Tire and comb plate expansion joint vibration noise simulation method

Abstract

This invention proposes a method for simulating the vibration and noise of tires and toothed expansion joints. By establishing a tire-bridge deck finite element model, the tire deformation under load is obtained, and the results are compared and verified using empirical formulas. A tire-bridge deck-expansion joint finite element model is then constructed, setting the relative displacement between the bridge deck and the tire to simulate equivalent tire loading. Multiple analysis steps are set, gradually increasing the translational velocity of the bridge deck and expansion joint to simulate the rolling state of the tire on the bridge deck and expansion joint, calculating the vibration displacement of each node of the tire. The tire vibration displacement is used as a boundary condition and imported into acoustic calculation software. The boundary element method is then used to calculate the time-domain vibration noise of the tire passing over the bridge deck and expansion joint, and the results are compared with measured noise results. This invention can quickly determine the vibration and noise of toothed expansion joints under tire impact, with a difference of less than 10% compared to experimental results. It can be used for noise level prediction in the early stages of expansion joint design, facilitating the optimization of noise reduction expansion joint design.

Description

Technical Field

[0001] This invention belongs to the field of noise simulation, specifically relating to a method for simulating vibration noise of tires and comb-tooth plate type expansion joints. Background Technology

[0002] The noise generated by a vehicle during operation includes tire / road noise, mechanical noise, and aerodynamic noise, with tire / road noise accounting for over 90% of the total noise. Expansion joints, as crucial components and weak points of bridges, are responsible for accommodating bridge deformation. Because bridge expansion joints are perpendicular to the direction of travel and are mostly semi-rigid or rigid components, vehicles impact them, generating vibration noise. This structural vibration, in turn, affects the stability and safety of vehicle operation.

[0003] Current research on expansion joints, both domestically and internationally, mainly focuses on installation, damage monitoring, and repair / replacement. Research on the vibration and noise characteristics of expansion joints, especially those of toothed plate type expansion joints, is relatively limited, and most existing methods rely on outdoor monitoring. However, outdoor testing is significantly affected by site conditions, resulting in lower measurement accuracy. Therefore, to predict the noise characteristics of expansion joints during the design phase and optimize their noise reduction capabilities, a vibration and noise simulation method for tire-toothed plate type expansion joints is needed. Summary of the Invention

[0004] The purpose of this invention is to provide a method for simulating the vibration and noise of tires and toothed expansion joints, thereby solving the problem of low accuracy in noise monitoring results for toothed expansion joints in the prior art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a method for simulating vibration and noise of tires and toothed expansion joints, comprising the following steps:

[0006] S1. Establish a tire-bridge finite element model, apply internal pressure and load to the tire, and calculate the tire deformation amount by combining the empirical formula for tire deformation.

[0007] S2. Establish a bridge deck-comb plate expansion joint model and preset the material parameters and mesh generation for the model; then, based on the tire-bridge deck finite element model obtained in step S1, establish a tire-bridge deck-comb plate expansion joint finite element model and preset the contact conditions between the bridge deck and the comb plate expansion joint, between the tire and the bridge deck, and between the tire and the comb plate expansion joint.

[0008] S3. The load of the tire is equivalent to the vertical relative displacement between the tire and the bridge deck. By pre-setting multiple analysis steps, the translational velocity of the bridge deck and expansion joint is gradually increased to obtain the rolling state of the tire on the bridge deck and the expansion joint of the comb plate, and the vibration displacement of each node of the tire is calculated.

[0009] S4. Extract the tire surface mesh and import it into the acoustic simulation software. Set the field point plane and monitoring points. Use the vibration displacement of each node of the tire obtained in step S3 as the boundary condition. Use the boundary element method to calculate the sound source when the tire passes through the bridge deck and the expansion joint of the comb plate.

[0010] S5. Superimpose the sound sources when the tire passes through the bridge deck and the expansion joint of the comb plate, and compare the difference between the superimposed sound source result and the known preset result. If the difference is less than the preset difference, output the superimposed sound source result; otherwise, return to step S2.

[0011] Furthermore, the aforementioned step S1 includes the following sub-steps:

[0012] S101. Create a tire model and draw its mesh, then generate a finite element model;

[0013] S102. Establish a finite element model of the bridge deck and draw a mesh. After setting the material parameters of the tire and the bridge deck model, generate a tire-bridge deck finite element model.

[0014] S103. Inflate the tire to apply internal pressure and load, obtaining a deformed tire model. Compare its deformation with the calculation result of the empirical tire deformation formula obtained by Dunlap DF, as shown in the following formula:

[0015] ,

[0016] in, This represents the tire compression deformation, expressed in cm.

[0017] For tire design parameters,

[0018] W represents the load on the tire, measured in daN.

[0019] D is the outer diameter of the tire, in cm;

[0020] This refers to the tire width, in cm.

[0021] P is the tire internal pressure, in units of 100 kPa;

[0022] .

[0023] Furthermore, the aforementioned S2 includes the following sub-steps:

[0024] S201. Establish a bridge deck-comb plate expansion joint model, preset the material properties of the model and perform mesh generation, and refine the mesh on the top surface of the bridge deck model that contacts the tire.

[0025] S202. Based on the bridge deck-comb plate expansion joint model, and combined with the tire-bridge deck finite element model obtained in step S1, establish the tire-bridge deck-comb plate expansion joint finite element model, and preset the distance between the tire and the bridge deck.

[0026] S203. The comb-plate type expansion joint includes a movable comb plate and a fixed comb plate. The fixed comb plate and the bottom and side surfaces of the bridge deck pavement groove on this side, and the movable comb plate and the bottom and side surfaces of the bridge deck pavement groove on this side, are all constrained by tie. The bottom and side surfaces of the fixed comb plate and the bridge deck pavement groove on this side, the bottom and side surfaces of the movable comb plate and the bridge deck pavement groove on this side, the bottom surface of the movable comb plate and the bottom surface of the bridge deck pavement groove on the other side, the outer surface of the tire and the top surface of the bridge deck, and the outer surface of the tire and the top and side surfaces of the expansion joint are set as surface-to-surface contact, and the corresponding friction coefficient penalty function friction is defined.

[0027] Furthermore, the aforementioned step S3 includes the following sub-steps:

[0028] S301. Fix the tire center reference point and the bottom surface of the bridge pavement, and apply a uniformly distributed load as inflation pressure to the inner wall of the tire.

[0029] S302. Fix the tire center reference point and apply an upward displacement to the bottom surface of the bridge deck pavement so that the tire deforms under the action of the bridge deck, and the degree of deformation is consistent with the deformation amount described in step S1.

[0030] S303. Relax the rotational degree of freedom of the tire center reference point, allowing the tire to rotate around the central axis; relax the degree of freedom of the tire's forward direction on the underside of the bridge pavement, give the bridge pavement and expansion joint a small initial velocity in the opposite direction of the tire's forward movement, so that the tire starts to roll around the tire's central axis under the action of friction, and the bridge pavement and expansion joint and the tire undergo relative displacement.

[0031] S304. Based on step S303, set up multiple analysis steps, gradually increase the translational speed of the bridge deck pavement and expansion joints, so that the tire reaches the preset target speed before reaching the expansion joint, passes through the expansion joint at the target speed, and calculates the vibration displacement of each node of the tire.

[0032] Furthermore, the aforementioned step S4 includes the following sub-steps:

[0033] S401. Extract the tire surface mesh with a preset precision to form the tire boundary element.

[0034] S402. Draw the field point plane on the tire surface grid and select the monitoring points;

[0035] S403. Using the vibration displacement of each node of the tire obtained in step S3 as the boundary condition, perform acoustic response calculation and output the sound pressure level time domain response function to obtain the sound source when the tire passes through the bridge deck and the expansion joint of the comb plate.

[0036] Furthermore, step S5 as described above includes the following sub-steps:

[0037] S501. The four tires of a car traveling on the bridge are set as four identical sound sources; according to the principle of sound energy superposition, the total sound pressure level after the sound pressure levels of the four tires are superimposed is:

[0038] ;

[0039] in, Total sound pressure level, measured in dB(A);

[0040] The sound pressure level of sound source 1 is expressed in dB(A).

[0041] The sound pressure level of sound source 2 is expressed in dB(A).

[0042] The sound pressure level of sound source 3 is expressed in dB(A).

[0043] The sound pressure level of sound source 4 is expressed in dB(A).

[0044] Treating the four tires as four identical sound sources, i.e. = The total sound pressure level is then calculated as follows:

[0045] ;

[0046] S502. Considering the two tires of a car passing through an expansion joint simultaneously as two identical sound sources, and the other two tires traveling on the bridge surface as identical sound sources, the total sound pressure level after superimposing the sound pressure levels of the four tires is as follows, which is the result after superimposing the sound sources:

[0047] ;

[0048] S503. Compare the difference between the result of the sound source superposition and the known preset result. If the difference is less than the preset difference, output the result of the sound source superposition; otherwise, return to step S2.

[0049] Furthermore, in the aforementioned step S101, when establishing the tire model and drawing its mesh, and then generating the finite element model, the tire model is established using Solidworks software and the mesh is drawn in Hypermesh software, and the tire mesh is imported into the finite element software Abaqus in .inp format.

[0050] Further, the aforementioned step S403 specifically involves: adding a unit to the tire rim to close it off, importing it into the Acoustic Transient BEM module of LMSVirtual.lab, drawing the field point plane in this module, selecting monitoring points as needed, using the obtained tire displacement vibration response as boundary conditions, performing acoustic response calculations, outputting the sound pressure level time domain response function, and obtaining the sound source when the tire passes through the bridge deck and the expansion joint of the comb plate.

[0051] Furthermore, in the aforementioned step S5, the preset difference value is 10%.

[0052] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention uses the finite element method to simulate the vibration displacement characteristics of a tire passing through an expansion joint; it uses the boundary element method to simulate the noise characteristics of a tire passing through a bridge deck and an expansion joint, which can quickly obtain the vibration noise of the comb-plate type expansion joint under the impact of the tire, and can be used for noise level prediction in the early stage of expansion joint design, which is convenient for optimizing the design of noise reduction expansion joints. Attached Figure Description

[0053] Figure 1 This is a flowchart illustrating the implementation of the present invention;

[0054] Figure 2 For comb-tooth plate type expansion joints and the bridge deck paving at both ends;

[0055] Figure 3 Assembly drawing of the finite element model of tire-bridge deck-expansion joint;

[0056] Figure 4 This is a boundary element method sound field calculation model;

[0057] Figure 5 This is a time-domain distribution curve of noise at the monitoring point;

[0058] Figure 6 This is a comparison chart of the numerical simulation value and the experimental measured value of the noise sound pressure level after the sound sources are superimposed. Detailed Implementation

[0059] To better understand the technical content of the present invention, specific embodiments are described below in conjunction with the accompanying drawings.

[0060] In this invention, various aspects of the invention are described with reference to the accompanying drawings, in which numerous illustrative embodiments are shown. Embodiments of the invention are not limited to those depicted in the drawings. It should be understood that the invention is implemented through any of the various concepts and embodiments described above, as well as the concepts and embodiments described in detail below, because the concepts and embodiments disclosed herein are not limited to any particular implementation. Furthermore, some aspects of the invention disclosed may be used alone or in any suitable combination with other aspects of the invention disclosed.

[0061] like Figure 1 As shown in the flowchart of the present invention, a method for simulating vibration and noise of a tire and a toothed expansion joint includes the following steps:

[0062] S1. Establish a tire-bridge finite element model, apply internal pressure and load to the tire, and calculate the tire deformation using empirical formulas for tire deformation. This includes steps S101 to S103:

[0063] S101. Create a tire model and draw its mesh, then generate a finite element model: Use Solidworks software to create a tire model and Hypermesh software to draw the mesh. Import the tire mesh into the finite element software Abaqus in .inp format.

[0064] S102. Establish a finite element model of the bridge deck and draw a mesh. After setting the material parameters of the tire and bridge deck model, generate a tire-bridge deck finite element model: In Abaqus, establish a bridge deck model with a length of 2500mm, a width of 400mm, and a thickness of 200mm, and draw a mesh with the mesh type C3D8R. Assign material parameters to the tire and bridge deck model and then assemble them.

[0065] S103. Inflate the inner wall of the tire to a pressure of 220 kPa. Apply a load of 4000 N to the tire center reference point to obtain the deformed tire model. After the load is applied, the calculated radial displacement of the tire is 23.44 mm, which is basically consistent with the 23.41 mm calculated using the Dunlap DF tire deformation empirical formula, indicating that the tire model is reasonable. Compare its deformation amount with the calculation result of the tire deformation empirical formula obtained from Dunlap DF, as shown in the following formula:

[0066] ,

[0067] in, For tire design parameters, for radial tires =1.5;

[0068] W represents the load on the tire, measured in daN.

[0069] D is the tire's outer diameter, measured in cm.

[0070] This refers to the tire width, in centimeters.

[0071] P is the tire internal pressure, in units of 100 kPa;

[0072] .

[0073] S2. Establish a bridge deck-comb plate expansion joint model and preset material parameters and mesh generation for this model; then, based on the tire-bridge deck finite element model obtained in step S1, establish a tire-bridge deck-comb plate expansion joint finite element model, and preset the contact conditions between the bridge deck and the comb plate expansion joint, between the tire and the bridge deck, and between the tire and the comb plate expansion joint. Specifically, this includes the following sub-steps S201 to S203:

[0074] S201. Establish a bridge deck-comb plate expansion joint model, preset material properties for the model and perform mesh generation, and refine the mesh on the top surface of the bridge deck model in contact with the tires; for example... Figure 2 As shown, this embodiment establishes a model of two bridge deck sections and a comb-plate type expansion joint. Both bridge deck sections are 2500mm long, 400mm wide, and 200mm thick, with a 25mm high expansion joint slot reserved. The comb-plate type expansion device is 25mm thick, each comb tooth is 120mm long, the total length of the movable comb plate is 325mm, and the total length of the fixed comb plate is 195mm.

[0075] S202. Based on the bridge deck-comb plate expansion joint model, with a joint gap of 50mm, and combining the tire-bridge deck finite element model obtained in step S1, establish a tire-bridge deck-comb plate expansion joint finite element model, pre-setting the distance between the tire and the bridge deck; ensuring that the tire does not contact the bridge deck during the inflation stage, such as... Figure 3 As shown.

[0076] S203. The comb-plate type expansion joint includes a movable comb plate and a fixed comb plate. The fixed comb plate and the bottom and side surfaces of the bridge deck pavement groove on this side, and the movable comb plate and the bottom and side surfaces of the bridge deck pavement groove on this side, are all constrained using tie. The bottom and side surfaces of the fixed comb plate and the bridge deck pavement groove on this side, the bottom surface of the movable comb plate and the bottom surface of the bridge deck pavement groove on the other side, the outer surface of the tire and the top surface of the bridge deck, and the outer surface of the tire and the top and side surfaces of the expansion joint are set to face-to-face contact in the interaction module. At the same time, the corresponding friction coefficient penalty function friction is defined, where the friction coefficients are set to 0.6, 0.8, and 0.5, respectively.

[0077] S3. The load on the tire is equivalent to the vertical relative displacement between the tire and the bridge deck. Using the explicit solver in Abaqus software, multiple analysis steps are preset to gradually increase the translational velocity of the bridge deck and expansion joints, obtaining the rolling condition of the tire on the bridge deck and the expansion joints of the comb plate, and calculating the vibration displacement of each node of the tire. This includes the following sub-steps S301 to S304:

[0078] S301, with the duration set to 0.03s, fix the tire center reference point and the bottom surface of the bridge pavement, and apply a uniformly distributed load of 220kPa to the inner wall of the tire as the inflation pressure.

[0079] S302. Set the duration to 0.05s, fix the tire center reference point, apply an upward displacement to the bottom surface of the bridge deck pavement, so that the tire deforms under the action of the bridge deck, and the degree of deformation is consistent with the deformation amount described in step S1.

[0080] S303. Relax the rotational degree of freedom of the tire center reference point, allowing the tire to rotate around the central axis. Relax the degree of freedom of the tire's forward direction on the underside of the bridge pavement, and give the bridge pavement and expansion joint an initial velocity of 4.4 m / s in the opposite direction of the tire's forward movement, so that the tire begins to roll around the tire's central axis under the action of friction, and the bridge pavement and expansion joint and the tire undergo relative displacement.

[0081] S304. Based on step S303, set up multiple analysis steps, gradually increasing the translational speed of the bridge deck pavement and expansion joints, so that the tire reaches 40 km / h before reaching the expansion joint and passes through the expansion joint at a speed of 40 km / h. The tire vibration displacement response obtained in Abaqus software will be output in .odb format.

[0082] S4. Extract the tire surface mesh and import it into the acoustic simulation software. Set the field point plane and monitoring points. Use the vibration displacement of each node of the tire obtained in step S3 as the boundary condition. Use the boundary element method to calculate the sound source when the tire passes through the bridge deck and the expansion joint of the comb plate.

[0083] S401. Extract the tire surface mesh with preset precision in the hypermesh software to form the tire boundary element. To prevent sound leakage, add elements at the rim to make it closed. Import it into the AcousticTransient BEM module of LMS Virtual.lab software in .bdf format.

[0084] S402. Draw the field point plane on the tire tread grid and select monitoring points: Draw the field point grid in LMS Virtual.lab software. The field point plane is a 15m × 15m square plane 1.2m from the bottom of the tire, with the tire at the center of the plane. Select a location 7.5m from the tire on the grid as the monitoring point. Figure 4 As shown.

[0085] S403 imports the vibration displacements of each node of the tire obtained in step S3 into the LMS Virtual.lab software as boundary conditions to calculate the acoustic response and output the sound pressure level time-domain response function, such as... Figure 5 As shown, the sound source of the tire passing over the bridge deck and the expansion joint of the comb plate is obtained.

[0086] S5. Superimpose the sound sources when the tire passes through the bridge deck and the expansion joint of the comb plate, and compare the difference between the superimposed sound source result and the known preset result. If the difference is less than the preset difference, output the superimposed sound source result; otherwise, return to step S2.

[0087] This invention uses a passenger car as an example, considering the four tires of the passenger car as four sound sources. According to the principle of sound energy superposition, the total sound pressure level after the sound pressure levels of the four tires are superimposed is:

[0088]

[0089] in, Total sound pressure level, measured in dB(A);

[0090] The sound pressure level of sound source 1 is expressed in dB(A).

[0091] The sound pressure level of sound source 2 is expressed in dB(A).

[0092] The sound pressure level of sound source 3 is expressed in dB(A).

[0093] The sound pressure level of sound source 4 is expressed in dB(A).

[0094] When a car travels on a bridge, it treats its four tires as four identical sound sources. = The total sound pressure level is:

[0095] ;

[0096] like Figure 6 As shown, the noise level of the superimposed tires when they pass over the bridge surface is approximately 76 dB(A).

[0097] Then, considering the two tires of a car passing through the expansion joint simultaneously as two identical sound sources, and the other two tires traveling on the bridge surface as identical sound sources, the total sound pressure level after superimposing the sound pressure levels of the four tires is:

[0098] ;

[0099] like Figure 6 As shown, the noise level of the superimposed tires when they pass over the bridge surface is approximately 85 dB(A).

[0100] Finally, the differences between the superimposed bridge deck noise and expansion joint noise are compared with the known preset results, such as... Figure 6Determine whether the difference is less than a preset difference value, which is set to 10% in this embodiment; if yes, output the result after superimposing the sound sources; otherwise, return to step S2.

[0101] While the present invention has been described above with reference to preferred embodiments, it is not intended to limit the invention. Those skilled in the art can make various modifications and refinements without departing from the spirit and scope of the invention. Therefore, the scope of protection of the present invention shall be determined by the claims.

Claims

1. A method for simulating vibration and noise of tires and toothed expansion joints, characterized in that, Includes the following steps: S1. Establish a tire-bridge finite element model, apply internal pressure and load to the tire, and calculate the tire deformation amount by combining the empirical formula for tire deformation. S2. Establish a bridge deck-comb plate expansion joint model and preset the material parameters and mesh generation for the model; then, based on the tire-bridge deck finite element model obtained in step S1, establish a tire-bridge deck-comb plate expansion joint finite element model and preset the contact conditions between the bridge deck and the comb plate expansion joint, between the tire and the bridge deck, and between the tire and the comb plate expansion joint. S3. The load of the tire is equivalent to the vertical relative displacement between the tire and the bridge deck. By pre-setting multiple analysis steps, the translational velocity of the bridge deck and expansion joint is gradually increased to obtain the rolling state of the tire on the bridge deck and the expansion joint of the comb plate, and the vibration displacement of each node of the tire is calculated. S4. Extract the tire surface mesh and import it into the acoustic simulation software. Set the field point plane and monitoring points. Use the vibration displacement of each node of the tire obtained in step S3 as the boundary condition. Use the boundary element method to calculate the sound source when the tire passes through the bridge deck and the expansion joint of the comb plate. S5. Superimpose the sound sources when the tire passes through the bridge deck and the expansion joint of the comb plate, and compare the difference between the superimposed sound source result and the known preset result. If the difference is less than the preset difference, output the superimposed sound source result. Otherwise, return to step S2.

2. The method for simulating vibration and noise of tires and comb-tooth plate type expansion joints according to claim 1, characterized in that, Step S1 includes the following sub-steps: S101. Create a tire model and draw its mesh, then generate a finite element model; S102. Establish a finite element model of the bridge deck and draw a mesh. After setting the material parameters of the tire and the bridge deck model, generate a tire-bridge deck finite element model. S103. Inflate the tire to apply internal pressure and load, obtaining a deformed tire model. Compare its deformation with the calculation result of the empirical tire deformation formula obtained by Dunlap DF, as shown in the following formula: ， in, This represents the tire compression deformation, expressed in cm. For tire design parameters, W represents the load on the tire, measured in daN. D is the outer diameter of the tire, in cm; This refers to the tire width, in cm. P is the tire internal pressure, in units of 100 kPa; 。 3. The method for simulating vibration and noise of tires and comb-tooth plate type expansion joints according to claim 1, characterized in that, Step S2 includes the following sub-steps: S201. Establish a bridge deck-comb plate expansion joint model, preset the material properties of the model and perform mesh generation, and refine the mesh on the top surface of the bridge deck model that contacts the tire. S202. Based on the bridge deck-comb plate expansion joint model, and combined with the tire-bridge deck finite element model obtained in step S1, establish the tire-bridge deck-comb plate expansion joint finite element model, and preset the distance between the tire and the bridge deck. S203. The comb-plate type expansion joint includes a movable comb plate and a fixed comb plate. The fixed comb plate and the bottom and side surfaces of the bridge deck pavement groove on this side, and the movable comb plate and the bottom and side surfaces of the bridge deck pavement groove on this side, are all constrained by tie. The bottom and side surfaces of the fixed comb plate and the bridge deck pavement groove on this side, the bottom and side surfaces of the movable comb plate and the bridge deck pavement groove on this side, the bottom surface of the movable comb plate and the bottom surface of the bridge deck pavement groove on the other side, the outer surface of the tire and the top surface of the bridge deck, and the outer surface of the tire and the top and side surfaces of the expansion joint are set as surface-to-surface contact, and the corresponding friction coefficient penalty function friction is defined.

4. The method for simulating vibration and noise of tires and comb-tooth plate type expansion joints according to claim 3, characterized in that, Step S3 includes the following sub-steps: S301. Fix the tire center reference point and the bottom surface of the bridge pavement, and apply a uniformly distributed load as inflation pressure to the inner wall of the tire. S302. Fix the tire center reference point and apply an upward displacement to the bottom surface of the bridge deck pavement so that the tire deforms under the action of the bridge deck, and the degree of deformation is consistent with the deformation amount described in step S1. S303. Relax the rotational degree of freedom of the tire center reference point, allowing the tire to rotate around the central axis; relax the degree of freedom of the tire's forward direction on the underside of the bridge pavement, give the bridge pavement and expansion joint a small initial velocity in the opposite direction of the tire's forward movement, so that the tire starts to roll around the tire's central axis under the action of friction, and the bridge pavement and expansion joint and the tire undergo relative displacement. S304. Based on step S303, set up multiple analysis steps, gradually increase the translational speed of the bridge deck pavement and expansion joints, so that the tire reaches the preset target speed before reaching the expansion joint, passes through the expansion joint at the target speed, and calculates the vibration displacement of each node of the tire.

5. The method for simulating vibration and noise of tires and toothed expansion joints according to claim 4, characterized in that, Step S4 includes the following sub-steps: S401. Extract the tire surface mesh with a preset precision to form the tire boundary element. S402. Draw the field point plane on the tire surface grid and select the monitoring points; S403. Using the vibration displacement of each node of the tire obtained in step S3 as the boundary condition, perform acoustic response calculation and output the sound pressure level time domain response function to obtain the sound source when the tire passes through the bridge deck and the expansion joint of the comb plate.

6. The method for simulating vibration and noise of tires and comb-tooth plate type expansion joints according to claim 4, characterized in that, Step S5 includes the following sub-steps: S501. The four tires of a car traveling on the bridge are set as four identical sound sources; according to the principle of sound energy superposition, the total sound pressure level after the sound pressure levels of the four tires are superimposed is: ； in, Total sound pressure level, measured in dB(A); The sound pressure level of sound source 1 is expressed in dB(A). The sound pressure level of sound source 2 is expressed in dB(A). The sound pressure level of sound source 3 is expressed in dB(A). The sound pressure level of sound source 4 is expressed in dB(A). Treating the four tires as four identical sound sources, i.e. = The total sound pressure level is then calculated as follows: ； S502. Considering the two tires of a car passing through an expansion joint simultaneously as two identical sound sources, and the other two tires traveling on the bridge surface as identical sound sources, the total sound pressure level after superimposing the sound pressure levels of the four tires is as follows, which is the result after superimposing the sound sources: ； S503. Compare the difference between the result of the sound source superposition and the known preset result. If the difference is less than the preset difference, output the result of the sound source superposition; otherwise, return to step S2.

7. The method for simulating vibration and noise of tires and comb-tooth plate type expansion joints according to claim 2, characterized in that, In step S101, when establishing the tire model and drawing its mesh, and then generating the finite element model, the tire model is established using Solidworks software and the mesh is drawn in Hypermesh software. The tire mesh is then imported into the finite element software Abaqus in .inp format.

8. The method for simulating vibration and noise of tires and comb-tooth plate type expansion joints according to claim 5, characterized in that, Step S403 specifically involves: adding a unit to the tire rim to enclose it, importing it into the AcousticTransient BEM module of LMS Virtual.lab, drawing the field point plane in this module, selecting monitoring points as needed, using the obtained tire displacement vibration response as boundary conditions, performing acoustic response calculations, outputting the sound pressure level time domain response function, and obtaining the sound source when the tire passes over the bridge deck and the expansion joint of the comb plate.

9. The method for simulating vibration and noise of tires and comb-tooth plate type expansion joints according to claim 1, characterized in that, In step S5, the preset difference value is 10%.

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