Method for calculating vertical vibration caused by structural vehicle based on rod-suspension mass model

Abstract

The invention provides a structural vehicle-induced vertical vibration calculation method based on a rod-suspension mass model, and the method comprises the steps: simplifying a column in a building structure into a rod which moves axially along the building structure in the rod-suspension mass model, and exerting a fixed constraint at the bottom of the building structure; the method comprises the following steps of: assuming that each floor in a building structure is mainly in a local first-order vertical bending mode under vehicle-induced vertical vibration response, and simplifying each floor into a mass suspended at different height positions of a rod through a spring and a damper; the calculation method comprises the following steps: S1, acquiring parameters required for establishing a rod-suspension mass model; s2, establishing a motion equation of the rod-spring mass model; s3, calculating the dynamic response of the suspension mass; and S4, calculating the dynamic response of the floor slab. According to the method, by accurately describing the control mode of the dominant structure vehicle-induced vibration response, the degree of freedom of a power system is reduced, and the calculation efficiency is greatly improved.

Description

Technical Field

[0001] The present application relates to the field of building structures, and in particular to a method for calculating vehicle-induced vertical vibration of a structure based on a rod-suspension mass model. Background Art

[0002] With the construction of urban rail transit in China, the subway has not only facilitated people's travel, but also caused the vibration comfort problem of surrounding structures. People in an environment with large vibrations will feel nervous, bored or panic, which will affect work efficiency and may cause mental illness in the long run. As people's living standards improve, higher comfort requirements are put forward for the building environment. Therefore, it is an inevitable development trend to verify the vibration comfort of buildings around the subway during the structural design stage and carry out vibration reduction and isolation design when it exceeds the standard.

[0003] At present, the finite element method is usually used to model and calculate building structures. However, the finite element modeling process is cumbersome and the calculation efficiency is low, making it difficult to quickly complete the prediction of a large number of buildings. In addition, modeling based on the finite element method relies on a detailed description of the structural geometry and material properties. Although it can more accurately calculate the dynamic response of the structure, it lacks an intuitive explanation of the vibration mechanism and its influencing factors. This makes it difficult to formulate effective strategies when performing structural optimization or vibration reduction and isolation design based on vibration comfort.

[0004] The evaluation of vibration comfort needs to be targeted at the floor with the largest vertical vibration response, but the distribution law and influencing factors of the floor vibration response with the floor height are not clear at present. Actual measurements show that the maximum vehicle-induced response of buildings of different floors may occur at the bottom, middle or top floors. Due to the high frequency and wide range of vehicle-induced vibration loads, multiple vertical modes of the structure participate in the vibration. At present, the control mode of the dominant structural vibration response and the height distribution law is still unclear. In the horizontal seismic analysis of building structures, the candied haws string model, which simplifies each floor slab into a mass point and connects each other using the horizontal stiffness between layers, is a classic analysis model and plays an important role in the seismic design of structures and the development of seismic isolation measures. Even though numerical methods such as finite element have been widely used at this stage, the classic candied haws string model is still an effective means for mechanism analysis and rapid prediction in the early stage of structural design. However, there is no similar theoretical simplified model in the vertical vehicle-induced vibration analysis of building structures. The candied haws string model for horizontal seismic response analysis cannot meet the needs of vertical vehicle-induced vibration analysis.

[0005] In summary, the existing numerical models used for structural vehicle-induced vibration analysis are difficult to intuitively reflect the vibration response mechanism and make rapid predictions, and there is still a lack of a simplified theoretical model. Summary of the invention

[0006] The present application provides a method for calculating vehicle-induced vertical vibration of a structure based on a rod-suspension mass model, which can predict the dynamic response of a floor slab of a building structure under vehicle-induced ground vibration, thereby greatly improving the calculation efficiency.

[0007] The technical solution of this application is:

[0008] A method for calculating vehicle-induced vertical vibration of a structure based on a rod-suspended mass model, in which a column in a building structure is simplified into a rod that moves axially along the building structure, and a fixed constraint is applied to the bottom of the building structure; it is assumed that the floor slabs of each floor in the building structure are dominated by a local first-order vertical bending mode under the vehicle-induced vertical vibration response, and the floor slabs of each floor are simplified into masses suspended at different heights of the rod by springs and dampers; the method comprises the following steps:

[0009] S1, obtaining the parameters required to establish the rod-suspension mass model;

[0010] S2, establishing the equation of motion of the rod-suspension mass model;

[0011] S3, calculate the dynamic response of the suspended mass;

[0012] S4, calculate the dynamic response of the floor slab.

[0013] As a technical solution of the present application, in step S1, the required parameters of the rod-suspension mass model include the parameters of the rod and the simplified spring-mass-damping parameters of each floor slab:

[0014] The parameters of the rod include: the total building height H, the total cross-sectional area of ​​the column A, the elastic modulus E of the rod, and the linear density m of the column after correction by the mass of the floor that does not participate in the bending deformation. c ;

[0015] The simplified spring-mass-damper of each floor slab is suspended at the corresponding height of each floor slab, which is h from bottom to top. 1 、h 2 、h 3 ,…,h j ,…,h Nf And a total of N f The equivalent mass of each floor slab is m s,1 、m s,2 、m s,3 ,…,m s,j ,…,m s,Nf , which is the mass involved in the bending deformation, and the other residual mass not involved in the bending deformation is used to correct the linear density of the rod; the constraint stiffness of the column on the floor is equivalent to the stiffness coefficient of the suspension spring, and the stiffness coefficients of the suspension spring are k s,1 , ks,2 , k s,3 , …, k s,j , …, k s,Nf , the damping of the floor corresponds to the suspension damping coefficient and is c s,1 、c s,2 、c s,3 ,…,c s,j ,…,c s,Nf .

[0016] As a technical solution of the present application, in step S2, the axial displacement function of the rod is u(x, t), and the displacement of the jth suspended mass is w j (t), the system is subject to the vehicle-induced vertical acceleration of the ground Based on the relative motion method, the overall acceleration is applied to the system in the opposite direction; then the equation of motion is:

[0017]

[0018] Where: E is the elastic modulus of the rod, which is the elastic modulus of the column; A is the total cross-sectional area of ​​the column, which is the total cross-sectional area of ​​the column; u(x,t) is the axial displacement function of the rod; x is the vertical position; t is the time variable; m c is the linear density of the rod, which is taken based on the linear density of the column and takes into account the residual mass correction of the floor slab that does not participate in the bending deformation; N f is the number of floors; is the elastic force of the hanging mass on the rod; is the damping force of the suspended mass on the rod; is the vertical acceleration of the ground caused by the vehicle; m s,j is the equivalent mass of a floor slab; is the acceleration of the jth suspended mass; c s,j is the suspension damping coefficient corresponding to the damping of the j-th floor slab; is the velocity of the jth suspended mass; For the rod in h j Axial velocity at position; k s,j is the spring stiffness coefficient of the jth suspended mass; w j (t) is the displacement of the jth suspended mass; u(h j , t) is the rod at h j Axial displacement at position; where:

[0019]

[0020] Where: δ is the Dirac function; x is the vertical position; h j is the vertical position of the jth suspended mass; k s,j is the suspension spring stiffness coefficient; w j(t) is the displacement of the jth suspended mass; u(x,t) is the axial displacement function of the rod;

[0021]

[0022] Where: δ is the Dirac function; x is the vertical position; h j is the vertical position of the jth suspended mass; c s,j is the suspension damping coefficient corresponding to the damping of the j-th floor slab; is the velocity of the jth suspended mass; is the axial velocity of the rod;

[0023] For a cantilever rod vibrating axially, the i-th order natural frequency is:

[0024]

[0025] Where: w i c is the i-th order natural frequency; H is the total height of the building; E is the elastic modulus of the rod; A is the total cross-sectional area of ​​the column; m c is the linear density of the rod, and its value is taken based on the linear density of the column and takes into account the residual mass correction of the floor slab that does not participate in the bending deformation;

[0026] For a cantilever rod vibrating axially, the damping coefficient is:

[0027]

[0028] Where: c is the damping ratio of the column; m c is the linear density of the rod, and its value is taken based on the linear density of the column and takes into account the residual mass correction of the floor slab that does not participate in the bending deformation; w i c is the i-th order natural frequency;

[0029] Then the displacement function of the rod is:

[0030]

[0031] Where: q i (t) is the i-th order generalized coordinate; φ i (x) is the i-th order vibration mode function of the cantilever rod;

[0032] Considering the first N modes of the rod, the motion equation is simplified to:

[0033]

[0034] Where: U is the generalized coordinate vector, U=[q 1 ,q 2 ,...,q N,w 1 ,w 2 ,...,w Nf ] T ; Among them, the generalized mass matrix M, stiffness matrix K, damping matrix C and load vector F are as follows:

[0035]

[0036] Where: m c is the linear density of the rod, which is taken based on the linear density of the column and takes into account the residual mass correction of the floor slab that does not participate in the bending deformation; H is the total height of the building; m s,j is the equivalent mass of the j-th floor slab;

[0037]

[0038] Where: m c is the linear density of the rod, which is taken based on the linear density of the column and takes into account the residual mass correction of the floor slab that does not participate in the bending deformation; H is the total height of the building; w N c is the Nth order natural frequency; k s,j is the suspension spring stiffness coefficient;

[0039]

[0040] Where: h j is the vertical position of the jth suspended mass; H is the total height of the building;

[0041]

[0042] Where: is the nth vibration mode of the rod at h j Amplitude at position; is the mth vibration mode of the rod at h j Amplitude at position;

[0043]

[0044] Where: c is the damping ratio of the column; m c is the linear density of the rod, which is taken based on the linear density of the column and takes into account the residual mass correction of the floor slab that does not participate in the bending deformation; H is the total height of the building; w i c is the i-th order natural frequency; c s,j is the suspension damping coefficient corresponding to the damping of the j-th floor; k s,j is the suspension spring stiffness coefficient;

[0045]

[0046] Where: H is the total height of the building; m c is the linear density of the rod, which is taken based on the linear density of the column and takes into account the residual mass correction of the floor slab that does not participate in the bending deformation; m s,NF is the equivalent mass of the floor slabs on each floor; The system is subjected to the vertical acceleration of the ground caused by the vehicle.

[0047] As a technical solution of the present application, in step S3, based on the motion equation established in step S2, the dynamic response of the suspended mass is calculated by a numerical calculation method, and the numerical calculation method includes a modal superposition method, a Newmark-β method, and the like.

[0048] As a technical solution of the present application, in step S4, the first-order vertical bending vibration mode function of the floor is ψ(x s ,y s ), the mass distribution function is ρ s (x s ,y s ), where x s ,y s is the plane coordinate of the floor slab, and the area of ​​the slab is A s , then the equivalent mass of the plate is m s for:

[0049]

[0050] When the calculated velocity of the suspended mass is v s (t), then its kinetic energy is If the coordinates of the floor response observation point are (x 0 ,y 0 ), and its speed response is v 0 (t), then the kinetic energy of the floor is:

[0051]

[0052] By making the kinetic energy of the suspended mass equal to that of the floor, the response correction coefficient γ of the floor can be obtained as:

[0053]

[0054] The dynamic response at any position on the floor slab can be obtained by multiplying the suspended mass response obtained in step S3 by the correction coefficient γ.

[0055] Beneficial effects of this application:

[0056] The present application provides a method for calculating vehicle-induced vertical vibration of a structure based on a rod-suspension mass model, which can predict the dynamic response of the floor of a building structure under vehicle-induced ground vibration. This method reduces the degree of freedom of the dynamic system by accurately describing the control mode of the dominant structure's vehicle-induced vibration response; compared with the traditional finite element method, it greatly improves the calculation efficiency and intuitively reveals the interaction between the column mode and each floor mode, as well as the influence mechanism and influencing factors of each control mode on the height distribution of the vibration response. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the technical solutions of the implementation methods of the present application, the drawings required for use in the implementation methods will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0058] Figure 1 A schematic diagram of a rod-suspension mass model provided in an embodiment of the present application;

[0059] Figure 2 A schematic diagram of the acceleration time history of vehicle-induced ground vibration load provided in an embodiment of the present application;

[0060] Figure 3 A schematic diagram of a structural finite element model provided in an embodiment of the present application;

[0061] Figure 4 A schematic diagram of the comparison of the mid-span response time history of a floor slab provided in an embodiment of the present application;

[0062] Figure 5 A schematic diagram of the comparison of the mid-span response spectra of the floor slab provided in the embodiment of the present application. DETAILED DESCRIPTION

[0063] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0064] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0065] Example:

[0066] This embodiment provides a method for calculating vehicle-induced vertical vibration of a structure based on a rod-suspended mass model. In the rod-suspended mass model, a column in a building structure is simplified to a rod that moves axially along the building structure, and a fixed constraint is applied to the bottom of the building structure. It is assumed that the floor slabs of each floor in the building structure are mainly in a local first-order vertical bending mode under the vehicle-induced vertical vibration response, and the floor slabs of each floor are simplified to masses suspended at different heights of the rod by springs and dampers. The method comprises the following steps:

[0067] S1, obtain the parameters required to establish the rod-suspension mass model:

[0068] The required parameters of the rod-suspended mass model include the parameters of the rod and the simplified spring-mass-damper parameters of each floor slab:

[0069] The parameters of the rod include: the total building height H, the total cross-sectional area of ​​the column A, the elastic modulus E of the rod, and the linear density m of the column after correction by the mass of the floor that does not participate in the bending deformation. c ;

[0070] The simplified spring-mass-damper of each floor slab is suspended at the corresponding height of each floor slab, which is h from bottom to top. 1 、h 2 、h 3 ,…,h j ,…,h Nf And a total of N f The equivalent mass of each floor slab is m s,1 、m s,2 、m s,3 ,…,m s,j ,…,m s,Nf , which is the mass involved in the bending deformation, and the other residual mass not involved in the bending deformation is used to correct the linear density of the rod; the constraint stiffness of the column on the floor is equivalent to the stiffness coefficient of the suspension spring, and the stiffness coefficients of the suspension spring are k s,1 , k s,2 , k s,3 , …, k s,j , …, k s,Nf , the damping of the floor corresponds to the suspension damping coefficient and is c s,1 、c s,2 、c s,3 ,…,c s,j ,…,c s,Nf ;

[0071] S2, establish the equation of motion of the rod-suspension mass model:

[0072] The axial displacement function of the rod is u(x,t), and the displacement of the jth suspended mass is w j (t), the system is subject to the vertical acceleration of the ground caused by the vehicle Applying a reverse overall acceleration to the system based on the relative motion method;

[0073] Then the equation of motion is:

[0074]

[0075] Where: E is the elastic modulus of the rod, which is the elastic modulus of the column; A is the total cross-sectional area of ​​the column, which is the total cross-sectional area of ​​the column; u(x,t) is the axial displacement function of the rod; x is the vertical position; t is the time variable; m c is the linear density of the rod, which is taken based on the linear density of the column and takes into account the residual mass correction of the floor slab that does not participate in the bending deformation; N f is the number of floors; is the elastic force of the hanging mass on the rod; is the damping force of the suspended mass on the rod; is the vertical acceleration of the ground caused by the vehicle; m s,j is the equivalent mass of a floor slab; is the acceleration of the jth suspended mass; c s,j is the suspension damping coefficient corresponding to the damping of the j-th floor slab; is the velocity of the jth suspended mass; For the rod in h j Axial velocity at position; k s,j is the spring stiffness coefficient of the jth suspended mass; w j (t) is the displacement of the jth suspended mass; u(h j , t) is the rod at h j Axial displacement at position; where:

[0076]

[0077] Where: δ is the Dirac function; x is the vertical position; h j is the vertical position of the jth suspended mass; k s,j is the suspension spring stiffness coefficient; w j (t) is the displacement of the jth suspended mass; u(x,t) is the axial displacement function of the rod;

[0078]

[0079] Where: δ is the Dirac function; x is the vertical position; h j is the vertical position of the jth suspended mass; c s,j is the suspension damping coefficient corresponding to the damping of the j-th floor slab; is the velocity of the jth suspended mass; is the axial velocity of the rod;

[0080] For a cantilever rod vibrating axially, the i-th order natural frequency is:

[0081]

[0082] Where: w i c is the i-th order natural frequency; H is the total height of the building; E is the elastic modulus of the rod; A is the total cross-sectional area of ​​the column; m c is the linear density of the rod, and its value is taken based on the linear density of the column and takes into account the residual mass correction of the floor slab that does not participate in the bending deformation;

[0083] For a cantilever rod vibrating axially, the damping coefficient is:

[0084]

[0085] Where: c is the damping ratio of the column; m c is the linear density of the rod, and its value is taken based on the linear density of the column and takes into account the residual mass correction of the floor slab that does not participate in the bending deformation; w i c is the i-th order natural frequency;

[0086] Then the displacement function of the rod is:

[0087]

[0088] Where: q i (t) is the i-th order generalized coordinate; φ i (x) is the i-th order vibration mode function of the cantilever rod;

[0089] Considering the first N modes of the rod, the motion equation is simplified to:

[0090]

[0091] Where: U is the generalized coordinate vector, U=[q 1 ,q 2 ,...,q N ,w 1 ,w 2 ,...,w Nf ] T ; Among them, the generalized mass matrix M, stiffness matrix K, damping matrix C and load vector F are as follows:

[0092]

[0093] Where: mc is the linear density of the rod, which is taken based on the linear density of the column and takes into account the residual mass correction of the floor slab that does not participate in the bending deformation; H is the total height of the building; m s,j is the equivalent mass of the j-th floor slab;

[0094]

[0095] Where: m c is the linear density of the rod, which is taken based on the linear density of the column and takes into account the residual mass correction of the floor slab that does not participate in the bending deformation; H is the total height of the building; w N c is the Nth order natural frequency; k s,j is the suspension spring stiffness coefficient;

[0096]

[0097] Where: h j is the vertical position of the jth suspended mass; H is the total height of the building;

[0098]

[0099] Where: is the nth vibration mode of the rod at h j Amplitude at position; is the mth vibration mode of the rod at h j Amplitude at position;

[0100]

[0101] Where: c is the damping ratio of the column; m c is the linear density of the rod, which is taken based on the linear density of the column and takes into account the residual mass correction of the floor slab that does not participate in the bending deformation; H is the total height of the building; w i c is the i-th order natural frequency; c s,j is the suspension damping coefficient corresponding to the damping of the j-th floor; k s,j is the suspension spring stiffness coefficient;

[0102]

[0103] Where: H is the total height of the building; m c is the linear density of the rod, which is taken based on the linear density of the column and takes into account the residual mass correction of the floor slab that does not participate in the bending deformation; m s,NF is the equivalent mass of the floor slabs on each floor; The system is subjected to the vehicle-induced vertical acceleration of the ground;

[0104] S3, calculating the dynamic response of the suspended mass: based on the motion equation established in step S2, calculating the dynamic response of the suspended mass by a numerical calculation method, and the numerical calculation method includes a modal superposition method and a Newmark-β method;

[0105] S4, calculate the dynamic response of the floor:

[0106] The first-order vertical bending vibration function of the floor is ψ(x s ,y s ), the mass distribution function is ρ s (x s ,y s ), where x s ,y s is the plane coordinate of the floor slab, and the area of ​​the slab is A s , then the equivalent mass of the plate is m s for:

[0107]

[0108] When the calculated velocity of the suspended mass is v s (t), then its kinetic energy is If the coordinates of the floor response observation point are (x 0 ,y 0 ), and its speed response is v 0 (t), then the kinetic energy of the floor is:

[0109]

[0110] By making the kinetic energy of the suspended mass equal to that of the floor, the response correction coefficient γ of the floor can be obtained as:

[0111]

[0112] The dynamic response of any position on the floor slab can be obtained by multiplying the suspended mass response obtained in step S3 by the correction coefficient γ.

[0113] For details, please refer to Figure 1 , with reference Figures 2 to 5 , the above method is applied to a building structure with the following dimensions: 5 floors, 3.5m high; 4 columns, 0.4m×0.4m cross-sectional dimensions; 6m×6m floor slab, 0.2m thick; 0.4m×0.4m cross-sectional dimensions of floor slab edge beams. For reinforced concrete structures, the elastic modulus is 30kN / mm 2 ; Density: 2600kg / m 3 ; Poisson's ratio is 0.2. A set of measured vehicle-induced ground accelerations is used as loads, and the load-time curve is as follows Figure 3 shown.

[0114] Based on the various parameters of the above building structure, the rod-suspension mass model parameters of the building structure are obtained, as shown in Table 1 below:

[0115] Table 1 Parameters of rod-suspension mass model

[0116]

[0117] According to the above technical solution, the rod-suspended mass model is programmed using MATLAB software, and the above parameters are substituted into the motion equation of the rod-suspended mass model. The dynamic response of the floor span is calculated, and the response correction coefficient γ of the 1st to 4th floors is 1.53, and the response correction coefficient γ of the 5th floor is 1.56. The dynamic response is calculated using the Newmark-β method, and the calculation step is 0.005s. The Rayleigh damping model is used, and the damping ratio is set to 0.02.

[0118] At the same time, the commonly used finite element method is used to establish a calculation model to verify the accuracy of the rod-suspended mass model, and the advantages of the present invention are reflected by comparison. The finite element model is established using ANSYS software. In the finite element model, beams and columns use BEAM188 units, and floor slabs use SHELL181 units; the unit size is about 0.5m; the degree of freedom of the bottom of the column is constrained. The finite element model uses the same calculation step size and damping model as the rod-suspended mass model. The structural finite element model is as follows Figure 2 shown.

[0119] The structural natural frequencies and vehicle-induced vibration responses calculated by the rod-suspension mass model in this application are compared with those calculated by the finite element model. Table 2 shown below is a comparison of the structural natural frequencies in the frequency range of 1 to 80 Hz.

[0120] Table 2 Comparison of natural frequencies between rod-suspension mass model and finite element model

[0121]

[0122] As can be seen from Table 2, compared with the classic finite element model, the rod-suspended mass model proposed in this application can more accurately describe the natural frequency of the structure. Tables 3 and 4 below are the comparisons of the floor dynamic responses calculated by the two models. Figure 4 , Figure 5 The comparison diagram of the vibration response time history spectrum at the maximum response point (mid-span of the 5-story slab).

[0123] Table 3 Comparison of calculation results of the root mean square value of vibration acceleration at the mid-span of the floor

[0124]

[0125] Table 4 Comparison of calculation results of vibration acceleration level at mid-span of floor

[0126]

[0127]

[0128] From Table 3, Table 4 and Figure 4 , Figure 5 It can be seen that the rod-suspension mass model proposed in this application more accurately considers the control mode of the dominant vehicle-induced vibration response, and the frequency spectrum characteristics and height distribution law of the floor response are consistent with the finite element analysis results, and the accuracy meets the needs of vibration comfort evaluation. Using the same computer for calculation, the finite element model takes 6 minutes and 32 seconds, while the calculation time of the rod-suspension mass model is only 0.09 seconds.

[0129] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for calculating vehicle-induced vertical vibration of a structure based on a rod-suspension mass model, characterized in that: In the rod-suspended mass model, the columns in the building structure are simplified to rods that move axially along the building structure, and a fixed constraint is applied to the bottom of the building structure; it is assumed that the floor slabs of each floor in the building structure are dominated by the local first-order vertical bending mode under the vehicle-induced vertical vibration response, and the floor slabs of each floor are simplified to masses suspended at different heights of the rods by springs and dampers; It includes the following steps: S1, obtaining the parameters required to establish the rod-suspension mass model; S2, establishing the equation of motion of the rod-suspension mass model; S3, calculate the dynamic response of the suspended mass; S4, calculate the dynamic response of the floor slab.

2. The method for calculating the structural vehicle-induced vertical vibration based on the rod-suspension mass model according to claim 1 is characterized in that: In step S1, the required parameters of the rod-suspension mass model include the parameters of the rod and the simplified spring-mass-damping parameters of each floor slab: The parameters of the rod include: the total building height H, the total cross-sectional area of ​​the column A, the elastic modulus E of the rod, and the linear density m of the column after correction by the mass of the floor that does not participate in the bending deformation. c ; The simplified spring-mass-damper of each floor slab is suspended at the corresponding height of each floor slab, which is h1, h2, h3, ..., h from bottom to top. j ,…,h Nf And a total of N f The equivalent mass of each floor slab is m s,1 、m s,2 、m s,3 ,…,m s,j ,…,m s,Nf , which is the mass involved in the bending deformation; the constraint stiffness of the column on the floor is equivalent to the stiffness coefficient of the suspension spring, and the stiffness coefficients of the suspension spring are k s,1 , k s,2 , k s,3 , …, k s,j , …, k s,Nf , the damping of the floor corresponds to the suspension damping coefficient and is c s,1 、c s,2 、c s,3 ,…,c s,j ,…,c s,Nf .

3. The method for calculating the structural vehicle-induced vertical vibration based on the rod-suspension mass model according to claim 1 is characterized in that: In step S2, the axial displacement function of the rod is u(x,t), and the displacement of the jth suspended mass is w j (t), the system is subject to the vehicle-induced vertical acceleration of the ground Based on the relative motion method, the overall acceleration is applied to the system in the opposite direction; then the equation of motion is: Where: E is the elastic modulus of the rod, which is the elastic modulus of the column; A is the total cross-sectional area of ​​the column, which is the total cross-sectional area of ​​the column; u(x,t) is the axial displacement function of the rod; x is the vertical position; t is the time variable; m c is the linear density of the rod; N f is the number of floors; is the elastic force of the hanging mass on the rod; is the damping force of the suspended mass on the rod; is the vertical acceleration of the ground caused by the vehicle; m s,j is the equivalent mass of a floor slab; is the acceleration of the jth suspended mass; c s,j is the suspension damping coefficient corresponding to the damping of the j-th floor slab; is the velocity of the jth suspended mass; For the rod in h j Axial velocity at position; k s,j is the spring stiffness coefficient of the jth suspended mass; w j (t) is the displacement of the jth suspended mass; u(h j , t) is the rod at h j Axial displacement at position; where: Where: δ is the Dirac function; x is the vertical position; h j is the vertical position of the jth suspended mass; k s,j is the suspension spring stiffness coefficient; w j (t) is the displacement of the jth suspended mass; u(x,t) is the axial displacement function of the rod; Where: δ is the Dirac function; x is the vertical position; h j is the vertical position of the jth suspended mass; c s,j is the suspension damping coefficient corresponding to the damping of the j-th floor slab; is the velocity of the jth suspended mass; is the axial velocity of the rod; For a cantilever rod vibrating axially, the i-th order natural frequency is: Where: w i c is the i-th order natural frequency; H is the total height of the building; E is the elastic modulus of the rod; A is the total cross-sectional area of ​​the column; m c is the linear density of the rod; For a cantilever rod vibrating axially, the damping coefficient is: Where: c is the damping ratio of the column; m c is the linear density of the rod; w i c is the i-th order natural frequency; Then the displacement function of the rod is: Where: q i (t) is the i-th order generalized coordinate; φ i (x) is the i-th order vibration mode function of the cantilever rod; Considering the first N modes of the rod, the motion equation is simplified to: Where: U is the generalized coordinate vector, U=[q1,q2,...,q N ,w1,w2,...,w Nf ] T ; Among them, the generalized mass matrix M, stiffness matrix K, damping matrix C and load vector F are as follows: Where: m c is the linear density of the poles; H is the total height of the building; m s,j is the equivalent mass of the j-th floor slab; Where: m c is the linear density of the poles; H is the total height of the building; w N c is the Nth order natural frequency; k s,j is the suspension spring stiffness coefficient; Where: h j is the vertical position of the jth suspended mass; H is the total height of the building; Where: is the nth vibration mode of the rod at h j Amplitude at position; is the mth vibration mode of the rod at h j Amplitude at position; Where: c is the damping ratio of the column; m c is the linear density of the poles; H is the total height of the building; w i c is the i-th order natural frequency; c s,j is the suspension damping coefficient corresponding to the damping of the j-th floor; k s,j is the suspension spring stiffness coefficient; Where: H is the total height of the building; m c is the linear density of the rod; m s,NF is the equivalent mass of the floor slabs on each floor; The system is subjected to the vertical acceleration of the ground caused by the vehicle.

4. The method for calculating the structural vehicle-induced vertical vibration based on the rod-suspension mass model according to claim 1 is characterized in that: In step S3, based on the motion equation established in step S2, the dynamic response of the suspended mass is calculated by a numerical calculation method, and the numerical calculation method includes a modal superposition method and a Newmark-β method.

5. The method for calculating the structural vehicle-induced vertical vibration based on the rod-suspension mass model according to claim 1 is characterized in that: In step S4, the first-order vertical bending vibration function of the floor is ψ(x s ,y s ), the mass distribution function is ρ s (x s ,y s ), where x s ,y s is the plane coordinate of the floor slab, and the area of ​​the slab is A s , then the equivalent mass of the plate is m s for: When the calculated velocity of the suspended mass is v s (t), then its kinetic energy is If the coordinates of the floor response observation point are (x0, y0), and its velocity response is v0(t), then the kinetic energy of the floor is: By making the kinetic energy of the suspended mass equal to that of the floor, the response correction coefficient γ of the floor can be obtained as: The dynamic response at any position on the floor slab can be obtained by multiplying the suspended mass response obtained in step S3 by the correction coefficient γ.

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