data set.

[0023] S31,N , M , As the coordinate axis, a spatial rectangular coordinate system is constructed with each strain pair corresponding to ( N , M , ) as a point in a spatial rectangular coordinate system; S32, delete the space rectangular coordinate system N or M For points in the negative state, project the remaining points to NoM On the plane, NoM The envelope of the projection points of each point in the plane is used as the cross section of the cylinder. NM curve; S33, all the above ( N , M , ) Points according to N The sizes are grouped and the ,common p groups, each of which contains indivual( N , M , ) points. For each point in each group, NM The curvature of each point on the curve is the reference curvature, when any strain is N Value and NM On the curve N The corresponding values ​​are equal or close (the absolute value of the error does not exceed 0.5 times the group interval), and the curvature of the strain pair When it is greater than the base curvature, the strain pair is deleted; S34, such as Figure 4 As shown, NoM Optimization of residual strain after plane meshing; exist NoM In the plane, M is the horizontal axis, N is the vertical axis, NoM Perform grid division to form a partitioned grid; construct a computational grid with the nodes of the partitioned grid as the center, and the size and shape of the computational grid correspond to the size and shape of the partitioned grid. Inverse calculation using plane interpolation within the computational grid : ; in, It represents the maximum axial compressive bearing capacity of the high-strength steel bar eccentric compression column; It represents the maximum bending moment of the high-strength steel bar eccentrically loaded column; Indicates the number of columns that the grid is divided into vertically; Indicates the number of rows of grid divisions along the horizontal direction; Indicates the vertical step length of a single grid; Indicates the horizontal step size of a single grid; Indicates that the grid is divided into n List m The strain at the row node is related to the curvature of the corresponding column section; express n List m The total amount of strain pairs in the computational grid corresponding to the row node; Indicates the calculation grid The curvature of the cylindrical section corresponding to each strain pair.

[0024] The calculation steps of plane interpolation are as follows: based on is the original database, Point ( N nm , M nm , ) in the axial force N nm and bending moment M nm As a benchmark, find the nearest ( N nm , M nm ) Three points that are relatively scattered P 1 ( N 1 , M 1 , )、 P 2 ( N 2 , M 2 , )as well as P 3 ( N 3 , M 3 , ), and then find the plane passing through these three points : .

[0025] in, A , B as well as C All flat The parameter to be requested is given by P1 , P2 and P3 Substitute into this plane equation to obtain, and finally N nm and M nm Substitute into the plane In the equation of .

[0026] In this step, meshing can be used to fit specific ( N , M ) combination.

[0027] Due to the discreteness of the data points, not every are all countable, not all dotted grids contain at least one ( N , M , ) points, and in terms of program running efficiency and calculation accuracy, it is not necessary to All are calculable.

[0028] S4. Calculate the ultimate bearing capacity or lateral deformation displacement of the column under different conditions based on the data set.

[0029] S41. After determining the axial force on the column, calculate the lateral deformation displacement of the column: S411, such as Figure 5 As shown, the column is divided into two equal parts along the eccentric compression height direction of the column. k segment, thus forming a k+1 Considering that the deformation of the actual column is small, the influence of the second-order differential between the lateral bending deformation of the column and the column height on the curvature of the column can be ignored. x Axis and y Axis, the lateral deformation displacement at each interface boundary is: ; in, Indicates the column +1 The lateral deformation displacement at the interface boundary; Indicates the column The lateral deformation displacement at the interface boundary; Indicates the column －1 The lateral deformation displacement at the interface boundary; a The value range is 1, 2, 3, ..., k , k+1 ; Represents the spacing between adjacent interfaces; Indicates the subject The curvature of the interface is calculated according to step S34; S412, because the two ends of the column are hinged during the bias test, the natural as well as 。 can be used as a starting point for initial calculations, and It can be used as a criterion for determining whether the calculated column deformation curve under the action of the axial force is a true value. The second interface is taken as the starting interface, and a value close to 0 (preferably 1×10 -6 ) of the lateral deformation displacement value ; S413, based on the axial force on the column, the initial eccentricity of the column and the assumed lateral displacement value of the second interface Calculate the current bending moment at the second interface ; S414: According to step S411, Calculate the lateral deformation displacement value of the third interface of the column ; S415. Calculate the lateral deformation displacement values ​​of all interfaces of the column in sequence and record the k+1 The lateral deformation displacement value of the interface ; S416, gradually expand the step S412 , repeat steps S413 to S415 until the calculated and the value obtained in step S415 When the sign is opposite, the output ; S417: According to the output in step S416 , the true lateral displacement value of the second interface is gradually obtained by the dichotomy method (the allowable error given in this application is 0.01 mm), thereby obtaining the lateral deformation displacement curve of the column under the action of a certain axial force.

[0030] The solution steps of the binary method are as follows: After obtaining the interval where the true lateral displacement of the second interface is located ( , ), first take the assumed lateral displacement value of the second interface as: , and then calculate when the lateral displacement of the second interface is When , and then check the calculated Whether the absolute value is less than the given allowable error, if it meets the above error, the calculation ends; otherwise, judge in turn and and The positive and negative sign of , then the trial calculation interval of the second interface true lateral displacement is taken as ( , ), and make this new interval replace the original interval ( , ), and then take the new assumed lateral displacement value of the second interface as: , continue to calculate the lateral displacement of the top interface of the column. If it meets the given error, the calculation ends, otherwise repeat step S417. , then the trial calculation interval of the second interface true lateral displacement is taken as ( , ), and make this new round of intervals replace the original intervals ( , ), and then take the new assumed lateral displacement value of the second interface as: , continue to calculate the lateral displacement of the top interface of the column. If it meets the given error, the calculation ends, otherwise repeat step S417.

[0031] S42, such as Figure 6 As shown, calculate the ultimate bearing capacity of the column under eccentric compression state; Before the calculation begins, the column cross section NM The curve is processed equivalently to obtain the cylinder curve, is the cross section of the cylinder under axial force The maximum lateral displacement deformation value allowed under the action; ; in, It represents the axial force to which the column section is subjected when it reaches its ultimate bearing capacity; It represents the bending moment to which the column section is subjected when it reaches its ultimate bearing capacity; Represents the initial eccentricity of the cylinder.

[0032] S421, given initial axial pressure of the cylinder along the axial direction N 0 as well as N1 , N 0 < N 1 , in this application N 0 =100kN, N 1 = 200 kN. According to step S41, calculate N 0 as well as N 1 The lateral displacement deformation value of the column corresponding to the axial force d 0 as well as d 1 ; S422, connection ( d 0 , N 0 )and( d 1 , N 1 ) forms a straight line with Nf The curves intersect at ( d 2 , ); S423, calculate the lateral displacement deformation value of the column in the column d 2 The corresponding axial force N 2 ; In this step, N 1 Based on the axial force, select the current axial force increment step for: . Calculate the lower axial force: The corresponding lateral displacement deformation value of the column , i The value is .

[0033] like Less than d 2 , then keep the current axial force increment step unchanged, that is, , continue to increase the magnitude of the axial force.

[0034] like Greater than d 2 , then further reduce the current axial force increment step size and take it as: .

[0035] Repeat the above steps until and d 2 The relative error is less than 0.01 or Less than 0.001kN, take N2 = ; S424、( d 0 , N 0 )and( d 1 , N 1 ) are replaced by ( d 1 , N 1 )and( d 2 , N 2 ), repeat steps S422 to S423, and calculate ( d 3 , N 3 )and( d 3 , ), d 4 , N 4 )and( d 4 , ),…,( d i , N i )and( d i , ); S425, comparison and judgment and The value of and When the absolute difference is less than the set value, the output is the ultimate bearing capacity of the column.

[0036] In order to verify the accuracy of the numerical calculation of this application, high-strength reinforced concrete eccentric compression columns and high-strength reinforced concrete axial compression columns were prepared and tested. The measured yield strength of the high-strength steel bars in the column exceeded 650Mpa, and the reinforcement of the column is shown in Table 1 below.

[0037] Table 1 ;

[0038] In the table, Group 1 and Group 2 are high-strength reinforced concrete eccentrically compressed columns. The length of all columns is 1250mm. The 6 longitudinal bars are evenly and symmetrically arranged along the tension and compression sides of the columns. The stirrups are arranged in the same way and are all double-legged stirrups. The column protective layer is 20mm.

[0039] Group 3 consists of high-strength reinforced concrete axial compression columns. All specimens are 650mm long, with four longitudinal bars arranged evenly and symmetrically. The stirrups are of the same type and are all double-legged stirrups. The column protection layer is 20mm.

[0040] The initial eccentricity moments of the three specimens in group 1, N1-80-40, N2-80-80 and N3-80-120, were calculated according to the calculation method of this application. e =40mm gradually increases to e =80mm and e =120mm, the ultimate bearing capacity calculated by this calculation method drops from 1706.22kN to 991.48kN and 574.11kN, while the measured values ​​in the test are 1692.67kN, 1000.05kN and 576.45kN, with relative errors of +0.80%, -0.86% and -0.45%, respectively; the corresponding lateral displacement deformation value in the calculated column increases from 4.8mm to 6.3mm and 6.9mm, while the measured values ​​in the test are 5.2mm, 6.6mm and 7.2mm, respectively, with relative errors of -7.69%, -4.55% and -4.17%, respectively.

[0041] Similarly, for the three specimens N4-50-40, N5-60-40 and N1-80-40 in group 2, the concrete cube compressive strength is given by f cu =50MPa and then increase to f cu =60MPa and f cu =80MPa, the ultimate bearing capacity calculated by this calculation method increases from 1402.95kN to 1541.11kN and 1706.22kN. Compared with the experimental values ​​of 1397.59kN, 1530.87kN and 1692.67kN, the relative errors are +0.49%, +0.69% and +0.80% respectively.

[0042] Similarly, for the two axial compression specimens N6-80-0 and N7-80-0 in group 3, the ultimate bearing capacities calculated by this calculation method are 1952.8 kN and 1803.1 kN respectively. Compared with the corresponding experimental values ​​of 1955.2 kN and 1788.0 kN, the relative errors are -0.12% and +0.84% ​​respectively.

[0043] In summary, the ultimate bearing capacity and corresponding displacement of the column calculated by this numerical calculation method are in good agreement with the experimental results, which shows the accuracy and correctness of this calculation method. The calculation data of each specimen are shown in Table 2 below.

[0044] Table 2 ;

[0045] The specification in Table 2 refers to GB50010-2010 (2015 edition). In the calculation process, the strength of materials such as concrete and high-strength steel bars adopts the laboratory measured strength; in the calculation process using the standard formula, the value of e takes into account the lateral deflection occurring in the column when the column reaches the ultimate bearing capacity during the experiment, and does not consider the influence of the additional eccentricity of this specification; other parameters required in the calculation process according to the specification are selected in accordance with this specification.

[0046] The numerical calculation method of this application is based on the assumption of a plane section, and only performs strip division in the longitudinal direction of the column and in the direction perpendicular to the neutral axis of the column cross section. Therefore, it has a faster calculation speed and higher calculation efficiency than the traditional ABAQUS software simulation. The calculation time of the same component in the ABAQUS general finite element software and the calculation method of this application is shown in Table 3 below.

[0047] Table 3 ;

[0048] From the above, we can see that the calculation time of this application is about 5.4% of the calculation time of ABAQUS software, which greatly improves the calculation efficiency.

[0049] The basic principles of the present application are described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, effects, etc. mentioned in the present application are only examples and not limitations, and it cannot be considered that these advantages, strengths, effects, etc. are required by each embodiment of the present application. In addition, the specific details disclosed above are only for the purpose of illustration and ease of understanding, not for limitation, and the above details do not limit the present application to being implemented by adopting the above specific details.

Claims

1. A numerical calculation method for compressive bearing and deformation of high-strength reinforced concrete columns, characterized in that: The steps include: S1, continuously changing the strain values ​​of the high-strength steel bar eccentric column away from the axial force side and the adjacent axial force side, each strain away from the axial force side and the strain adjacent to the axial force side constitute a set of strain pairs; S2. Inversely calculate the axial force, bending moment and curvature of the column section under the corresponding state according to the strain; S3, screening effective strain pairs, and optimizing the remaining strain pair data as a data set; S4. Calculate the ultimate bearing capacity or lateral deformation displacement of the column under different conditions based on the data set.

2. A numerical calculation method for compressive bearing and deformation of high-strength reinforced concrete columns according to claim 1, characterized in that: In step S2, the cross section of the cylinder is evenly divided into Q After each strip, the strain pairs are numerically integrated to calculate the axial force, bending moment and curvature of the cylinder section in the state corresponding to each strain pair. ； in, N It represents the axial force on the column section; M represents the bending moment on the column section; represents the curvature of the cylinder section; It means that under the action of strain, the j The corresponding stress of the column at the strip dividing line is: j The value range is 1, 2, 3, ..., Q -1, Q ; It means that under the action of strain, the j+1 The corresponding stress of the column at each strip dividing line; b Indicates the width of the column section; h Indicates the height of the column section; It means that under the action of strain, j The vertical distance between the center of each strip and the geometric center axis of the column section; It means that under the action of strain, the column p Axial force on the root longitudinal reinforcement; U represents the total number of longitudinal reinforcements in the column, p The value range is 1, 2, 3, ..., U－1 , U ; It means that under the action of strain, the column p The vertical distance between the root longitudinal reinforcement and the geometric center axis of the column section; represents the strain on the side of the strain pair away from the axial force; Represents the strain on the adjacent axial force side of a strain pair.

3. The numerical calculation method for compressive bearing and deformation of a high-strength reinforced concrete column according to claim 2 is characterized in that: In step S3: S31, N, M, As the coordinate axis, a spatial rectangular coordinate system is constructed with each strain pair corresponding to ( N , M , ) as a point in a spatial rectangular coordinate system; S32, delete the space rectangular coordinate system N or M For points in the negative state, project the remaining points to NoM On the plane, NoM The envelope of the projection points of each point in the plane is used as the cross section of the cylinder. NM curve; S33, NM The curvature of each point on the curve is the reference curvature, when any strain is N Value and NM On the curve N The values ​​are equal, and the curvature of the strain pair When it is greater than the base curvature, the strain pair is deleted; S34, will NoM The residual strain is optimized after plane meshing.

4. A numerical calculation method for compressive bearing and deformation of high-strength reinforced concrete columns according to claim 3, characterized in that: In step S34, NoM In the plane, M is the horizontal axis, N is the vertical axis, NoM Performing grid division to form a division grid; The computational grid is constructed with the nodes of the grid as the center. The size and shape of the computational grid correspond to the size and shape of the grid. Inverse calculation using plane interpolation within the computational grid : ； in, It represents the maximum axial compressive bearing capacity of the high-strength steel bar eccentric compression column; It represents the maximum bending moment of the high-strength steel bar eccentrically loaded column; Indicates the number of columns that the grid is divided into vertically; Indicates the number of rows of grid divisions along the horizontal direction; Indicates the vertical step length of a single grid; Indicates the horizontal step size of a single grid; Indicates that the grid is divided into n List m The strain at the row node is related to the curvature of the corresponding column section; express n List m The total amount of strain pairs in the computational grid corresponding to the row node; Indicates the number of The curvature of the cylindrical section corresponding to each strain pair.

5. A numerical calculation method for compressive bearing and deformation of high-strength reinforced concrete columns according to any one of claims 2 to 4, characterized in that: S41. After determining the axial force on the column, calculate the lateral deformation displacement of the column: S411, along the height direction of the column, divide the column into k segment, thus forming a k+1 The lateral deformation displacement at the interface boundary is: ； in, Indicates the column +1 The lateral deformation displacement at the interface boundary; Indicates the column The lateral deformation displacement at the interface boundary; Indicates the column －1 The lateral deformation displacement at the interface boundary; The value range is 1, 2, 3, ..., k , k+1 ; Indicates the spacing between adjacent interfaces; Indicates the subject The curvature of the interface is calculated according to step S34; S412, the first interface of the cylinder and the k+1 The lateral deformation displacement value of the first interface is 0, the second interface is taken as the starting interface, and a lateral deformation displacement value is assigned to the second interface. , The value assigned to -6 ; S413, based on the axial force on the column, the initial eccentricity of the column and the assumed lateral displacement value of the second interface Calculate the current bending moment at the second interface ; S414: Calculate the lateral deformation displacement value of the third interface of the column according to step S411 ; S415. Calculate the lateral deformation displacement values ​​of all interfaces of the column in sequence and record the k+1 The lateral deformation displacement value of the interface ; S416, gradually expand the , repeat steps S413 to S415 until the calculated and the value obtained in step S415 When the sign is opposite, the output ; S417: According to the output in step S416 , the true lateral displacement value of the second interface is gradually obtained through the dichotomy method, thus obtaining the lateral deformation displacement curve of the column under the action of a certain axial force.

6. A numerical calculation method for compressive bearing and deformation of high-strength reinforced concrete columns according to claim 5, characterized in that: When calculating the maximum lateral displacement of a column, the cross section of the column is NM The curve is processed equivalently to obtain the cylinder curve, is the cross section of the cylinder under axial force The maximum lateral displacement deformation value allowed under the action; ； in, It represents the axial force to which the column section is subjected when it reaches its ultimate bearing capacity; It represents the bending moment to which the column section is subjected when it reaches its ultimate bearing capacity; Represents the initial eccentricity of the cylinder.

7. A numerical calculation method for compressive bearing and deformation of high-strength reinforced concrete columns according to claim 6, characterized in that: S42. Calculate the ultimate bearing capacity of the column under eccentric compression: S421, given initial axial pressure of the cylinder along the axial direction N 0 as well as N 1 , N 0 < N 1 , calculated according to step S41 N 0 as well as N 1 The lateral displacement deformation value of the column under the axial pressure d 0 as well as d 1 ; S422, connection ( d 0 , N 0 )and( d 1 , N 1 ) forms a straight line with Nf The curves intersect at ( d 2 , ); S423, calculate the lateral displacement deformation value of the column in the column d 2 The corresponding axial force N 2 ; S424、( d 0 , N 0 )and( d 1 , N 1 ) are replaced by ( d 1 , N 1 )and( d 2 , N 2 ), repeat steps S422 to S423, and calculate ( d 3 , N 3 )and( d 3 , ), d 4 , N 4 )and( d 4 , ),…,( d i , N i )and( d i , ); S425, comparison and judgment and The value of and When the absolute difference is less than the set value, the output is the ultimate bearing capacity of the column.

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