An intelligent calculation method for time-varying deformation of RC components considering corridor stiffness

Abstract

The present invention discloses an intelligent calculation method for the time-varying deformation of RC components taking into account the stiffness of the corridor, and belongs to the technical field of time-varying deformation of concrete components. The method includes constructing an axial time-varying deformation model of reinforced concrete components; obtaining the reinforcement ratio of reinforced concrete components, the elastic modulus of steel bars, and the elastic modulus of concrete, and calculating stiffness information; calculating the stiffness of the corridor; constructing a group of fractional-order calculus constitutive equations; performing Laplace transformation on the group of constitutive equations, and then performing MATLAB calculations to obtain the creep flexibility expression of the axial time-varying deformation model of reinforced concrete components; and calculating the total strain of the vertical components based on the creep flexibility expression. The present invention combines the basic theory of fractional-order calculus and the time-varying characteristics of reinforced concrete, effectively utilizing the advantage that the mechanical model fitting effect of the fractional-order calculus unit is significantly better than that of the traditional mechanical unit model, and fully considering the time-varying deformation of reinforced concrete components in actual engineering.

Description

Technical Field

[0001] The present invention belongs to the technical field of time-varying deformation of concrete components, and particularly relates to an intelligent calculation method for time-varying deformation of RC components taking into account corridor stiffness. Background Art

[0002] Concrete is generally considered a solid material. However, when subjected to stress or changes in the external environment, its deformation is often time-dependent. The American Concrete Institute (ACI 209R) and the European Model Code (MC2010) have each proposed concrete creep models based on the research of numerous scholars. However, because these models are derived from regression analysis of standard laboratory creep test results, and because the dimensions of the test components differ significantly from those of actual concrete components in engineering projects, the predicted results often differ significantly from the measured strains, making them inadequate for direct guidance in construction and design.

[0003] Common calculation models and specifications for the time-varying characteristics and shrinkage and creep of concrete include the MC 2010 model, ACI209R92 model, B3 model, and GL2000 model. The components of the above models are standard-sized plain concrete test blocks. However, in actual engineering, concrete is often used together with steel bars. The forces on concrete and steel bars are coupled, and the horizontal connecting members between reinforced concrete components also have a certain influence on their deformation.

[0004] Therefore, it is necessary to establish the corresponding axial time-varying model for reinforced concrete components and consider the corridor stiffness to calculate the time-varying development of the axial compression of vertical components. Summary of the Invention

[0005] The purpose of the embodiments of the present invention is to provide an intelligent calculation method for the time-varying deformation of RC components that takes into account the stiffness of corridors. This method combines the basic theory of fractional calculus with the time-varying characteristics of reinforced concrete. It effectively utilizes the advantage of the mechanical model fitting effect of fractional calculus units, which is significantly better than that of traditional mechanical unit models. It also fully considers the time-varying deformation of reinforced concrete components in actual engineering projects, thereby resolving at least one technical problem involved in the background technology.

[0006] In order to solve the above-mentioned technical problems, the present invention is achieved as follows:

[0007] The present invention provides an intelligent calculation method for time-varying deformation of RC components taking into account corridor stiffness, comprising the following steps:

[0008] Step S1, constructing a time-varying axial deformation model of reinforced concrete components based on fractional derivatives;

[0009] Step S2, obtaining the reinforcement ratio of the reinforced concrete component, the elastic modulus of the steel bar, and the elastic modulus of the concrete based on the cross-sectional information of different vertical components, and calculating the stiffness information in the axial time-varying deformation model of the reinforced concrete component;

[0010] Step S3, calculating the corridor stiffness based on the corridor component information between the vertical components;

[0011] Step S4, constructing a fractional-order calculus constitutive equation group for the time-varying development process of axial compression of adjacent vertical components with corridor components;

[0012] Step S5, performing Laplace transform on the constitutive equations, and then performing MATLAB calculation to obtain the creep flexibility expression of the axial time-varying deformation model of the reinforced concrete component;

[0013] Step S6: Calculate the total strain of the vertical component according to the creep flexibility expression.

[0014] Optionally, in step S1, the axial time-varying deformation model of reinforced concrete components based on fractional derivatives adopts an improved fractional-order Zener model, which is composed of an improved fractional-order calculus Zener model connected in series with a concrete shrinkage unit to form a vertical component model. Two identical vertical components are arranged side by side, and the two adjacent vertical components are connected by a corridor component composed of a shear spring to achieve coupled deformation.

[0015] Optionally, the improved fractional calculus Zener model includes a concrete elastic unit, a concrete creep unit and an elastic unit of a steel bar or steel section, wherein the concrete elastic unit and the concrete creep unit are first connected in series, and then the series-connected concrete elastic unit and concrete creep unit are connected in parallel with the elastic unit of the steel bar or steel section.

[0016] Optionally, in step S2, the stiffness information includes the stiffness parameter k provided by the concrete β and the stiffness parameter provided by the steel bar, k γ , which is expressed by the following formula:

[0017] k β =E c (1-ρ s ) (1)

[0018] k γ =E s ρ s (2)

[0019] Where, ρ s is the reinforcement ratio of reinforced concrete components; E s is the elastic modulus of the steel bar; E c is the elastic modulus of concrete.

[0020] Optionally, in step S3, the corridor stiffness k L It is expressed by the following formula:

[0021] k L =12EI / l 3 (3)

[0022] Where l represents the span of the corridor component; E represents the elastic modulus of the corridor component; and I represents the moment of inertia of the corridor component.

[0023] Optionally, in step S4, the constitutive equations include:

[0024]

[0025] Where, σ1(t) and σ2(t) represent the total stress of vertical components 1 and 2 that changes with time, respectively. The specific values are determined according to the stress sensor measurement or the design purpose; ε1(t) and ε2(t) represent the total strain of vertical components 1 and 2 that changes with time, respectively. C α1 、C α2 , α1, α2 are coefficients, and α∈(0,1); is the α-order inverse of stress with respect to time; is the α-order inverse of strain with respect to time; H represents the height of vertical members 1 and 2; A1 and A2 represent the cross-sectional areas of vertical members 1 and 2, respectively; k β1 、k β2 are the stiffness parameters provided by the concrete in vertical members 1 and 2 respectively; k γ1 、k γ2 are the stiffness parameters provided by the steel bars in vertical members 1 and 2 respectively; △ε(t) is the axial strain difference between vertical members 1 and 2, △ε(t) = ε1(t) - ε2(t).

[0026] Optionally, step S5 specifically includes:

[0027] Performing Laplace transform on formula (4) and formula (5) and eliminating the differential operators, we can obtain:

[0028]

[0029] Where l1 and l2 represent the upper axial stress of the two vertical components 1 and 2 respectively; s represents the coefficient in Laplace space converted from time t by Laplace transform; creep flexibility is is an unknown variable;

[0030] Calculate the formula (6) and formula (7) using MATLAB to get the creep flexibility The specific expression of .

[0031] Optionally, step S6 specifically includes:

[0032] In step S61, the Talbot method, a high-precision numerical integration method, is used to perform Laplace inverse transformation to obtain the creep flexibility J1(t) and J2(t) of the two vertical components 1 and 2 in the time domain space respectively:

[0033]

[0034] Where, represents the Laplace transform operator;

[0035] Step S62: The total strains ε1(t) and ε2(t) of the vertical members 1 and 2 are calculated by the upper axial forces of the vertical members 1 and 2 and the shrinkage deformation of the members:

[0036] ε1(t)=σ1(t)J1(t)+ε sh1 (t) (10)

[0037] ε2(t)=σ2(t)J2(t)+ε sh2 (t) (11)

[0038] Where, ε sh1 (t), ε sh2 (t) represents the shrinkage deformation of the component, which is calculated through test results or standard formulas.

[0039] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the steps of the above method when executing the computer program.

[0040] The present invention also provides a computer-readable storage medium storing a computer program, wherein the computer program implements the steps of the above method when executed by a processor.

[0041] The present invention provides a computer program product, comprising a computer program, which implements the steps of the above method when executed by a processor.

[0042] The beneficial effects of the embodiments of the present invention are:

[0043] 1. The present invention fully considers the relationship between the axial deformation of the vertical member and the horizontal connecting member, and can take into account the shear stiffness provided by the horizontal connecting member when calculating the axial deformation.

[0044] 2. The present invention makes full use of fractional derivatives instead of traditional multi-parameter calculation formulas to describe the time-varying deformation characteristics of components, which greatly reduces the calculation parameters while giving the components more reasonable and intuitive physical properties. At the same time, a calculation method for corresponding parameters is proposed based on the cross-sectional characteristics of the components, which improves the efficiency of the time-varying deformation calculation of the components while also making it more reasonable and interpretable.

[0045] 3. The present invention uses the Laplace transform and numerical inverse Laplace transform methods to directly solve the constitutive equation. This method is universal and can be applied to various other types of constitutive relations proposed, and the calculation process is clear.

[0046] 4. The axial time-varying deformation model of reinforced concrete components based on fractional-order derivatives of the present invention adopts an improved fractional-order Zener model, connecting two adjacent vertical components through a corridor component composed of a shear spring to achieve coupled deformation, thereby being able to reasonably calculate the time-varying deformation of the mutual coupling between structural components. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive work, among which:

[0048] Figure 1 Schematic diagram of the axial deformation model of adjacent vertical components considering the stiffness of the corridor provided by the present invention;

[0049] Figure 2 This is a flow chart of the calculation of the axial deformation model of adjacent vertical components considering the stiffness of the corridor provided by the present invention;

[0050] Figure 3 (a) to 3(f) are the axial deformation models of adjacent vertical components considering the stiffness of the corridor provided by the present invention, and the influence of the stiffness of the connecting beam on the compression deformation of the components under different parameters;

[0051] Figure 4 This is one of the hardware structure diagrams of the electronic device provided by the present invention;

[0052] Figure 5 This is the second schematic diagram of the hardware structure of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0053] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0054] The terms "first," "second," and the like in the specification and claims of the present invention are used to distinguish similar objects, and are not used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of the present invention can be implemented in an order other than that illustrated or described herein, and that the objects distinguished by "first," "second," and the like are generally of the same type, and do not limit the number of objects. For example, the first object can be one or more. In addition, the term "and / or" in the specification and claims refers to at least one of the connected objects, and the character " / " generally indicates that the objects connected are in an "or" relationship.

[0055] An embodiment of the present invention provides an intelligent calculation method for time-varying deformation of RC components taking into account corridor stiffness, comprising the following steps:

[0056] Step S1, constructing a time-varying axial deformation model of reinforced concrete components based on fractional derivatives;

[0057] Step S2, obtaining the reinforcement ratio of the reinforced concrete component, the elastic modulus of the steel bar, and the elastic modulus of the concrete based on the cross-sectional information of different vertical components, and calculating the stiffness information in the axial time-varying deformation model of the reinforced concrete component;

[0058] Step S3, calculating the corridor stiffness based on the corridor component information between the vertical components;

[0059] Step S4, constructing a fractional-order calculus constitutive equation group for the time-varying development process of axial compression of adjacent vertical components with corridor components;

[0060] Step S5, performing Laplace transform on the constitutive equations, and then performing MATLAB calculation to obtain the creep flexibility expression of the axial time-varying deformation model of the reinforced concrete component;

[0061] Step S6: Calculate the total strain of the vertical component according to the creep flexibility expression.

[0062] In step S1, see Figure 1As shown in the figure, the axial time-varying deformation model of reinforced concrete components based on fractional derivatives adopts an improved fractional Zener model, which consists of an improved fractional calculus Zener model connected in series with a concrete shrinkage unit to form a vertical component model. Two identical vertical components are arranged side by side, and the two adjacent vertical components are connected by a corridor component composed of a shear spring to achieve coupled deformation.

[0063] The improved fractional calculus Zener model includes a concrete elastic unit, a concrete creep unit, and an elastic unit of a steel bar or a steel section, wherein the concrete elastic unit and the concrete creep unit are first connected in series, and then the series-connected concrete elastic unit and the concrete creep unit are connected in parallel with the elastic unit of the steel bar or the steel section.

[0064] In step S2, the stiffness information includes the stiffness parameter k provided by the concrete β and the stiffness parameter provided by the steel bar, k γ , which is expressed by the following formula:

[0065] k β =E c (1-ρ s ) (1)

[0066] k γ =E s ρ s (2)

[0067] Where, ρ s is the reinforcement ratio of reinforced concrete components; E s is the elastic modulus of the steel bar; E c is the elastic modulus of concrete;

[0068] In step S3, the corridor stiffness k L It is expressed by the following formula:

[0069] k L =12EI / l 3 (3)

[0070] Where l represents the span of the corridor component; E represents the elastic modulus of the corridor component; and I represents the moment of inertia of the corridor component.

[0071] In step S4, in building structures, vertical components are usually connected by coupling beams. A column-beam-wall substructure is often coupled to some extent. Existing concrete creep formulas are all derived from experimental results of single concrete components under axial load. Therefore, by simplifying the load process of a group of adjacent vertical components and their coupling beams, the proposed constitutive model can be used to establish a set of fractional calculus constitutive equations for the axial compression creep development process of adjacent vertical components that considers the stiffness of the corridor.

[0072] The spans between adjacent vertical members may be small (especially when the spacing between shear walls is small), and the cross-section of the coupling beam is large. Therefore, the influence of the coupling beam can no longer be ignored. Based on the fractional calculus constitutive model, a group of adjacent vertical members are connected by a spring in the vertical direction. The spring stiffness is the shear stiffness of the coupling beam, which can be obtained by simple structural mechanics or finite element calculations, such as Figure 1 shown.

[0073] For the sake of simplicity, the influence of shrinkage is not considered for the time being. The constitutive models of the left and right vertical members are the same. When the coupling beam is considered, it is assumed that the axial compression deformation of the right vertical member is greater than that of the left. The respective constitutive equations are:

[0074]

[0075] Where, σ1(t) and σ2(t) represent the total stress of vertical components 1 and 2 respectively, which can be measured by stress sensors or determined according to the design purpose; ε1(t) and ε2(t) represent the total strain of vertical components 1 and 2 respectively. α1 、C α2 , α1, α2 are coefficients, and α∈(0,1); is the α-order inverse of stress with respect to time; is the α-order inverse of strain with respect to time; H represents the height of vertical members 1 and 2; A1 and A2 represent the cross-sectional areas of vertical members 1 and 2, respectively; k β1 、k β2 are the stiffness parameters provided by the concrete in vertical members 1 and 2 respectively; k γ1 、k γ2 are the stiffness parameters provided by the steel bars in vertical members 1 and 2 respectively; △ε(t) is the axial strain difference between vertical members 1 and 2, △ε(t) = ε1(t) - ε2(r).

[0076] The calculation flow chart is as follows Figure 2 As shown in the figure, in order to quantitatively analyze the influence of the coupling beam on the adjacent vertical components, the results of changing individual influencing parameters are calculated by formula (4) and (5) to perform parameter analysis. The specific parameter values are shown in Table 1, and the corresponding results are shown in Figure 3 As shown in the figure, the dotted and solid lines represent the results without and with the influence of the coupling beam. It is not difficult to find that when the span of the two vertical members is 5m, the stiffness provided by the coupling beam is small, so the creep development process of each member is less affected by the coupling beam. There is no obvious difference whether the coupling beam is considered or not. As the span gradually decreases ( Figure 3(a)-(c)), the stiffness provided by the coupling beam gradually increases, and the creep development of the vertical component is affected by the creep of the other side component, making the creep development of the two components tend to be the same. When the cross-sectional areas of the two components are the same, the creep of the vertical component tends to approach the creep of the other component equally, while when the cross-sectional areas of the components are different ( Figure 3 (d)-(f)), it is obvious that the component with smaller cross-sectional area has a greater tendency to move closer to the other component.

[0077] Table 1 Calculation parameter values

[0078]

[0079] Step S5 specifically includes:

[0080] Performing Laplace transform on formula (4) and formula (5) and eliminating the differential operators, we can obtain:

[0081]

[0082] Where l1 and l2 represent the upper axial stress of the two vertical components 1 and 2 respectively; s represents the coefficient in Laplace space converted from time t by Laplace transform; creep flexibility is is an unknown variable;

[0083] Calculate the formula (6) and formula (7) using MATLAB to get the creep flexibility The specific expression of .

[0084] Step S6 specifically includes:

[0085] In step S61, the Talbot method, a high-precision numerical integration method, is used to perform Laplace inverse transformation to obtain the creep flexibility J1(t) and J2(t) of the two vertical components 1 and 2 in the time domain space respectively:

[0086]

[0087] Where, represents the Laplace transform operator;

[0088] Step S62: The total strains ε1(t) and ε2(t) of the vertical members 1 and 2 are calculated by the upper axial forces of the vertical members 1 and 2 and the shrinkage deformation of the members:

[0089] ε1(t)=σ1(t)J1(t)+ε sh1 (t) (10)

[0090] ε2(t)=σ2(t)J2(t)+ε sh2 (t) (11)

[0091] Where, ε sh1 (t), ε sh2 (t) represents the shrinkage deformation of the component, which is calculated based on test results or standard formulas, such as the calculation formula in ACI209R-92:

[0092]

[0093] where ε shu =780γ sh , γ sh =γ sh,ts γ sh,RH γ sh,vs γ sh,s γ sh,ψ γ sh,c γ sh,α , adjustment coefficient γ for curing specimen sh,ts =1.202-0.2337log(t s );γ sh,RH is the ambient humidity adjustment coefficient. When the ambient humidity is between 0.4 and 0.8, γ sh,RH =1.4-1.02RH, between 0.8~1, γ sh,RH =3-3RH; Compared with creep, shrinkage has an additional cement content adjustment factor γ sh,c =0.75+0.00061c, where c is the cement content; f c is the concrete strength; t c The time point when the component begins to be exposed to the air.

[0094] like Figure 4 As shown, an embodiment of the present invention further provides an electronic device 600, which includes a processor 601, a memory 602, and a program or instruction stored in the memory 602 and executable on the processor 601. When the program or instruction is executed by the processor 601, each process of the embodiment of the intelligent calculation method for time-varying deformation of RC components considering corridor stiffness is implemented, and the same technical effect can be achieved. To avoid repetition, it will not be described here.

[0095] It should be noted that the first electronic device in the embodiment of the present invention includes the mobile electronic device and the non-mobile electronic device mentioned above.

[0096] Figure 5 The present invention is a hardware structure diagram of an electronic device.

[0097] The electronic device 700 includes but is not limited to components such as a radio frequency unit 701 , a network module 702 , an audio output unit 703 , an input unit 704 , a sensor 705 , a display unit 706 , a user input unit 707 , an interface unit 708 , a memory 709 , and a processor 710 .

[0098] Those skilled in the art will understand that the electronic device 700 may also include a power source (such as a battery) to power each component, and the power source may be logically connected to the processor 710 through a power management system, thereby implementing functions such as charging, discharging, and power consumption management through the power management system. Figure 5 The electronic device structure shown in the figure does not constitute a limitation on the electronic device. The electronic device may include more or fewer components than shown in the figure, or combine certain components, or arrange the components differently, which will not be repeated here.

[0099] It should be understood that in embodiments of the present invention, the input unit 704 may include a graphics processing unit (GPU) 7041 and a microphone 7042. The graphics processor 7041 processes image data of still images or videos obtained by an image capture device (such as a camera) in video capture mode or image capture mode. The display unit 706 may include a display panel 7061, which may be configured in the form of a liquid crystal display, an organic light-emitting diode, or the like. The user input unit 707 includes a touch panel 7071 and other input devices 7072. The touch panel 7071 is also called a touch screen. The touch panel 7071 may include two parts: a touch detection device and a touch controller. Other input devices 7072 may include, but are not limited to, a physical keyboard, function keys (such as volume control keys, power keys, etc.), a trackball, a mouse, and a joystick, which will not be described in detail here. The memory 709 may be used to store software programs and various data, including, but not limited to, applications and operating systems. The processor 710 may integrate an application processor and a modem processor, wherein the application processor mainly processes the operating system, user interface, and applications, and the modem processor mainly processes wireless communications. It is understandable that the above-mentioned modem processor may not be integrated into the processor 710.

[0100] An embodiment of the present invention further provides a readable storage medium having a program or instruction stored thereon. When the program or instruction is executed by a processor, the various processes of the embodiment of the intelligent calculation method for time-varying deformation of RC components considering corridor stiffness are implemented, and the same technical effects can be achieved. To avoid repetition, they are not described here.

[0101] The processor is the processor in the electronic device described in the above embodiment. The readable storage medium includes a computer-readable storage medium, such as a computer read-only memory (ROM), random access memory (RAM), a magnetic disk, or an optical disk.

[0102] An embodiment of the present invention further provides a chip comprising a processor and a communication interface, wherein the communication interface is coupled to the processor, and the processor is configured to execute a program or instruction to implement the various processes of the embodiment of the intelligent calculation method for time-varying deformation of RC components taking into account corridor stiffness, and to achieve the same technical effects. To avoid repetition, these processes are not described herein.

[0103] It should be understood that the chip mentioned in the embodiment of the present invention can also be called a system-on-chip, a system-on-chip, a chip system, or a system-on-chip chip, etc.

[0104] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0105] Furthermore, it should be noted that the scope of the methods and systems of the present invention is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in reverse order, depending on the functions involved. For example, the methods described may be performed in an order different from that described, and various steps may be added, omitted, or combined. Furthermore, features described with reference to certain examples may be combined in other examples.

[0106] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the present invention and the claims, all of which are protected by the present invention.

Claims

1. An intelligent calculation method for time-varying deformation of RC components considering corridor stiffness, characterized by: The following steps are involved: Step S1: constructing an axial time-varying deformation model of reinforced concrete components based on fractional derivatives, which consists of an improved fractional-order calculus Zener model connected in series with a concrete shrinkage unit to form a vertical component model, two identical vertical components are arranged side by side, and the two adjacent vertical components are connected by a corridor component composed of a shear spring to achieve coupled deformation; the improved fractional-order calculus Zener model includes a concrete elastic unit, a concrete creep unit, and an elastic unit of a steel bar or a steel section, wherein the concrete elastic unit and the concrete creep unit are first connected in series, and then the series-connected concrete elastic unit and the concrete creep unit are connected in parallel with the elastic unit of the steel bar or the steel section; Step S2, obtaining the reinforcement ratio of the reinforced concrete component, the elastic modulus of the steel bar, and the elastic modulus of the concrete based on the cross-sectional information of different vertical components, and calculating the stiffness information in the axial time-varying deformation model of the reinforced concrete component; Step S3, calculate the corridor stiffness based on the corridor component information between the vertical components. It is expressed by the following formula: （3） Where, Indicates the span of the corridor components; represents the elastic modulus of the corridor components; represents the moment of inertia of the corridor components; Step S4: construct a fractional-order calculus constitutive equation system for the time-varying development process of axial compression of adjacent vertical components with corridor components. The constitutive equation system includes: （4） （5） Where, 、 Respectively represent the total stress of vertical components 1 and 2 changing with time, which can be measured by stress sensors or determined according to design purposes; , denote the total strains of vertical members 1 and 2 over time; 、 is the coefficient, and ; is the stress with respect to time Reciprocal of order; For the adaptation of time Reciprocal of order; H represents the height of vertical members 1 and 2; A1 and A2 represent the cross-sectional areas of vertical members 1 and 2 respectively; 、 are the stiffness parameters provided by the concrete in vertical members 1 and 2 respectively; 、 are the stiffness parameters provided by the steel bars in vertical members 1 and 2 respectively; is the axial strain difference between vertical members 1 and 2 ; Step S5, performing Laplace transform on the constitutive equations, and then performing MATLAB calculation to obtain the creep flexibility expression of the axial time-varying deformation model of the reinforced concrete component; Step S6: Calculate the total strain of the vertical component according to the creep flexibility expression.

2. The method according to claim 1, characterized in that In step S2, the stiffness information includes the stiffness parameters provided by the concrete and the stiffness parameters provided by the steel bars , which is expressed by the following formula: （1） （2） Where, is the reinforcement ratio of reinforced concrete components; is the elastic modulus of the steel bar; is the elastic modulus of concrete.

3. The method according to claim 2, characterized in that Step S5 specifically includes: Performing Laplace transform on formula (4) and formula (5) and eliminating the differential operators, we can obtain: （6） （7） Where, Represent the magnitude of the upper axial stress of the two vertical components 1 and 2 respectively; Indicates that time is transformed by Laplace transform Coefficients in the converted Laplace space; creep flexibility is an unknown variable; Calculate Equation (6) and Equation (7) using MATLAB to obtain creep flexibility The specific expression of .

4. The method according to claim 3, characterized in that Step S6 specifically includes: Step S61: Use the high-precision numerical integration method Talbot method to perform Laplace inverse transformation to obtain the creep flexibility of the two vertical components 1 and 2 in the time domain space. 、 : （8） （9） Where, represents the Laplace transform operator; Step S62: Calculate the total strain of vertical components 1 and 2 by calculating the axial force on the upper part of vertical components 1 and 2 and the shrinkage deformation of the components. 、 : （10） （11） Where, 、 Indicates the shrinkage deformation of a component, calculated through test results or standard formulas.

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