Same-layer cylinder batch axial force detection method and system based on vibration response

Abstract

The invention discloses a same-layer cylinder batch axial force detection method and system based on vibration response. The method comprises the steps that common parameters and differential parameters of same-layer components are determined; selecting a reference component and acquiring axial force data of the reference component by adopting a standard detection means; synchronously collecting vibration response data of the same layer of components under the same environment excitation, selecting a response ratio type according to a detection scene, and calculating a response ratio of a target component to a reference component; deriving an incidence relation between the response ratio and the axial force ratio based on a dynamic balance equation, and calculating the axial force ratio of each target component in batches; the axial force values of all the other target components on the same layer are calculated in a batch back-stepping mode by combining the axial force ratio with the axial force value of the reference component; according to the method, lossless and batch detection of the axial force of the same-layer column can be realized, the scene adaptability and the operation convenience of the technology are improved, and meanwhile, the detection efficiency is remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of engineering construction safety assessment, and in particular to a method and system for batch axial force detection of same-story columns based on vibration response. Background Technology

[0002] In the fields of structural health monitoring and safety assessment of buildings in service, columns, as core vertical load-bearing components, directly reflect the rationality of the structural stress on that floor through their axial force state. Therefore, axial force testing of columns on the same floor is a crucial step in structural performance evaluation. Currently, column axial force testing mainly relies on the following existing technologies, each of which has significant limitations in practical applications: I. Traditional Contact Damage Detection Technology: This type of technology, with the borehole stress release method, is the mainstream micro-destructive technique for stress testing of load-bearing components in existing buildings. The operation involves first attaching strain gauges to stress measurement points on the component surface and recording the initial state. Then, using specialized equipment, holes of a certain depth and diameter are drilled, releasing stress and causing strain changes in the area surrounding the holes. The released strain data is collected using strain gauges, and combined with the stress-strain correlation theory in elasticity and the material properties of the component, the internal stress value of the component is calculated. The core drawback of this technology is its low detection efficiency. It requires grinding, attaching, and loading operations column by column. For floors containing multiple columns, the overall detection cycle is long, making it difficult to meet the timeliness requirements for rapid assessment of in-service buildings and posing a risk of structural damage.

[0003] II. Existing vibration detection methods: Although they are non-destructive testing methods, they mostly rely on hammer excitation to apply additional loads, which can easily disturb the structure. They also require the extraction of complex parameters such as multiple vibration modes and eigenvalues. The calculation process involves modal analysis, which has a high threshold for on-site operation and is difficult to adapt to the needs of batch testing in engineering projects. For example, the following solutions, namely Xiangtan University. Frequency method for axial force identification of rigid rods with corrected boundary coefficients: 202510031930.1 [P]. 2025-10-10; Tongji University. An absolute axial force testing method for rods: 201010177384.6 [P]. 2015-03-04; The above patents are limited to rigid rods (such as bridge hangers) and are for axial force identification of single components, without batch testing design. Other existing technologies, such as those from Shenzhen Urban Public Safety Technology Research Institute Co., Ltd., Urban Safety Development Technology Research Institute (Shenzhen). Axial Force Detection Method, Device, Equipment and Storage Medium for Column Groups: 202410356237.7 [P]. 2024-06-04, determine the axial force calculation formula based on the natural frequencies obtained after exciting different categories of classified columns in the column group to be tested, and perform axial force detection according to this formula. All of the above methods rely on vibration sensors to collect data, identify frequencies using complex algorithms such as peak power analysis and power spectrum analysis, have high requirements for signal quality, and require calculation of characteristic parameters, including frequency, displacement mode shape, or strain mode shape. They also require high levels of operator expertise and equipment precision. Therefore, there is an urgent need for an engineering-grade axial force measurement method that is easy to operate, achieves a transformation from "complex tooling" to "lightweight deployment," significantly reduces the threshold for engineering implementation, and improves the efficiency of axial force calculation. Summary of the Invention

[0004] The purpose of this invention is to provide a method for batch axial force testing of columns on the same floor based on vibration response. By deriving the correlation between the vibration response ratio and the axial force ratio between each column on the same floor and the reference column, this invention provides a non-destructive, batch axial force testing method for columns on the same floor of building structures and solves the aforementioned technical problems pointed out in the prior art.

[0005] This invention provides a method for batch axial force detection of same-story columns based on vibration response, comprising the following steps: Determine the common and differential parameters of the same-floor components (the above components refer to columns or pillars); Select a benchmark component and measure its axial force value; use standard testing methods to obtain its axial force data. Vibration response data of components in the same layer under the same environmental excitation are collected simultaneously. The response ratio type is selected according to the detection scenario, and the response ratio of the target component and the reference component is calculated. R i ; The response ratio is derived based on the dynamic equilibrium equation. R iThe correlation between the axial force ratio and the axial force ratio was established, and the axial force ratio of each target component was calculated in batches. The axial force values ​​of the remaining target components in the same layer are calculated by combining the axial force ratio with the axial force value of the reference component.

[0006] Preferably, determining the common parameters and differential parameters of components in the same layer includes: The uniform material strength of the columns on this floor can be obtained through testing, design data, or acceptance data. f c ; Calculate the moment of inertia of the cross section based on its dimensions. I and cross-sectional area A .

[0007] The common parameters include: component material strength. f c The differentiated parameters include: cross-sectional moment of inertia and cross-sectional area; that is, it should be noted that the cross-sectional moment of inertia and cross-sectional area of ​​a component depend on the cross-sectional dimensions. Preferably, the step of selecting a reference component and measuring its axial force value includes: Select a component with a moderate cross-sectional size and no obvious damage in the same layer as the reference component; Axial force data of the reference component (i.e., the reference column) are obtained by non-destructive or minimal-destructive testing methods, and the measured results of the axial force data of the reference component are cross-validated by at least two methods.

[0008] Preferably, the synchronous acquisition of vibration response data of components in the same layer under the same environmental excitation includes: Sensors are deployed at designated locations on each component, with the sensor location being the midpoint of the component's height. The sensor sampling frequency and acquisition duration meet the requirement of covering the first-order natural frequency. When it is not possible to collect data from all components simultaneously, a batch collection method is adopted, ensuring that there is at least one identical component in each batch as a reference.

[0009] Preferably, the step of selecting the response ratio type according to the detection scenario includes: Select the ratio of effective acceleration values, effective velocity values, and effective displacement values ​​based on the detection environment; If the current environment is a high-frequency interference environment, then the ratio of the effective value of acceleration is selected as the response ratio. If the current environment is a low-frequency interference environment, then the ratio of the effective velocity value is selected as the response ratio. If the current environment is a large-amplitude vibration environment, then the ratio of the effective displacement value is selected as the response ratio.

[0010] Preferably, the derivation of the response ratio based on the dynamic equilibrium equation... Ri The relationship between the axial force ratio and the axial force ratio is established, and the axial force ratio of each target component is calculated in batches, including: Based on the dynamic equilibrium equations, the expressions for the response ratio and axial force ratio are derived as follows: No. i The expression for the ratio of axial force between the target component and the reference component is:

[0011] in, C 1. C Both 2 are constants; N ref The reference column axial force; R i The response ratio; I i For the first i Moment of inertia of the cross section of the root column; I ref The moment of inertia of the cross section of the reference column; A i For the first i The cross-sectional area of ​​the root column; A ref The cross-sectional area of ​​the reference column; f c For the strength of the component material; By combining the axial force ratio with the axial force value of the reference component, the axial force values ​​of the remaining target components on the same floor are calculated in batches. In other words, the axial force of each column on the same floor is calculated using the axial force ratio relationship. N i : .

[0012] Preferably, it also includes a correction to the axial force ratio expression when the target column to be detected is a target-fitting component, including... When the cross-sectional dimensions of components in the same layer are consistent, the moment of inertia of the cross section in the axial force ratio relationship expression is simplified by reducing the number of parameters to be input.

[0013] Preferably, when the cross-sectional dimensions of members in the same floor are consistent, the expression for the axial force ratio simplifies to: ; in, C 1. C Both 2 are constants; N ref The axial force of the reference component; R i The response ratio; A i For the first iThe cross-sectional area of ​​the target component; A ref The cross-sectional area of ​​the reference component is given. A i = A ref ; f c The strength of the component material.

[0014] Preferably, a reference component is selected and its axial force value is measured. When the axial compression ratio of the reference component is ≤0.5, its axial force value is measured using the drilling stress relief method or the electromagnetic induction method. N ref ; When synchronously collecting vibration response data of components in the same layer under the same environmental excitation, the process also includes: setting the sensor to be deployed at 1 / 2 height of the current component, setting the sampling frequency to ≥50Hz, and setting the collection duration to ≥2 hours.

[0015] Compared with the prior art, the embodiments of the present invention have at least the following technical advantages: Analysis of the above-mentioned method for batch axial force detection of columns in the same floor based on vibration response provided by the present invention shows that, in specific applications, this method first determines the common and differential parameters of the columns in the same floor. The common parameters include material strength, while the differential parameters include the moment of inertia and cross-sectional area. At the same time, a reference column is selected and its axial force is measured using standard methods. Subsequently, the vibration response of the columns in the same floor under the same environmental excitation is collected, and the response ratio is flexibly calculated according to the actual detection scenario. The effective values ​​of acceleration, velocity, and displacement can be selected. Finally, based on the correlation between the response ratio and the axial force ratio derived from the dynamic equilibrium equation, the axial force ratio of each column in the same floor is calculated in batches, and then the axial force value of the remaining columns is calculated by combining the axial force of the reference column.

[0016] Analysis of the above steps shows that the vibration response-based batch axial force detection method for columns in the same floor provided by this invention is time-consuming and labor-intensive because traditional column axial force measurement often requires testing each column individually. However, this method only requires accurate axial force measurement of one column, while the others are tested through environmental vibration. Synchronous acquisition ensures consistent excitation, enabling rapid batch identification.

[0017] The method for batch axial force testing of same-story columns based on vibration response provided in this invention establishes a direct mechanical correlation between "axial force - effective stiffness - vibration response" based on the derivation of dynamic equilibrium equations, eliminating errors caused by empirical coefficient fitting. This scheme reduces the impact of environmental interference and parameter errors by "compensating for common errors with response ratios," and the testing accuracy meets engineering testing standards. For columns on the same floor with similar material properties, height, and boundary conditions, differing only in axial force and section moment of inertia, the axial force of other columns can be derived through calibration with a reference column.

[0018] In summary, the vibration response-based batch axial force detection method for same-layer columns provided by this invention has stronger anti-interference capabilities, the sensor is lightweight and easy to deploy, the number of sensors is small, and ordinary personnel can operate it after simple training. It overcomes the problem of complex operation of traditional technical methods by eliminating the need for complex signal recognition. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the main process of a batch axial force detection method for same-layer columns based on vibration response provided in Embodiment 1 of the present invention; Figure 2 This is a diagram showing the arrangement of field test sensors in a method for batch axial force detection of same-story columns based on vibration response. Figure 3 This is a schematic diagram of a case study in a method for batch axial force detection of same-layer columns based on vibration response; Figure 4 This is a schematic diagram of a batch axial force detection system for same-layer columns based on vibration response, provided in Embodiment 2 of the present invention.

[0020] Labels: Parameter setting module 10; Reference component detection module 20; Calculation processing module 30; Association processing module 40; Back calculation module 50. Detailed Implementation

[0021] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] The present invention will now be described in further detail with reference to specific embodiments and accompanying drawings.

[0023] Example 1 like Figure 1 As shown, Embodiment 1 of the present invention provides a method for batch axial force detection of same-layer columns based on vibration response, including the following operation steps: S10. Determine the common parameters and differential parameters of the same-floor components (the above components refer to columns or pillars); S20. Select a reference component and measure its axial force value, and obtain its axial force data using standard testing methods; S30. Simultaneously acquire vibration response data of components in the same layer under the same environmental excitation, select the response ratio type according to the detection scenario, and calculate the response ratio between the target component and the reference component. R i ; S40. Deriving the response ratio based on the dynamic equilibrium equation. R i The correlation between the axial force ratio and the axial force ratio was established, and the axial force ratio of each target component was calculated in batches. S50. The axial force values ​​of the remaining target components in the same layer are calculated in batches by combining the axial force ratio with the axial force value of the reference component.

[0024] It should be noted that this method first determines the common and differential parameters of columns in the same floor. The common parameters include material strength, while the differential parameters include the moment of inertia and cross-sectional area. At the same time, a reference column is selected and its axial force is measured using standard methods. Subsequently, the acceleration or velocity response of the same-layer column under the same environmental excitation is collected, and the response ratio is flexibly calculated according to the actual detection scenario. The effective values ​​of displacement, acceleration, and velocity can be selected. Finally, based on the correlation between the response ratio and the axial force ratio derived from the dynamic equilibrium equation, the axial force ratio of each column in the same floor is calculated in batches, and then the axial force value of the remaining columns is calculated in combination with the axial force of the reference column.

[0025] Analysis of the above steps reveals that Embodiment 1 of the present invention provides a method for batch axial force testing of columns on the same floor based on vibration response. Addressing the engineering needs of axial force testing of columns on the same floor in in-service buildings, this method simplifies the application of mechanical theory and optimizes the testing process, specifically addressing the shortcomings of traditional technologies in terms of efficiency, cost, damage control, and operational barriers. It provides a practical solution for batch, efficient, and non-destructive column axial force testing, with the following specific beneficial effects: On the one hand, it protects structural integrity without the need for artificial excitation: the entire process utilizes environmental excitation, eliminating the need for additional loads such as hammering, and the sensor deployment does not require damage to the column's protective layer, completely solving the problem of structural damage caused by traditional damage methods, making it particularly suitable for buildings already in use; based on the derivation of the dynamic equilibrium equation, a direct mechanical relationship between "axial force - effective stiffness - vibration response" is established, eliminating errors caused by empirical coefficient fitting; the above scheme reduces the impact of environmental interference and parameter errors by "response ratio offsetting common errors", and the detection accuracy can meet engineering testing standards.

[0026] On the other hand, batch testing significantly improves efficiency: only one reference column axial force needs to be measured to calculate the axial force of all columns in the floor through the response ratio; in the same cross-section scenario, the simplified formula further reduces parameter input; by using the common parameters of columns in the same floor to offset common variables, there is no need to repeatedly test or model each column, and the axial force testing of multiple columns in the same floor can be completed simultaneously, greatly shortening the testing cycle and making it more suitable for batch testing scenarios of in-service buildings.

[0027] On the other hand, the operation process is simplified and the technical threshold is lowered: the embodiment of the present invention simplifies the detection process to "parameter measurement → response acquisition → formula calculation", which does not require mastery of advanced mechanical theory and professional software. The parameters are easy to obtain and the on-site personnel can operate after simple training, thus lowering the technical application threshold.

[0028] Preferably, determining the common parameters and differential parameters of components in the same layer includes: Measure the height of components on the same floor, and obtain the strength of the component materials through testing or design data and acceptance data. f c ; Calculate the moment of inertia of the cross section based on its dimensions. I Cross-sectional area A .

[0029] The common parameters include: component material strength. f c ; The differentiated parameters include: moment of inertia of the cross section. I Cross-sectional area A It should be noted that the moment of inertia and cross-sectional area of ​​a component depend on its cross-sectional dimensions. (Cross-sectional area) A It can be the cross-sectional area A i or cross-sectional area A ref ;in, A i It is the first i The cross-sectional area of ​​the root column, A ref This refers to the cross-sectional area of ​​the reference column. It should be noted that the specific plan is as follows: S101. Measure common parameters: Select the floor to be tested and obtain the uniform material strength of the columns on that floor through testing or design data and acceptance data; S102. Measure differential parameters: For each column on the current floor (denoted as the...),... i Root column, i =1,2,..., n, n (This represents the total number of columns on this floor), measure their cross-sectional dimensions (for rectangular columns, measure the width). b i ,high h i Measure the diameter of a cylindrical cylinder d i ), calculate the moment of inertia of the cross section I i (rectangular column) , cylindrical ), column cross-sectional area A i .

[0030] Preferably, the step of selecting a reference component and measuring its axial force value includes: Select a component with a moderate cross-sectional size and no obvious damage in the same layer as the reference component (at this time) i (Ref is the root member of the ref term). The appropriate cross-sectional size refers to the classification and arrangement of cross-sectional sizes among columns in the same layer (e.g., arrangement of 1-50 columns). Columns arranged between number 20 and 30 with uniform load-bearing capacity are used as the benchmark members. Members without obvious damage can be selected and determined by manual experience, which will not be elaborated further.

[0031] Axial force data of the reference component (i.e., the reference column) are obtained by non-destructive or minimal-destructive testing methods, and the measured results of the axial force data of the reference component are cross-validated by at least two methods.

[0032] It should be noted that the above steps are performed as follows: the axial force of the reference column is measured using standard non-destructive / minor destructive methods (such as borehole stress relief method or electromagnetic induction method). N ref And cross-validation was performed using two methods.

[0033] Preferably, the synchronous acquisition of vibration response data of components in the same layer under the same environmental excitation includes: Sensors are deployed at designated locations on each component, with the sensor location being the midpoint of the component's height. The sensor sampling frequency and acquisition duration meet the requirement of covering the first-order natural frequency. When it is not possible to collect data from all components simultaneously, a batch collection method should be adopted, ensuring that at least one identical component is used as a reference between each batch. It should be noted that the vibration response data collected in the above steps refer to the vibration signal data in the weak axis direction of the horizontal cross-section of the component.

[0034] Preferably, the step of selecting the response ratio type according to the detection scenario includes: Select the ratio of effective displacement values, effective velocity values, and effective acceleration values ​​based on the detection environment; If the current environment is a high-frequency interference environment, then the ratio of the effective value of acceleration is selected as the response ratio. If the current environment is a low-frequency interference environment, then the ratio of the effective velocity value is selected as the response ratio. If the current environment is a large-amplitude vibration condition, then the ratio of the effective displacement value is selected as the response ratio.

[0035] It should be noted that if the response ratio R i Ratio of effective acceleration values . No. i Effective value of acceleration of the root target component , T Represents the duration of signal acquisition. This is the preprocessed acceleration time-domain signal; the discretized acquired data can be approximated by summation and integration. in, N The total number of data points collected. For the first j The acceleration values ​​of each discrete sampling point were calculated, and the response ratio of each target column to the reference column was also calculated.

[0036] It should be noted that if the response ratio R i To calculate the ratio of effective speed values, the following method is used: The speed signal is directly measured using a sensor. Alternatively, the acceleration signal can be integrated after zero-drift correction, i.e. ;No. i Calculation of the effective value of the velocity of the root target component: Discretized data acquisition can be approximated by summation and integration. , For the first j The velocity value of each discrete sampling point; the definition of the response ratio: .

[0037] It should be noted that if the response ratio R i The effective value of displacement ( The ratio (adapted to low-frequency interference scenarios) is calculated as follows: displacement is directly measured using a sensor. Alternatively, the velocity signal can be integrated after zero-drift correction, i.e.: If obtained indirectly from the acceleration signal, the velocity must be integrated first, and then the displacement must be integrated again, i.e. ;No. i Calculation of the effective displacement value of the target component: When discretizing the acquired data, approximate integration is performed through summation: , For the first j Displacement values ​​of discrete sampling points; Response ratio definition: .

[0038] Preferably, the derivation of the response ratio based on the dynamic equilibrium equation... R i The relationship between the axial force ratio and the axial force ratio is established, and the axial force ratio of each target component is calculated in batches, including: Based on the dynamic equilibrium equations, the expressions for the response ratio and axial force ratio are derived as follows: No. i The expression for the ratio of axial force between the target component and the reference component is: ; in, C 1.C Both 2 are constants; N ref The reference column axial force; R i The response ratio; I i For the first i Moment of inertia of the cross section of the root column; I ref The moment of inertia of the cross section of the reference column; A i For the first i The cross-sectional area of ​​the root column; A ref The cross-sectional area of ​​the reference column; f c For the strength of the component material; The axial force values ​​of the remaining target components on the same floor are calculated by batch reverse calculation using the expression and the axial force value of the reference component. N i ,Right now .

[0039] Preferably, it also includes a correction to the axial force ratio expression when the target column to be detected is a target-fitting component, including: When the cross-sectional dimensions of components in the same layer are consistent, the moment of inertia of the cross section in the axial force ratio relationship expression is simplified by reducing the number of parameters to be input.

[0040] Preferably, when the cross-sectional dimensions of members in the same floor are consistent, the expression for the axial force ratio simplifies to:

[0041] in, C 1. C Both 2 are constants; N ref The axial force of the reference component; R i The response ratio; A i For the first i The cross-sectional area of ​​the target component; A ref The cross-sectional area of ​​the reference component is given. A i = A ref ; f c The strength of the component material.

[0042] Preferably, a reference component is selected and its axial force value is measured using either the drilling stress relief method or the electromagnetic induction method. Nref ; When synchronously collecting vibration response data of components in the same layer under the same environmental excitation, the process also includes: setting the sensor to be deployed at 1 / 2 height of the current component, setting the sampling frequency to ≥50Hz, and setting the collection duration to ≥2 hours.

[0043] The following is a specific application case of the vibration response-based batch axial force testing method for same-story columns (for the detailed process of the case, please refer to...). Figure 2 For a schematic diagram of the sensor layout for field testing, please refer to [link / reference]. Figure 3 ): S1. Determine the common and differential parameters of columns on the same floor; S101. Measurement of common parameters: Select the floor to be tested, and obtain the uniform material strength of the columns on that floor through core sampling or material certificate testing. f c ; S102. Measure the differential parameters: for each column on this floor (denoted as the first column). i Root column, i =1,2,..., n, n (This represents the total number of columns on this floor), measure their cross-sectional dimensions (for rectangular columns, measure the width). b i ,high h i Measure the diameter of a cylindrical cylinder d i ), calculate the moment of inertia of the cross section I i (rectangular column) , cylindrical ), column cross-sectional area A i .

[0044] S2. Select a reference column and measure its axial force. S201. Reference Column Selection: Select a column with moderate cross-sectional dimensions and no obvious damage in this floor as the reference column (at this time...). i Denoteed as ref, i.e. the ref-th root column), ensuring that the axial compression ratio of the reference column is ≤0.5 (which conforms to the stress state of most in-service columns); S202. Measurement of Axial Force in Reference Column: The axial force of the reference column shall be measured using standard non-destructive / minimally destructive methods (such as borehole stress relief method or electromagnetic induction method). N ref And cross-validation was performed using two methods.

[0045] S3. Simultaneously acquire vibration response under environmental excitation of the same-floor column. S301. Sensor deployment: Install the same type of sensor at 1 / 2 height of each column (where the bending moment is the largest and the response is the most significant), with a frequency response of 0.1-100Hz, and calibrate it in advance using a vibration table; S302. Environmental Excitation Data Acquisition: During nighttime periods without construction or traffic interference (environmental noise ≤50dB), synchronously acquire the horizontal vibration response signals of all sensors, with a sampling frequency ≥50Hz and an acquisition duration ≥2 hours, ensuring data coverage of the first-order natural frequency resonance region. When it is not possible to acquire data simultaneously for all components, batch testing can be selected, ensuring that each batch contains at least one identical component under test.

[0046] S303. Calculate response parameters and response ratios: Based on the detection environment and accuracy requirements, select any one of the following types of response parameters to calculate the response ratio. All parameters are based on vibration signals collected in the same batch: RMS acceleration ( Ratio (for high-frequency interference environments): The acquired acceleration signal was low-pass filtered at 50Hz. i Effective value of the acceleration of the root column , T Represents the duration of signal acquisition. This is the preprocessed acceleration time-domain signal; the discretized acquired data can be approximated by summation and integration. in, N The total number of data points collected. For the first j The acceleration values ​​at each discrete sampling point are calculated, and the response ratio of each column to the reference column is also calculated. .

[0047] Effective value of speed ( Ratio (for low-frequency interference scenarios): Speed ​​signal acquisition: Direct measurement using sensors Alternatively, the acceleration signal can be integrated after zero-drift correction, i.e. ;No. i Calculation of the effective value of the velocity of the root column: Discretized data acquisition can be approximated by summation and integration. , For the first j The velocity values ​​of each discrete sampling point; Response ratio definition: .

[0048] Effective value of displacement ( Ratio (for low-frequency interference scenarios): Displacement is measured directly using sensors. Alternatively, the velocity signal can be integrated after zero-drift correction, i.e.: If obtained indirectly from the acceleration signal, the velocity must be integrated first, and then the displacement must be integrated again, i.e. ;No. i Calculation of the effective value of the displacement of the column: When discretizing the acquired data, approximate integration is performed through summation: , For the first j Displacement values ​​of discrete sampling points; Response ratio definition: .

[0049] S4. Deriving Axial Force Based on Dynamic Equilibrium Equations S401. Establish the relationship between effective stiffness and axial force: The effective stiffness of the column under horizontal vibration in the same floor is: ; in, K i,N For the first i Effective stiffness of the column under axial force K 0,i For the first i Effective stiffness of a column without axial force (fixed-fixed column) Fixed-Free Column , E , L These represent the material elastic modulus and height of the column, respectively; the values ​​are consistent for all columns within the same floor. For the first i Root column lateral stiffness correction factor It depends on the axial compression ratio. μ The axial compression ratio, , N For axial force, A For cross-sectional area, C 1. C 2 is a constant that can be obtained through experiments, numerical simulations, or existing literature to obtain the fitting coefficient.

[0050] S402. Establish the random vibration response under low-frequency excitation: Under environmental excitation, the column response is concentrated at the first natural frequency. The vibration response of the frame column is analyzed using a single-degree-of-freedom system. The equation of motion for the horizontal random vibration of the single-degree-of-freedom system is: ; In the formula: The response to the horizontal displacement at mid-span (stochastic process). For random excitation force, For component damping, m For component quality.

[0051] By using the Fourier transform, the frequency domain is transformed (the independent variable is...). ω (i.e., the external load angular frequency component obtained through Fourier transform), response function Defined as the ratio of the displacement response to the amplitude of the excitation force, the expression is: ; Here i' Used to indicate that the function is a complex number. ω n When the natural frequency of the column is given, and the external load excitation is an environmental excitation with low-frequency characteristics, that is... ,but , ζ Substituting the component damping ratio into the above equation, we obtain the simplified form of the quasi-static frequency response function: ; The simplified physical meaning is that under low-frequency excitation, the system response is close to the static characteristics, and the effects of damping and inertial forces can be ignored, which is consistent with the law that "horizontal force-lateral displacement are linearly related" in the experiment.

[0052] Power spectral density of displacement response With excitation power spectral density The relationship is: ; Substitute the simplified have to: ; The root mean square magnitude (RMS value) of a stationary random process is the square root of the integral of the power spectral density. ; Will Substituting, we get: ; make Then the root mean square amplitude of the displacement response simplifies to: ; S403. Derive the expression for the axial force ratio and the formula for calculating axial force: Relationship between displacement response amplitude ratio and stiffness ratio For the same excitation on the tested component, the root mean square amplitudes of the displacements of the target component and the reference component are respectively: ; Define axial force ratio (The ratio of the axial force of the target column to the axial force of the reference column), the displacement response amplitude ratio is: ; The study found that under stable random excitation in the environment, the relationship between the velocity and acceleration response ratios and the axial force ratio is completely consistent with that of the displacement response ratio.

[0053] The expression for the axial force ratio is obtained by refining the expression:

[0054] Derivation of axial force calculation formula: Substituting the axial force ratio into the axial force ratio relationship expression, we obtain the formula for calculating the axial force of the target column:

[0055] S404. Batch calculation of axial force of columns on the same floor: The measurements from S1 to S3 f c , I i 、I ref 、R i 、N ref 、A i 、A ref 、C 1. C 2. Substitute the values ​​into the above axial force calculation formula to calculate the axial force of all columns on this floor in batches. N i .

[0056] Further optimized technical solutions Response Ratio Selection Guide The response ratio should be selected based on the detection environment, accuracy requirements, and operational complexity, according to the following principles: In typical scenarios (ambient noise ≤50dB, rapid detection): the ratio of effective acceleration values ​​is the simplest to operate and requires no additional signal processing. For low-frequency interference scenarios (noise 50-60dB, including interference from people walking around): Select the velocity RMS ratio for stronger resistance to low-frequency interference; For large-amplitude vibration scenarios: the ratio of effective displacement values ​​is selected. The signal-to-noise ratio is high, it is not easily submerged by noise, and the change can directly reflect the degree of stiffness degradation, which is more sensitive than acceleration and velocity.

[0057] Irregular cross-section adaptation: When the columns on the same floor have irregular cross-sections (such as T-shaped or L-shaped), the moment of inertia of the cross-section is extracted from the BIM model or CAD drawings in step S102. I i This avoids errors from manual calculations.

[0058] Simplified calculation formula when the cross-sectional dimensions are consistent: When the columns of the floors to be tested have uniform cross-sectional dimensions, the cross-sectional area and moment of inertia are equal. Substituting these into the expression for the axial force ratio and eliminating the uniform parameter, we get: Using time-domain amplitude-type response ratio ; The expression for the axial force ratio is obtained by refining the expression:

[0059] This simplified formula only requires input. f c , A i , A ref 、C 1. C 2. Axial force of the reference column N ref Response ratio R i It eliminates the need for repeated calculations of parameters such as cross-sectional dimensions and mass, making it suitable for batch testing scenarios in standardized buildings such as residential buildings and office buildings.

[0060] Example 2 See Figure 4 Accordingly, the present invention provides a batch axial force detection system for same-story columns based on vibration response, comprising: The parameter setting module 10 determines the common parameters and differential parameters of the same-floor components (the above components refer to columns or pillars); The reference component detection module 20 is used to select a reference component and measure its axial force value, and to obtain its axial force data using standard detection methods. The calculation and processing module 30 is used to synchronously acquire vibration response data of components in the same layer under the same environmental excitation, select the response ratio type according to the detection scenario, and calculate the response ratio between the target component and the reference component. R i ; The correlation processing module 40 is used to derive the response ratio based on the dynamic equation. R i The correlation between the axial force ratio and the axial force ratio was established, and the axial force ratio of each target component was calculated in batches. The reverse calculation module 50 is used to combine the axial force ratio with the axial force value of the reference component to calculate the axial force value of each target component in the same layer in batches.

[0061] In summary, this invention establishes the correlation between the vibration response ratio and the axial force ratio between each column and the reference column within the same floor. Addressing the engineering needs of axial force testing of columns within the same floor of in-service buildings, it simplifies the application of mechanical theory and optimizes the testing process. This invention specifically addresses the shortcomings of traditional technologies in terms of efficiency, cost, damage control, and operational barriers, providing a practical solution for batch, efficient, and non-destructive column axial force testing. Its specific beneficial effects are as follows: On the one hand, it protects structural integrity without the need for artificial excitation: the entire process utilizes environmental excitation, eliminating the need for additional loads such as hammering, and the sensor deployment does not require damage to the column's protective layer, completely solving the problem of structural damage caused by traditional damage methods, which is especially suitable for buildings already in use; based on the derivation of the dynamic equilibrium equation, a direct mechanical relationship between "axial force - effective stiffness - vibration response" is established, eliminating errors caused by empirical coefficient fitting; the above scheme reduces the impact of environmental interference and parameter errors by "response ratio offsetting common errors".

[0062] On the other hand, batch testing significantly improves efficiency: only one reference column axial force needs to be measured to calculate the axial force of all columns in the floor through the response ratio; in the same cross-section scenario, the simplified formula further reduces parameter input; by using the common parameters of columns in the same floor to offset common variables, there is no need to repeatedly test or model each column, and the axial force testing of multiple columns in the same floor can be completed simultaneously, greatly shortening the testing cycle and making it more suitable for batch testing scenarios of in-service buildings.

[0063] On the other hand, the operation process is simplified and the technical threshold is lowered: the embodiment of the present invention simplifies the detection process to "parameter measurement - response acquisition - subsequent relational back calculation", which does not require mastery of advanced mechanics theory and professional software. The parameters are easy to obtain and can be operated by on-site personnel after simple training, thus lowering the technical application threshold.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; those skilled in the art can modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for batch axial force detection of same-story columns based on vibration response, characterized in that, include: Determine the common and differential parameters of components on the same floor; Select a benchmark component and measure its axial force value; use standard testing methods to obtain its axial force data. Vibration response data of components in the same layer under the same environmental excitation are collected simultaneously. The response ratio type is selected according to the detection scenario, and the response ratio of the target component and the reference component is calculated. R i ; The response ratio is derived based on the dynamic equilibrium equation. R i The correlation between the axial force ratio and the axial force ratio was established, and the axial force ratio of each target component was calculated in batches. The axial force values ​​of the remaining target components in the same layer are calculated by combining the axial force ratio with the axial force value of the reference component.

2. The method as described in claim 1, characterized in that, The determination of common parameters and differentiated parameters of components in the same layer includes: The strength of the component materials is obtained through testing or design data and acceptance data. f c ; Calculate the moment of inertia of the component based on its cross-sectional dimensions. I and cross-sectional area A ; The common parameters include: material strength. f c ; The differentiated parameters include: moment of inertia of the cross section. I cross-sectional area A。 3. The method as described in claim 1, characterized in that, The selection of a reference component and the actual measurement of its axial force value include: Select a component with a moderate cross-sectional size and no obvious damage in the same layer as the reference component; Axial force data of reference components are obtained using non-destructive or minimal-destructive testing methods. N ref The measured results of the axial force data of the above-mentioned reference components were cross-validated using at least two methods.

4. The method as described in claim 1, characterized in that, The synchronous acquisition of vibration response data of components in the same layer under the same environmental excitation includes: Sensors are deployed at designated locations on each component, with the sensor location being the midpoint of the component's height. The sensor sampling frequency and acquisition duration meet the requirement of covering the first-order natural frequency. When it is not possible to collect data from all components simultaneously, a batch collection method is adopted, ensuring that there is at least one identical component in each batch as a reference.

5. The method as described in claim 4, characterized in that, The selection of response ratio type based on the detection scenario includes: Select the ratio of effective acceleration values, effective velocity values, and effective displacement values ​​based on the detection environment; If the current environment is a high-frequency interference environment, then the ratio of the effective value of acceleration is selected as the response ratio. If the current environment is a low-frequency interference environment, then the ratio of the effective velocity value is selected as the response ratio. If the current environment is a large-amplitude vibration environment, then the ratio of the effective displacement value is selected as the response ratio.

6. The method as described in claim 1, characterized in that, The response ratio is derived based on the dynamic equilibrium equation. R i The relationship between the axial force ratio and the axial force ratio is established, and the axial force ratio of each target component is calculated in batches, including: Based on the dynamic equilibrium equations, the expressions for the response ratio and axial force ratio are derived as follows: No. i The expression for the ratio of axial force between the target component and the reference component is: in, C 1. C Both 2 are constants; N ref The axial force of the reference component; R i The response ratio; I i For the first i Moment of inertia of the cross section of the target component; I ref The moment of inertia of the cross section of the reference member; A i For the first i The cross-sectional area of ​​the target component; A ref The cross-sectional area of ​​the reference component; f c For the strength of the component material; The axial force values ​​of the remaining target components on the same floor are calculated by combining the axial force ratio with the axial force value of the reference component. .

7. The method as described in claim 6, characterized in that, It also includes the correction of the axial force ratio expression when the target column to be detected is a target-fitting component; The correction of the axial force ratio expression is performed when the target component to be detected is a target-fitting component: When the cross-sectional dimensions of components in the same layer are consistent, the moment of inertia of the cross section in the axial force ratio relationship expression is simplified by reducing the number of parameters to be input.

8. The method as described in claim 7, characterized in that, When the cross-sectional dimensions of components in the same layer are consistent, the expression for the axial force ratio simplifies to: ； in, C 1. C Both 2 are constants; N ref The axial force of the reference component; R i The response ratio; A i For the first i The cross-sectional area of ​​the target component; A ref The cross-sectional area of ​​the reference component is given. A i = A ref ; f c The strength of the component material.

9. The method according to claim 1, characterized in that, Select a reference component and measure its axial force value. When the axial compression ratio of the reference component is ≤0.5, use the drilling stress relief method or electromagnetic induction method to measure its axial force value. N ref ; When synchronously collecting vibration response data of components in the same layer under the same environmental excitation, the process also includes: setting the sensor to be deployed at 1 / 2 height of the current component, setting the sampling frequency to ≥50Hz, and setting the collection duration to ≥2 hours.

10. A batch axial force detection system for same-story columns based on vibration response, characterized in that, include: Parameter setting module, benchmark component detection module, calculation processing module, correlation processing module, and back-calculation module; The parameter setting module determines the common parameters and differentiated parameters of components on the same floor; The reference component detection module is used to select a reference component and measure its axial force value, and to obtain its axial force data using standard detection methods; The calculation and processing module is used to synchronously collect vibration response data of components in the same layer under the same environmental excitation, select the response ratio type according to the detection scenario, and calculate the response ratio between the target component and the reference component. R i ; The correlation processing module is used to derive the response ratio based on the dynamic balance equation. R i The correlation between the axial force ratio and the axial force ratio was established, and the axial force ratio of each target component was calculated in batches. The reverse calculation module is used to combine the axial force ratio with the axial force value of the reference component to calculate the axial force value of each target component in the same layer in batches.

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