A method for evaluating the whole-path engineering vibration response of movable cultural relics in museum collections

Abstract

This invention discloses a method for evaluating the full-path engineering vibration response of movable cultural relics in museum collections. This method is a numerical simulation approach covering the entire path from vibration source to museum, storage cabinet, enclosure, and relic. First, it simulates the forces experienced by the museum during construction by simulating the vibration source at other sites, thus filling a gap in the computational framework. Then, it calculates the frequency response functions of the storage cabinet and enclosure, integrating these two key components into the calculation process. This addresses the problem in existing research where floor vibrations are equated to vibrations from movable cultural relics, leading to inconsistencies between the model and reality. This invention can more accurately evaluate the true dynamic response of movable cultural relics in museum collections under construction vibrations.

Description

Technical Field

[0001] This invention belongs to the field of cultural relic vibration protection technology, specifically involving a method for evaluating the full-path engineering vibration response of movable cultural relics in museum collections. Background Technology

[0002] Currently, there are two main research methods for studying the impact of engineering vibrations on movable cultural relics in museum collections.

[0003] The first method is on-site monitoring and vibration testing, which involves deploying sensors (such as accelerometers) around or on the structure of the cultural relic to directly measure the vibration data generated by vibration sources such as subways, engineering construction, and transportation, and to assess their propagation laws and the actual response of the cultural relic. This is the basic means of obtaining real data.

[0004] For example, in order to assess the impact of the vibration of the Shijiazhuang Metro Line 1 operation on the Hebei Provincial Museum, which is about 50 meters away, Xu Qiang et al. set up observation points on the second basement level of the plaza in front of the museum and used a MENHIR measuring instrument (with a built-in three-dimensional accelerometer) to conduct continuous monitoring throughout the day to obtain vibration acceleration data. Through on-site measurement data, they analyzed the vibration propagation law and assessed the intensity of the vibration impact with reference to the "China Seismic Intensity Scale", providing direct evidence for the long-term protection of museum cultural relics.

[0005] The second method is to use numerical simulation to evaluate the vibration wave propagation path, structural dynamic response, and potential damage by establishing an overall finite element model using finite element software.

[0006] For example, Wang Jianchao et al., in order to predict the vibrations caused by subway operation from a theoretical perspective, and to investigate how these vibrations propagate through the ground and affect the structure of adjacent museum buildings, established a refined three-dimensional finite element numerical model encompassing the "subway train-track-tunnel-ground-museum building." Using the subway operating load as an excitation, they calculated the response (such as acceleration and velocity time history) of the vibration waves propagating to the building foundation and passing through each floor of the building through dynamic time history analysis. This was the first time that the complete propagation mechanism and attenuation law of vibration from the vibration source to the building structure were systematically revealed at the numerical level. It can predict the differences in vibration magnitude at different floors and locations, providing a theoretical basis for assessing the "macro-environment" of cultural relic storage. The endpoint of their analysis is the vibration response of the building structure.

[0007] The above-mentioned existing technologies have the following drawbacks: 1. Existing technologies assess the impact of engineering vibrations on movable cultural relics by deploying sensors around or on the structure of the relics to directly measure vibration data generated by vibration sources such as subways, construction projects, and transportation. This method requires on-site testing near the museum or simulation testing of construction vibrations. Construction vibration simulation involves simulating the required construction conditions on-site and then conducting tests to obtain results. Therefore, both on-site testing and simulation generate vibrations that could potentially harm the cultural relics.

[0008] 2. Although existing technologies use numerical simulation methods to assess the impact of engineering vibrations on museum artifacts, they only consider the force transmission path from the vibration source to the museum floor to the artifact. This directly equates the vibration response of the museum floor to the vibration input of the storage cabinet. However, as intermediate links, the dynamic characteristics of the artifact storage cabinet and the storage cabinet themselves will produce complex effects such as filtering, amplification, or attenuation of the vibration. Without considering the influence of the artifact storage cabinet and the storage cabinet in the force transmission process, it will be difficult to accurately assess the true dynamic response of movable artifacts under engineering vibrations. Summary of the Invention

[0009] This invention discloses a method for evaluating the full-path engineering vibration response of movable cultural relics in museum collections. This method is a numerical simulation approach covering the entire path from vibration source to museum, storage cabinet, enclosure, and relic. First, the forces experienced by the museum during construction are simulated by using vibration sources at other sites, thus filling a gap in the computational framework. Then, the frequency response functions of the storage cabinet and enclosure are calculated, incorporating these two key components into the calculation process. This addresses the discrepancy between the model and reality caused by existing research equating floor vibrations to vibrations of movable cultural relics.

[0010] To achieve the above objectives, the technical solution of the present invention is as follows: A method for assessing the full-path engineering vibration response of movable cultural relics in museum collections includes the following steps: Step 1. Simulation of vibration sources during engineering construction; Step 2. Simulate the dynamic response of the museum structure under the vibration source during construction; Step 3. Frequency response function test of the artifact storage cabinet and case; Step 4. Calculate the dynamic response of the museum-artifact storage cabinet-casket system.

[0011] Preferably, step 1 includes the following specific steps: Step 11. Determine soil layer information: Obtain the basic parameters of the soil layers at the test site based on the project's geological survey report; Step 12. Determine working condition information: Based on the construction plan, determine the required simulated engineering construction conditions and vibration source distance; Step 13. Measurement point arrangement: With the vibration source as the center, arrange a measurement point every 5 meters; Step 14. Data Acquisition and Processing: Conduct simulated vibration tests under corresponding engineering conditions at the test site. Convert the acquired signals into digital signals using a data acquisition instrument. Then, process the signals through windowing, correction, smoothing, filtering, and truncation to obtain preprocessed digital signals. Step 15. Establishment of dynamic finite element model of soil: Establish a dynamic finite element model of soil based on the geological survey report of the test site. Apply viscoelastic artificial boundary at the boundary of the model. Set spring and damping elements in the normal and tangential directions of the boundary nodes of the model to simulate the effect of the infinite domain on the computational domain. Consider the spring stiffness and damping coefficient of a single point. Calculate the damping ratio of the soil layer by Rayleigh damping. Step 16. Determine the engineering load using the reverse calibration method, as shown in the following formula: ; In the formula, —Equivalent input load; —Equivalent coefficient; —Equivalent mass, the mass unit within the model is ; —Equivalent acceleration; The obtained vibration load is simplified into a surface load form and input into the soil dynamic finite element model, with pre-set... The value is 1, The equivalent input load of the measured value is input into the model, the data of each measuring point is compared with the model data, and the average value of the ratio of each point is taken as the average value. Values ​​are determined based on The equivalent input load is calculated by taking the values.

[0012] Preferably, step 2 includes the following specific steps: Step 21. Geometric model construction of the museum's dynamic finite element model structure: Based on the museum's architectural structural drawings (CAD drawings or BIM model), establish the geometric model of the structure in finite element preprocessing software (such as ABAQUS / CAE, ANSYS Workbench, MSCPatran, etc.); Step 22. Simplification of the structural geometric model: Based on the principles of structural mechanics, one-dimensional components such as beams and columns are abstracted as their centerlines and simulated using beam elements; two-dimensional components such as floor slabs and shear walls are abstracted as their surfaces and simulated using shell elements; irregularly shaped components are decomposed into combinations of regular geometric shapes. This method greatly improves modeling and calculation efficiency while preserving the main mechanical behaviors. Based on the judgment of the significant impact on the overall structural stiffness and low-order modes, decorative holes, small chamfers, and geometric details such as moldings are removed; these features may cause local stress concentrations, but their contribution to the overall dynamic response of the structure (such as the fundamental period and overall mode shape) is negligible. After simplification, the key inertial parameters of the model are verified, and the error between the total mass and the design value should be less than [value missing]. The deviation between the center of gravity position and the design value should be controlled within a small range (e.g., Overall dimensions of the model The error in rotational inertia, including the moment of inertia about the center of gravity, is less than [a certain value]. ; Step 23. Determine the material type: Based on the design drawings, specify the material of each structural component (e.g., ...). concrete (steel, masonry, etc.) Step 24. Define basic linear elastic parameters: Based on the "Code for Design of Concrete Structures" and the "Standard for Design of Steel Structures", assign an elastic modulus to each material. Poisson's ratio and mass density ; Step 25. Define the structural damping ratio: For the linear response analysis of most building structures under micro-vibrations, the Rayleigh damping model is adopted, and the damping ratio is... Based on the "Code for Seismic Design of Buildings" and experience with similar structures, a damping coefficient of 3% is adopted, and the Rayleigh damping coefficient is... and Calculated using the following formula: ; in, ω is the damping ratio of the i-th mode; α is the mass proportional damping coefficient; β is the stiffness proportional damping coefficient; i Let be the i-th natural angular frequency, derived from the first two natural frequencies. Determine that the damping ratio is exactly equal to the damping ratio at these two frequencies. ; Step 26. Determine the element type: Beams and columns: use 3D beam elements that consider shear deformation; Floor slabs, shear walls, and roofs: use shell elements; Solid parts (such as foundations and thick walls): use solid elements; Step 27. Define and assign section properties: Define the actual cross-sectional shape and size for beams and columns; define the thickness for shell elements; and assign the defined section properties to the corresponding geometric components. Step 28. Mesh Generation and Control: Mesh generation adopts a strategy of primarily using structured meshes supplemented by free meshes; the convergent mesh size is determined through system mesh sensitivity analysis: after two consecutive mesh refinements, the change in the first N natural frequencies is less than [a certain value]. As a convergence criterion, when generating the final mesh, it is necessary to strictly check the element aspect ratio and Jacobian ratio, and optimize the mesh layout while ensuring accuracy, so as to control the scale of the total degrees of freedom and ensure the computational feasibility of subsequent large-scale dynamic time history analysis. Step 29. Define boundary conditions: Define fixed, elastic, or seismic isolation bearings according to the geological survey report and foundation design, and correctly simulate the connection between structural components (rigid connection, hinged connection, sliding connection, etc.). Step 210. Perform modal analysis to verify the rationality of the modeling: If the modal analysis results deviate from the empirical or measured values ​​by more than 10%, the material parameters, connection conditions, and mesh quality need to be checked again until the dynamic characteristics of the model are confirmed to be reasonable; this step is the key to ensuring the credibility of all subsequent dynamic response analyses.

[0013] Step 211. Load Input: Simplify the input loads obtained from the vibration source of the simulated engineering construction into surface loads and input them to the bottom of the model; Step 212. Structural Dynamic Time History Analysis and Data Processing: Set up the analysis steps and run the model for finite element analysis. Set output points at the center of each floor slab or typical locations in the model, and extract these points. The acceleration time history response in three directions transforms the output time domain of each floor into the corresponding output frequency domain through fast Fourier transform, and this frequency domain is equivalent to the input frequency domain of each floor-artifact storage cabinet-case system.

[0014] Preferably, step 3 includes the following specific steps: Step 31. Data Acquisition: Set up measuring points on the ground, in the case, and in the artifact storage cabinet. Apply a controllable excitation signal to the system using a vibrator, and simultaneously acquire the excitation force signal. The response signals of the case and the artifact storage cabinet ; Step 32 calculates the frequency response function, as shown in the following formula: ; For a response signal Perform Fourier transform to obtain Its self-power spectrum Approximately Conjugate with The average of the products is: ; For two signals Input and Output, its cross-power spectrum It is the spectrum of the input signal. With the output signal spectrum conjugate The average of the products, i.e. ; pass Calculate the frequency response functions of the casket and the artifact storage cabinet respectively. ; Step 33. Establish the frequency response function of the floor-artifact storage cabinet-casket system: Use the product of the frequency response functions of the casket and the artifact storage cabinet to represent the equivalent frequency response function of the floor-artifact storage cabinet-casket system, i.e. .

[0015] Preferably, step 4 includes the following specific steps: Step 41. Calculate the output frequency domain of the floor-artifact storage cabinet-casket system: Multiply the input frequency domain of the floor-artifact storage cabinet-casket system with the frequency response function of the floor-artifact storage cabinet-casket system to obtain the output frequency domain of the floor-artifact storage cabinet-casket system; Step 42. Calculate the output time domain of the floor-artifact storage cabinet-casket system: Transform the output frequency domain of the floor-artifact storage cabinet-casket system into the output time domain of the floor-artifact storage cabinet-casket system through inverse Fourier transform, which is the vibration velocity of the artifacts acting in the casket.

[0016] The beneficial effects of the present invention, a method for evaluating the whole-path engineering vibration response of movable cultural relics in museum collections, are as follows: 1. This invention provides a method for simulating vibration sources in engineering construction. By simulating engineering construction conditions at other sites and using a reverse calibration method to obtain the required input load, it fills the gap in research on how to simulate vibrations in engineering construction and avoids the potential harm to cultural relics caused by vibrations generated during on-site testing or simulation.

[0017] 2. This invention provides a numerical simulation method for the entire path of "vibration source - museum - artifact storage cabinet - case - artifact". By obtaining the frequency response functions of the case and artifact storage cabinet and incorporating them into the calculation process, these two key links are taken into account in the entire path process, thus improving the force transmission path and achieving the effect of more accurately evaluating the real dynamic response of movable artifacts in the collection under the vibration of engineering construction. Attached Figure Description

[0018] Figure 1 A flowchart of the method of the present invention; Figure 2 , Capsule frequency response function (in the figure, (a) is vertical; (b) is horizontal); Figure 3 The vibration time history curve is selected for rotary drilling pile working conditions; Figure 4 The time histories of the vertical and horizontal velocity at the F1 output point (in the figure, (a) is vertical; (b) is horizontal). Figure 5 , Capsule frequency response function (in the figure, (a) is vertical; (b) is horizontal); Figure 6 Vibration response of cultural relics ((a) Vertical output time domain curve of floor-cultural relic storage cabinet-casket system; (b) Horizontal output time domain curve of floor-cultural relic storage cabinet-casket system). Detailed Implementation

[0019] The following description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0020] Example 1: A method for assessing the full-path engineering vibration response of movable cultural relics in museum collections, such as... Figure 1 As shown, it includes the following steps: Step 1. Simulation of vibration sources during engineering construction; Step 2. Simulate the dynamic response of the museum structure under the vibration source during construction; Step 3. Frequency response function test of the artifact storage cabinet and case; Step 4. Calculate the dynamic response of the museum-artifact storage cabinet-casket system.

[0021] Example 2: Based on Example 1, such as Figure 1 As shown, step 1 includes the following specific steps: Step 11. Determine soil layer information: Obtain the basic parameters of the soil layers at the test site based on the project's geological survey report; Step 12. Determine working condition information: Based on the construction plan, determine the required simulated engineering construction conditions and vibration source distance; Step 13. Measurement point arrangement: With the vibration source as the center, arrange a measurement point every 5 meters; Step 14. Data Acquisition and Processing: Conduct simulated vibration tests under corresponding engineering conditions at the test site. Convert the acquired signals into digital signals using a data acquisition instrument. Then, process the signals by applying windowing functions, correction, smoothing, filtering, and truncation to obtain the processed digital signals. Step 15. Establishment of dynamic finite element model of soil: Establish a dynamic finite element model of soil based on the geological survey report of the test site. Apply viscoelastic artificial boundary at the boundary of the model. Set spring and damping elements in the normal and tangential directions of the boundary nodes of the model to simulate the effect of the infinite domain on the computational domain. Consider the spring stiffness and damping coefficient of a single point. Calculate the damping ratio of the soil layer by Rayleigh damping. Step 16. Determine the engineering load using the reverse calibration method, as shown in the following formula: ; In the formula, —Equivalent input load; —Equivalent coefficient; —Equivalent mass, the mass unit within the model is ; —Equivalent acceleration; The obtained vibration load is simplified into a surface load form and input into the soil dynamic finite element model, with pre-set... The value is 1, The equivalent input load of the measured value is input into the model, the data of each measuring point is compared with the model data, and the average value of the ratio of each point is taken as the average value. Values ​​are determined based on The equivalent input load is calculated by taking the values.

[0022] Example 3: Based on Example 1, such as Figure 1 As shown, step 2 includes the following specific steps: Step 21. Geometric model construction of the museum's dynamic finite element model structure: Based on the museum's architectural structural drawings (CAD drawings or BIM model), establish the geometric model of the structure in finite element preprocessing software (such as ABAQUS / CAE, ANSYS Workbench, MSCPatran, etc.); Step 22. Simplification of the structural geometric model: Based on the principles of structural mechanics, one-dimensional components such as beams and columns are abstracted as their centerlines and simulated using beam elements; two-dimensional components such as floor slabs and shear walls are abstracted as their surfaces and simulated using shell elements; irregularly shaped components are decomposed into combinations of regular geometric shapes. This method greatly improves modeling and calculation efficiency while preserving the main mechanical behaviors. Based on the judgment of the significant impact on the overall structural stiffness and low-order modes, decorative holes, small chamfers, and geometric details such as moldings are removed; these features may cause local stress concentrations, but their contribution to the overall dynamic response of the structure (such as the fundamental period and overall mode shape) is negligible. After simplification, the key inertial parameters of the model are verified, and the error between the total mass and the design value should be less than [value missing]. The deviation between the center of gravity position and the design value should be controlled within a small range (e.g., Overall dimensions of the model The moment of inertia, including the moment of inertia about the center of gravity, has an error of less than [missing information]. ; Step 23. Determine the material type: Based on the design drawings, specify the material of each structural component (e.g., ...). concrete (steel, masonry, etc.) Step 24. Define basic linear elastic parameters: Based on the "Code for Design of Concrete Structures" and the "Standard for Design of Steel Structures", assign an elastic modulus to each material. Poisson's ratio and mass density ; Step 25. Define the structural damping ratio: For the linear response analysis of most building structures under micro-vibrations, the Rayleigh damping model is adopted, and the damping ratio is... Based on the "Code for Seismic Design of Buildings" and experience with similar structures, the following is adopted: Rayleigh damping coefficient and Calculated using the following formula: ; in, ω is the damping ratio of the i-th mode; α is the mass proportional damping coefficient; β is the stiffness proportional damping coefficient; i Let be the i-th natural angular frequency, derived from the first two natural frequencies. Determine that the damping ratio is exactly equal to the damping ratio at these two frequencies. ; Step 26. Determine the element type: Beams and columns: use 3D beam elements that consider shear deformation; Floor slabs, shear walls, and roofs: use shell elements; Solid parts (such as foundations and thick walls): use solid elements; Step 27. Define and assign section properties: Define the actual cross-sectional shape and size for beams and columns; define the thickness for shell elements; and assign the defined section properties to the corresponding geometric components. Step 28. Mesh Generation and Control: Mesh generation adopts a strategy of primarily using structured meshes supplemented by free meshes; the convergent mesh size is determined through system mesh sensitivity analysis: after two consecutive mesh refinements, the change in the first N natural frequencies is less than [a certain value]. As a convergence criterion, when generating the final mesh, it is necessary to strictly check the element aspect ratio and Jacobian ratio, and optimize the mesh layout while ensuring accuracy, so as to control the scale of the total degrees of freedom and ensure the computational feasibility of subsequent large-scale dynamic time history analysis. Step 29. Define boundary conditions: Define fixed, elastic, or seismic isolation bearings according to the geological survey report and foundation design, and correctly simulate the connection between structural components (rigid connection, hinged connection, sliding connection, etc.). Step 210. Perform modal analysis to verify the rationality of the modeling: If the modal analysis results deviate from the empirical or measured values ​​by more than 10%, the material parameters, connection conditions, and mesh quality need to be checked again until the dynamic characteristics of the model are confirmed to be reasonable; this step is the key to ensuring the credibility of all subsequent dynamic response analyses.

[0023] Step 211. Load Input: Simplify the input loads obtained from the vibration source of the simulated engineering construction into surface loads and input them to the bottom of the model; Step 212. Structural Dynamic Time History Analysis and Data Processing: Set up the analysis steps and run the model for finite element analysis. Set output points at the center of each floor slab or typical locations in the model, and extract these points. The acceleration time history response in three directions transforms the output time domain of each floor into the corresponding output frequency domain through fast Fourier transform, and this frequency domain is equivalent to the input frequency domain of each floor-artifact storage cabinet-case system.

[0024] Example 4: Based on Example 1, such as Figure 1 As shown, step 3 includes the following specific steps: Step 31. Data Acquisition: Set up measuring points on the ground, in the case, and in the artifact storage cabinet. Apply a controllable excitation signal to the system using a vibrator, and simultaneously acquire the excitation force signal. The response signals of the case and the artifact storage cabinet ; Step 32 calculates the frequency response function, as shown in the following formula: ; For a response signal Perform Fourier transform to obtain Its self-power spectrum Approximately Conjugate with The average of the products is: ; For two signals Input and Output, its cross-power spectrum It is the spectrum of the input signal. With the output signal spectrum conjugate The average of the products, i.e. ; pass Calculate the frequency response functions of the casket and the artifact storage cabinet respectively. ;like Figure 2 As shown; Step 33. Establish the frequency response function of the floor-artifact storage cabinet-casket system: Use the product of the frequency response functions of the casket and the artifact storage cabinet to represent the equivalent frequency response function of the floor-artifact storage cabinet-casket system, i.e. .

[0025] Example 5: Based on Example 1, such as Figure 1 As shown, step 4 includes the following specific steps: Step 41. Calculate the output frequency domain of the floor-artifact storage cabinet-casket system: Multiply the input frequency domain of the floor-artifact storage cabinet-casket system with the frequency response function of the floor-artifact storage cabinet-casket system to obtain the output frequency domain of the floor-artifact storage cabinet-casket system; Step 42. Calculate the output time domain of the floor-artifact storage cabinet-casket system: Transform the output frequency domain of the floor-artifact storage cabinet-casket system into the output time domain of the floor-artifact storage cabinet-casket system through inverse Fourier transform, which is the vibration velocity of the artifacts acting in the casket.

[0026] Example 6: Case Analysis: S1. Basic information on the soil layers at the test site is shown in the table below: Table 2.1 Basic information on soil layers at the test site:

[0027] S2. Rotary drilling piles and steel pipe piles were selected as test objects. Based on the site conditions, the distance between the vibration sources of the two working condition measuring points was determined to be between approximately 5.00 meters and 30.00 meters. Then, measuring points were arranged at five-meter intervals, with three monitoring points at each measuring point. The three-dimensional vibration signals of each monitoring point were collected and processed. The data are shown in the table below: Table 2.12 Average values ​​of PGV under various operating conditions:

[0028] S3. Use finite element software to build a soil model. Then, determine the vibration loads from the two working conditions tested above using the reverse calibration method and simplify them into surface loads, which are then input into the model. Run the model to obtain the final engineering input load. For the rotary drilling pile working condition, refer to the vibration measurement time history curve. Figure 3 .

[0029] S4. Based on the construction drawings of the main museum building, the load-bearing components of the main structure were modeled using finite element analysis software, and then assembled to obtain the main building model. Since the impact of construction vibrations on the building is limited to the elastic limit, the material properties of this model were set to elastic. The load-bearing structural components used C30 concrete, with a material density set to 2.50 × 10³. The elastic modulus is Poisson's ratio is Regarding constraint settings, triaxial rigid fixed-end constraints are set at the bottom of each frame structural column in the model, and the analysis step is set to dynamic explicit analysis.

[0030] S5. Modal analysis shows that the modeling is reasonable and the next step is to proceed with the next step.

[0031] S6. Input the engineering loads to the bottom of the model, set output points at the center of each floor slab or typical locations in the model, and extract these points. The acceleration time history responses in three directions transform the output time domain of each floor into the corresponding output frequency domain using a Fast Fourier Transform, which is then used as the equivalent input frequency domain for each floor-artifact storage cabinet-casket system. See the vertical and horizontal velocity time histories at the F1 output point. Figure 4 .

[0032] S6. Set up measuring points on the ground, in the case, and in the artifact storage cabinet respectively. Apply a controllable excitation signal to the system through a vibrator, and simultaneously collect the excitation force signal. The response signals of the case and the artifact storage cabinet And calculate the frequency response functions of both, such as Figure 5 As shown.

[0033] S7. The input frequency domain of each floor-artifact storage cabinet-casket system is multiplied by the frequency response function of the floor-artifact storage cabinet-casket system to obtain the output frequency domain of each floor-artifact storage cabinet-casket system. The output frequency domain of each floor-artifact storage cabinet-casket system is then transformed into the output time domain of each floor-artifact storage cabinet-casket system (i.e., the vibration velocity of the artifacts acting within the caskets) through inverse Fourier transform, such as... Figure 6 As shown.

Claims

1. A method for evaluating the full-path engineering vibration response of movable cultural relics in museum collections, characterized by: Includes the following steps: Step 1. Simulation of vibration sources during engineering construction; Step 2. Simulate the dynamic response of the museum structure under the vibration source during construction; Step 3. Frequency response function test of the artifact storage cabinet and case; Step 4. Calculate the dynamic response of the museum-artifact storage cabinet-casket system.

2. The method for evaluating the whole-path engineering vibration response of movable cultural relics in a museum collection as described in claim 1, characterized in that, Step 1 includes the following specific steps: Step 11. Determine soil layer information: Obtain the basic parameters of the soil layers at the test site based on the project's geological survey report; Step 12. Determine working condition information: Based on the construction plan, determine the required simulated engineering construction conditions and vibration source distance; Step 13. Measurement point arrangement: With the vibration source as the center, arrange a measurement point every 5 meters; Step 14. Data Acquisition and Processing: Conduct simulated vibration tests under corresponding engineering conditions at the test site. Convert the acquired signals into digital signals using a data acquisition instrument. Then, process the signals through windowing, correction, smoothing, filtering, and truncation to obtain preprocessed digital signals. Step 15. Establishment of dynamic finite element model of soil: Establish a dynamic finite element model of soil based on the geological survey report of the test site. Apply viscoelastic artificial boundary at the boundary of the model. Set spring and damping elements in the normal and tangential directions of the boundary nodes of the model to simulate the effect of the infinite domain on the computational domain. Consider the spring stiffness and damping coefficient of a single point. Calculate the damping ratio of the soil layer by Rayleigh damping. Step 16. Determine the engineering load using the reverse calibration method, as shown in the following formula: ； In the formula, —Equivalent input load; —Equivalent coefficient; —Equivalent mass, the mass unit within the model is ; —Equivalent acceleration; The obtained vibration load is simplified into a surface load form and input into the soil dynamic finite element model, with pre-set... The value is 1, The equivalent input load of the measured value is input into the model, the data of each measuring point is compared with the model data, and the average value of the ratio of each point is taken as the average value. Values ​​are determined based on The equivalent input load is calculated by taking the values.

3. The method for evaluating the full-path engineering vibration response of movable cultural relics in a museum collection as described in claim 1, characterized in that, Step 2 includes the following specific steps: Step 21. Geometric model construction of the museum's dynamic finite element model structure: Based on the museum's architectural drawings, establish the geometric model of the structure in the finite element preprocessing software; Step 22. Simplification of the structural geometric model: Based on the principles of structural mechanics, one-dimensional components such as beams and columns are abstracted as their centerlines and simulated using beam elements; two-dimensional components such as floor slabs and shear walls are abstracted as their surfaces and simulated using shell elements. Irregularly shaped components are decomposed into combinations of regular geometric shapes; based on the assessment of the significant impact on the overall structural stiffness and low-order modes, decorative holes, micro-bevels, and geometric details such as moldings are removed; after simplification, the key inertial parameters of the model are verified, and the error between the total mass and the design value should be less than [a certain value]. The deviation between the center of gravity position and the design value should be controlled within... Overall dimensions of the model The error in all moments of inertia, including the moment of inertia about the center of gravity, is less than [a certain value]. ; Step 23. Determine the material type: Based on the design drawings, determine the materials for each structural component; Step 24. Define basic linear elastic parameters: Based on the "Code for Design of Concrete Structures" and the "Standard for Design of Steel Structures", assign an elastic modulus to each material. Poisson's ratio and mass density ; Step 25. Define the structural damping ratio: Using the Rayleigh damping model, the damping ratio is... Based on the "Code for Seismic Design of Buildings" and experience with similar structures, the following is adopted: Rayleigh damping coefficient and Calculated using the following formula: ； in, ω is the damping ratio of the i-th mode; α is the mass proportional damping coefficient; β is the stiffness proportional damping coefficient; i Let be the i-th natural angular frequency, derived from the first two natural frequencies. Determine that the damping ratio is exactly equal to the damping ratio at these two frequencies. ; Step 26. Determine the element type: Beams and columns: use 3D beam elements that consider shear deformation; Floor slabs, shear walls, and roofs: use shell elements; Solid parts: use solid elements; Step 27. Define and assign section properties: Define the actual cross-sectional shape and size for beams and columns; define the thickness for shell elements; and assign the defined section properties to the corresponding geometric components. Step 28. Mesh Generation and Control: Mesh generation adopts a strategy of primarily using structured meshes supplemented by free meshes; the convergent mesh size is determined through system mesh sensitivity analysis: after two consecutive mesh refinements, the first... The change in natural frequency is less than As a convergence criterion, when generating the final mesh, it is necessary to strictly check the element aspect ratio and Jacobian ratio, and optimize the mesh layout while ensuring accuracy, so as to control the scale of the total degrees of freedom and ensure the computational feasibility of subsequent large-scale dynamic time history analysis. Step 29. Define boundary conditions: Define fixed, elastic, or seismic isolation bearings according to the geological survey report and foundation design, and correctly simulate the connection between structural components; Step 210. Perform modal analysis to verify the rationality of the modeling: If the modal analysis results deviate from the empirical or measured values ​​by more than 10%, the material parameters, connection conditions, and mesh quality need to be checked again until the dynamic characteristics of the model are confirmed to be reasonable. Step 211. Load Input: Simplify the input loads obtained from the vibration source of the simulated engineering construction into surface loads and input them to the bottom of the model; Step 212. Structural Dynamic Time History Analysis and Data Processing: Set up the analysis steps and run the model for finite element analysis. Set output points at the center of each floor slab or typical locations in the model, and extract these points. The acceleration time history response in three directions transforms the output time domain of each floor into the corresponding output frequency domain through fast Fourier transform, and this frequency domain is equivalent to the input frequency domain of each floor-artifact storage cabinet-case system.

4. The method for evaluating the full-path engineering vibration response of movable cultural relics in a museum collection as described in claim 1, characterized in that, Step 3 includes the following specific steps: Step 31. Data Acquisition: Set up measuring points on the ground, in the case, and in the artifact storage cabinet. Apply a controllable excitation signal to the system using a vibrator, and simultaneously acquire the excitation force signal. The response signals of the case and the artifact storage cabinet ; Step 32 calculates the frequency response function, as shown in the following formula: ； For a response signal Perform Fourier transform to obtain Its self-power spectrum Approximately Conjugate with The average of the products is: ; For two signals Input and Output, its cross-power spectrum It is the spectrum of the input signal. With the output signal spectrum conjugate The average of the products, i.e. ; pass Calculate the frequency response functions of the casket and the artifact storage cabinet respectively. ; Step 33. Establish the frequency response function of the floor-artifact storage cabinet-casket system: Use the product of the frequency response functions of the casket and the artifact storage cabinet to represent the equivalent frequency response function of the floor-artifact storage cabinet-casket system, i.e. .

5. The method for evaluating the full-path engineering vibration response of movable cultural relics in a museum collection as described in claim 1, characterized in that, Step 4 includes the following specific steps: Step 41. Calculate the output frequency domain of the floor-artifact storage cabinet-casket system: Multiply the input frequency domain of the floor-artifact storage cabinet-casket system with the frequency response function of the floor-artifact storage cabinet-casket system to obtain the output frequency domain of the floor-artifact storage cabinet-casket system; Step 42. Calculate the output time domain of the floor-artifact storage cabinet-casket system: Transform the output frequency domain of the floor-artifact storage cabinet-casket system into the output time domain of the floor-artifact storage cabinet-casket system through inverse Fourier transform, which is the vibration velocity of the artifacts acting in the casket.

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