Bridge damping ratio testing method, system, equipment and program product

Abstract

The invention discloses a bridge damping ratio testing method, system, device and program product, and the method comprises the steps: building a finite element model of a to-be-tested bridge, and carrying out the simulation analysis of the model, and obtaining a dynamic characteristic parameter theoretical result; acquiring bridge structure vibration data under various natural environment excitation; according to a dynamic characteristic parameter theoretical result, performing modal fitting analysis on the environment excitation vibration data to obtain dynamic characteristic parameters of each order vibration mode under various natural environment excitation in different time periods; based on the dynamic characteristic parameters under the natural environment excitation, collecting the structural dynamic response of the excitation vehicle in the continuous excitation process of the to-be-tested bridge, and obtaining the dynamic characteristic parameters under the artificial excitation of each order of vibration mode; according to the theoretical result of the dynamic characteristic parameters of the to-be-tested bridge, modal fitting analysis is conducted on the dynamic characteristic parameters under manual excitation, and the damping ratio of each order of vibration mode of the to-be-tested bridge is obtained. The bridge damping ratio testing method disclosed by the invention has the advantages of small error, high precision and high efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of bridge engineering detection, and in particular to a bridge damping ratio testing method, system, equipment and program product. Background Art

[0002] With the continuous increase in bridge spans, innovations in structural systems, and the application of lightweight and high-strength materials, the damping of long-span bridge structures has been decreasing, further exacerbating the sensitivity of long-span bridges to dynamic loads such as wind, vehicles, and earthquakes. Damping is a parameter that reflects the energy dissipation characteristics of the structural system during vibration. It is an important factor affecting the structural vibration response and seismic response, and a key parameter for dynamic analysis such as wind and earthquake resistance of long-span bridges. Damping has a wide range of connotations and a complex mechanism. It is difficult to have an exact analysis method or static test data as a reference like physical quantities such as the mass and stiffness of the structure, and it is difficult to draw a unified and more practical understanding; at the same time, damping is one of the important factors affecting the dynamic response of the structure. Whether the damping can be correctly estimated directly affects the reliability of the results of the structural dynamic analysis. Therefore, the dual characteristics of the uncertainty and importance of damping have made the research on the damping problem always valued by the vibration engineering community, and it is crucial to reasonably determine the structural damping of long-span bridges.

[0003] Viscous damping ratio is a form of damping in structural engineering. It is widely used because of its clear concept and simple calculation. The vibration response of a bridge is often dominated by a certain order of mode. For example, the vertical vortex-induced vibration occurred on the Humen Bridge, and the main vortex-induced resonance modes were the third, fourth, and fifth vertical orders. Therefore, when calculating the dynamic response of a bridge, the modal damping ratio is generally used to equivalently represent the combined effect of various damping mechanisms. The modal damping ratio represents the damping ratio of the structure when it vibrates according to the nth order mode, reflecting the degree of vibration energy dissipation of the structure under the nth order mode vibration mode.

[0004] The damping test of a structure generally collects the velocity or acceleration parameters of the structure and then makes corresponding changes to obtain the damping value. The excitation method is very important. The excitation methods for testing damping mainly include environmental excitation and forced vibration excitation resonance, sub-resonance, and pulse load.

[0005] The identification of damping ratio using vibration response data under environmental excitation is currently a widely used damping ratio identification method. Natural vibration sources of environmental excitation include earthquakes, ground pulsations, wind vibrations, and waves. Among them, ground pulsations are often used to excite large building structures. They are characterized by a wide frequency band and contain various frequency components, but they are very random and require a long sampling time. However, the actual environment of bridge structures is complex. They are affected by loads such as vehicles, wind, and temperature. They are non-stationary and colored, which is inconsistent with the Gaussian white noise assumption. Under wind loads, bridge structures will produce aerodynamic damping, which changes with the external wind environment, affecting the damping identification results. Moving vehicle loads also change the characteristics of the bridge. The vehicle-bridge coupled vibration causes the bridge vibration signal to be mixed with vehicle vibration information. In addition, the modal damping ratio is nonlinear and related to the amplitude and vibration frequency. The weak environmental vibration response cannot truly reflect the damping condition under large amplitude conditions. The damping ratio of high-order modes is difficult to accurately identify, but long-span bridges are sensitive to high-order wind-induced vibrations.

[0006] The signal of forced vibration excitation is obvious and the data interference is small, but the excitation methods for forced vibration of large structures are limited. It is difficult to apply forced vibration to large-span bridges due to the output force limit of the excitation equipment.

[0007] The existing bridge damping ratio test currently has the following problems: the damping ratio of the environmental excitation test of the large-span bridge has a wide frequency band and a small amplitude, and adjacent frequency bands will overlap, resulting in inaccurate spectrum analysis values; it is very important to test the damping ratio under a resonant state of a certain vibration mode, and there is no other method except forced vibration. Forced vibration excitation of large-span bridges requires large-scale excitation equipment, and there is still the problem of insufficient excitation force, difficulty in exciting high-order vibration modes, and expensive excitation equipment; simply relying on vehicle driving excitation can only excite the vibration-sensitive areas of the vehicle, and other areas are similar to natural excitation.

[0008] Therefore, it is urgent to invent a damping ratio testing method with small error, high precision and high efficiency to accurately test the damping ratio of long-span bridges. Summary of the invention

[0009] In view of this, the embodiments of the present invention provide a bridge damping ratio testing method, system, device and program product, which at least partially solve the problems existing in the prior art.

[0010] Other features and advantages of the present invention will become apparent from the following detailed description, or may be learned in part by practice of the present invention.

[0011] In order to achieve the above purpose, the embodiment of the present invention provides the following technical solutions:

[0012] According to a first aspect of an embodiment of the present invention, a bridge damping ratio testing method is provided, the method comprising:

[0013] For the bridge to be tested, a corresponding bridge structure finite element model is constructed, and the bridge structure finite element model is used to perform structural dynamic simulation analysis to obtain the bridge structure theoretical modal parameter frequency and bridge vibration mode corresponding to the bridge to be tested;

[0014] According to a preset collection period, intermittently collect vibration data of the bridge to be tested under various natural environment excitations and corresponding natural environment parameters to obtain environmental excitation vibration data;

[0015] According to the theoretical modal parameter frequency of the bridge structure and the bridge vibration mode corresponding to the bridge to be tested, the modal fitting analysis and processing is performed on the environmental excitation vibration data to obtain the dynamic characteristic parameters of each order vibration mode of the bridge to be tested under various natural environment excitations;

[0016] Based on the dynamic characteristic parameters under the excitation of the natural environment, the structural dynamic response of the vibration vehicle in the process of continuously exciting the characteristic position of the bridge to be tested by continuously jumping through the test obstacle is collected, and the dynamic characteristic parameters of the bridge to be tested under artificial excitation of each vibration mode are obtained according to the structural dynamic response;

[0017] According to the theoretical modal parameter frequency of the bridge structure and the bridge vibration mode corresponding to the bridge to be tested, the dynamic characteristic parameters under artificial excitation of each vibration mode are subjected to modal fitting analysis to obtain the damping ratio corresponding to each vibration mode of the bridge to be tested.

[0018] Furthermore, the finite element model of the bridge structure is used to perform structural dynamic simulation analysis to obtain the theoretical modal parameter frequency and bridge vibration mode of the bridge structure corresponding to the bridge to be tested, including:

[0019] If the bridge to be tested is a long-span cable-stayed bridge or a long-span suspension bridge, at least the first nine vibration modes of the bridge to be tested are extracted;

[0020] If the bridge to be tested is a long-span beam bridge, at least the first three vibration modes of the bridge to be tested are extracted.

[0021] Furthermore, the natural environment parameters include temperature, wind speed and wind direction;

[0022] The preset collection period includes the highest temperature period and the lowest temperature period in a day.

[0023] Furthermore, the modal fitting analysis process includes an enhanced frequency domain decomposition method and a time domain analysis method.

[0024] Furthermore, based on the dynamic characteristic parameters under natural environment excitation, the structural dynamic response of the vibration vehicle during the continuous vibration of the characteristic position of the bridge to be tested by continuously jumping the vehicle through the test obstacle is collected, and the dynamic characteristic parameters of each order vibration mode of the bridge to be tested under artificial excitation are obtained according to the structural dynamic response, including:

[0025] Using the dynamic characteristic parameters of each vibration mode of the bridge to be tested under various natural environment excitations, the average value of the natural frequency of each vibration mode under all natural environment excitations is calculated;

[0026] According to the driving speed of the exciting vehicle, the obstacle spacing is calculated using the average value of the natural frequency of each vibration mode. The calculation formula is:

[0027] d=v / f

[0028] Where d is the obstacle distance, v is the speed of the exciting vehicle, and f is the average natural frequency of each vibration mode under all natural environment excitations;

[0029] According to the obstacle spacing, at least two groups of test obstacles are set on the bridge to be tested, and an exciting vehicle is used to continuously pass through the test obstacles at a uniform speed at a preset speed, and the characteristic position of the bridge to be tested is continuously excited at a preset frequency by continuously jumping the vehicle.

[0030] Furthermore, based on the dynamic characteristic parameters under the excitation of the natural environment, the structural dynamic response of the vibration vehicle during the continuous vibration of the characteristic position of the bridge to be tested by continuously jumping through the test obstacle is collected, and the dynamic characteristic parameters of the bridge to be tested under artificial excitation of each vibration mode are obtained according to the structural dynamic response, which also includes:

[0031] Collect the structural dynamic response from before the exciting vehicle goes on the bridge to when the amplitude at the exciting position recovers;

[0032] By using the structural dynamic response, the dynamic characteristic parameters of the bridge to be tested under artificial excitation of each vibration mode under excitation and residual vibration are obtained.

[0033] Further, according to the obstacle spacing, at least two groups of test obstacles are set on the bridge to be tested, including:

[0034] According to the theoretical results of dynamic characteristic parameters obtained through structural dynamic simulation analysis of the bridge to be tested, the area with the largest bending degree of the bridge to be tested is taken as the excitation area;

[0035] Arranging at least two groups of test obstacles in the excitation area;

[0036] Arrange vibration pickups for dynamic characteristic testing corresponding to the test obstacles on one side of each test obstacle;

[0037] The energy of each vibration mode is adjusted by using the weight of the exciting vehicle, the height of the obstacle, and the number of obstacles in the characteristic area during artificial excitation.

[0038] According to a second aspect of an embodiment of the present invention, a bridge damping ratio testing system is provided, the system comprising:

[0039] A modeling and analysis module is used to construct a corresponding bridge structure finite element model for the bridge to be tested, and use the bridge structure finite element model to perform structural dynamic simulation analysis to obtain the bridge structure theoretical modal parameter frequency and bridge vibration mode corresponding to the bridge to be tested;

[0040] The first dynamic characteristic analysis module is used to intermittently collect vibration data and corresponding natural environment parameters of the bridge to be tested under various natural environment excitations according to a preset collection period, so as to obtain environmental excitation vibration data; perform modal fitting analysis on the environmental excitation vibration data according to the theoretical modal parameter frequency of the bridge structure and the bridge vibration mode corresponding to the bridge to be tested, so as to obtain dynamic characteristic parameters of each order vibration mode of the bridge to be tested under various natural environment excitations;

[0041] The second dynamic characteristic analysis module is used to collect the structural dynamic response of the vibration vehicle in the process of continuously vibrating the characteristic position of the bridge to be tested by continuously jumping the vehicle through the test obstacle based on the dynamic characteristic parameters under the natural environment excitation, and obtain the dynamic characteristic parameters of the bridge to be tested under artificial excitation of each vibration mode according to the structural dynamic response;

[0042] The damping ratio analysis module is used to perform modal fitting analysis on the dynamic characteristic parameters under artificial excitation of each order vibration mode according to the bridge structure theoretical modal parameter frequency and bridge vibration mode corresponding to the bridge to be tested, so as to obtain the damping ratio corresponding to each order vibration mode of the bridge to be tested.

[0043] According to a third aspect of an embodiment of the present invention, there is provided a bridge damping ratio testing device, the device comprising: a processor and a memory;

[0044] The memory is used to store one or more program instructions;

[0045] The processor is used to run one or more program instructions to execute the steps of a bridge damping ratio testing method as described in any one of the above items.

[0046] According to a fourth aspect of an embodiment of the present invention, a computer program product is provided, the computer program product comprising a computer program stored on a non-transitory computer-readable storage medium, the computer program comprising program instructions, which, when executed by a computer, enable the computer to implement the steps of a bridge damping ratio testing method as described in any one of the above items.

[0047] The embodiments of the present invention have the following advantages:

[0048] 1. The embodiment of the present invention achieves the technical effect of maximizing the vibration energy of high-order vibration modes through a cheaper continuous vibration excitation method using an excitation vehicle, avoids the use of large-scale excitation equipment during artificial excitation, and provides a method that is more convenient for on-site implementation for dynamic characteristics testing of large-span bridges. It is more economical and convenient than using large-scale excitation equipment for excitation.

[0049] 2. The embodiment of the present invention uses a method of continuous jumping of a loaded vehicle to excite the sensitive parts of the bridge, so that the mass participation percentage of the high-order frequency vibration mode of the bridge to be tested is greatly improved compared with the natural environment excitation, so that the energy of a certain high-order vibration mode of the bridge to be tested reaches the maximum, so that the damping ratio test and analysis results of a certain high-order vibration mode are more accurate.

[0050] 3. When collecting the dynamic structural response of the vehicle excitation, the embodiment of the present invention adopts a method for determining the collection time based on the amplitude recovery state, which greatly shortens the test time and improves the test work efficiency.

[0051] 4. The bridge damping ratio testing method provided by the embodiment of the present invention effectively solves the problems of large error, low precision and low efficiency of the existing damping ratio testing method. The measured bridge damping ratio is more comprehensive and accurate, and is particularly suitable for the damping ratio testing of large-span cable-stayed bridges, suspension bridges and large-span beam bridges. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0053] Figure 1 A schematic flow chart of a bridge damping ratio testing method provided by an embodiment of the present invention;

[0054] Figure 2 A schematic diagram of the first-order symmetrical vertical bending vibration mode of the main beam of a long-span cable-stayed bridge provided by an embodiment of the present invention;

[0055] Figure 3 A schematic diagram of the first-order antisymmetric vertical bending vibration mode of the main beam of a long-span cable-stayed bridge provided by an embodiment of the present invention;

[0056] Figure 4 A schematic diagram of the second-order symmetrical vertical bending vibration mode of the main beam of a long-span cable-stayed bridge provided by an embodiment of the present invention;

[0057] Figure 5 A schematic diagram of the second-order antisymmetric vertical bending vibration mode of the main beam of a long-span cable-stayed bridge provided by an embodiment of the present invention;

[0058] Figure 6 A schematic diagram of the third-order symmetrical vertical bending vibration mode of the main beam of a long-span cable-stayed bridge provided by an embodiment of the present invention;

[0059] Figure 7 A schematic structural diagram of a bridge damping ratio testing system provided by an embodiment of the present invention;

[0060] Figure 8 A schematic diagram of the test section and measurement point arrangement for testing the dynamic characteristics of a bridge structure under natural environmental excitation conditions of a suspension bridge provided in an embodiment of the present invention;

[0061] Fig. 9 A schematic diagram of the test section and measurement point arrangement for testing the dynamic characteristics of a bridge structure under natural environmental excitation conditions of a cable-stayed bridge provided in an embodiment of the present invention;

[0062] Fig.10 A schematic diagram of the test section and measurement point arrangement for testing the dynamic characteristics of a bridge structure under natural environmental excitation conditions of a beam bridge provided in an embodiment of the present invention;

[0063] Fig.11 A schematic cross-sectional view of a test obstacle provided by an embodiment of the present invention;

[0064] Fig.12 A schematic diagram of the test obstacle arrangement positions and vibration pickup arrangement positions applicable to suspension bridges and cable-stayed bridges under vehicle excitation conditions provided in an embodiment of the present invention;

[0065] Fig.13 A schematic diagram of the test obstacle arrangement positions and vibration pickup arrangement positions applicable to vehicle excitation conditions of a long-span beam bridge provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0066] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0067] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0068] In order to solve the defects of the prior art, the present invention provides a bridge damping ratio testing method. Through simulation analysis, environmental excitation collection analysis, and continuous vehicle jumping excitation collection analysis, a complete bridge damping ratio testing system is obtained, which can test the damping ratio of a large-span bridge more economically, efficiently, and accurately, thereby overcoming the problems of the prior art that the high-order modal recognition accuracy is insufficient when simply using environmental excitation testing and the output force of artificial excitation equipment is limited.

[0069] Figure 1 The figure shows a flow chart of a bridge damping ratio testing method according to an embodiment of the present invention.

[0070] like Figure 1 As shown, the bridge damping ratio testing method according to the embodiment of the present invention may include step S100, step S200, step S300, step S400 and step S500.

[0071] In step S100, for the bridge to be tested, a corresponding bridge structure finite element model is constructed, and the bridge structure finite element model is used to perform structural dynamic simulation analysis to obtain the bridge structure theoretical modal parameter frequency and bridge vibration shape corresponding to the bridge to be tested.

[0072] Specifically, the above steps are used to accurately simulate the constraints, load mass, etc. of the bridge structure to be tested, and obtain the accurate theoretical model and corresponding parameter frequency corresponding to the bridge to be tested.

[0073] If the bridge to be tested is a long-span cable-stayed bridge or a long-span suspension bridge, at least the first nine vibration modes of the bridge to be tested are extracted; if the bridge to be tested is a long-span beam bridge, at least the first three vibration modes of the bridge to be tested are extracted.

[0074] Figures 2 to 6 It is a partial vibration diagram of a long-span cable-stayed bridge, where: Figure 2 The figure shows a schematic diagram of the first-order symmetrical vertical bending vibration mode of the main beam of a long-span cable-stayed bridge; Figure 3The figure shows the schematic diagram of the first-order antisymmetric vertical bending vibration mode of the main beam of a long-span cable-stayed bridge; Figure 4 The figure shows a schematic diagram of the second-order symmetrical vertical bending vibration mode of the main beam of a long-span cable-stayed bridge; Figure 5 The figure shows the schematic diagram of the second-order antisymmetric vertical bending vibration mode of the main beam of a long-span cable-stayed bridge; Figure 6 The figure shows a schematic diagram of the third-order symmetrical vertical bending vibration mode of the main beam of a long-span cable-stayed bridge.

[0075] Next, in step S200, according to a preset collection period, vibration data of the bridge to be tested under various natural environment excitations and corresponding natural environment parameters are intermittently collected to obtain environmental excitation vibration data.

[0076] Specifically, the above steps include: formulating a vibration data collection plan for the environmental excitation method, intermittently collecting 12 groups of pulsation data under different natural environmental conditions according to the preset collection period, with 2 hours as a vibration data collection period, and recording the natural environmental parameters at the beginning and end of the test to obtain environmental excitation vibration data.

[0077] Among them, the above-mentioned natural environment parameters include parameters such as temperature, wind speed and wind direction; the above-mentioned preset collection period includes the highest temperature period and the lowest temperature period in a day, with 2 hours as a vibration data collection period, and the pulsation data collection time of each period is 45 minutes to 1 hour.

[0078] In step S300, according to the theoretical modal parameter frequency of the bridge structure and the bridge vibration mode corresponding to the bridge to be tested, the environmental excitation vibration data is subjected to modal fitting analysis and processing to obtain the dynamic characteristic parameters of each order vibration mode of the bridge to be tested under various natural environmental excitations.

[0079] The above-mentioned modal fitting analysis and processing includes two or more data analysis and processing methods such as enhanced frequency domain decomposition method EFDD and time domain analysis method datedriver SSI.

[0080] Figure 8 The figure shows the test section and measurement point layout diagram for the dynamic characteristics test of the bridge structure under the natural environment excitation conditions of the suspension bridge. Fig. 9 The figure shows the test section and measurement point layout diagram for the bridge structure dynamic characteristics test under natural environment excitation conditions of cable-stayed bridges. Fig.10 The figure shows a schematic diagram of the test section and measurement point arrangement suitable for testing the dynamic characteristics of a bridge structure under natural environmental excitation conditions of a beam bridge, wherein the vibration pickup 1 is a vibration pickup for dynamic characteristics testing.

[0081] Next, in step S400, based on the dynamic characteristic parameters under natural environment excitation, the structural dynamic response of the vibration vehicle in the process of continuously vibrating the characteristic position of the bridge to be tested by continuously jumping over the test obstacle is collected, and the dynamic characteristic parameters of the bridge to be tested under artificial excitation of each vibration mode are obtained according to the structural dynamic response.

[0082] The above steps specifically include: first, according to the dynamic characteristic parameters of each vibration mode of the bridge to be tested under various natural environment excitations, a vehicle excitation test plan under each vibration mode is formulated, and the average natural frequency of each vibration mode under all natural environment excitations is calculated.

[0083] Then, according to the preset driving speed of the exciting vehicle, the obstacle spacing is calculated using the average value of the natural frequency of each vibration mode. The calculation formula is:

[0084] d=v / f

[0085] Wherein, d is the obstacle distance, v is the speed of the exciting vehicle, and f is the average natural frequency of each vibration mode under all natural environment excitations. The above exciting vehicle has a load of 350kN and a preset speed of 10km / h or 20km / h.

[0086] According to the theoretical results of dynamic characteristic parameters of the bridge to be tested obtained through structural dynamic simulation analysis, the area with the largest bending degree of each vibration mode of the bridge to be tested is taken as the excitation area.

[0087] According to the obstacle spacing, a group of test obstacles are arranged as the excitation positions in the excitation area based on the characteristic positions such as the bisection point, the quarter point, and the eighth point of the span, and two groups of test obstacles are arranged on both sides as the excitation positions. A total of five groups of test obstacles are arranged in the excitation area; at the same time, the vibration pickups for dynamic characteristic tests corresponding to the test obstacles are arranged on one side of each test obstacle, where: Fig.11 The figure shows a schematic cross-section of the test obstacle.

[0088] The excitation vehicle is used to continuously pass the test obstacle at a constant speed at a preset speed, and the excitation vehicle jumps at the test obstacle position, thereby achieving continuous excitation of the characteristic position of the bridge to be tested at a preset frequency.

[0089] In order to solve the problem of small amplitude of high-order vibration modes of long-span bridges, the present invention increases the amplitude to a recognizable level by controlling the weight of the load-carrying vehicle, the height of the obstacle and the number of obstacles in the characteristic area, and arranges measuring points at vibration-sensitive positions to pick up vibration parameters, so that the vibration energy corresponding to a certain order vibration mode to be measured is maximized, thereby improving the test accuracy. Specifically, a method for setting five groups of obstacles for continuous excitation is provided. Long-span bridges are generally long. The embodiment of the present invention adopts a continuous vehicle jumping excitation method, and there is no need to continuously excite the entire bridge. The excitation position is selected according to simulation analysis in the area where the excitation effect is most obvious under a certain vibration mode. A group of obstacles are arranged in the area based on characteristic positions such as the bisection point, the quarter point and the eighth point of the span, and two groups of obstacles are arranged on both sides to form continuous excitation of five groups of obstacles in the characteristic area.

[0090] Fig.12 The figure shows the schematic diagram of the test obstacle layout and vibration pickup layout under vehicle excitation conditions applicable to suspension bridges and cable-stayed bridges. Fig.13 The figure shows a schematic diagram of the test obstacle layout and vibration pickup layout under vehicle excitation conditions suitable for long-span beam bridges, wherein vibration pickup 1 is a vibration pickup for dynamic characteristics testing, and obstacle 2 is a driving test obstacle for vehicle excitation.

[0091] The structural dynamic response is collected before the excitation vehicle goes on the bridge, and the collection is continued until the amplitude at the excitation position is restored. The dynamic characteristic parameters of each vibration mode of the bridge to be tested under excitation and residual vibration are obtained using the collected structural dynamic response.

[0092] The embodiment of the present invention provides a method for determining the acquisition duration based on the amplitude recovery state. Sampling can be stopped after the amplitude of the vehicle excitation point is restored, so that the sampling duration is greatly shortened compared with the traditional sampling duration based on experience, and the test efficiency is effectively improved.

[0093] Finally, in step S500, according to the theoretical modal parameter frequency of the bridge structure and the bridge vibration mode corresponding to the bridge to be tested, the modal fitting analysis and processing is performed on the dynamic characteristic parameters under artificial excitation of each vibration mode to obtain the damping ratio of the bridge to be tested under artificial excitation of each vibration mode at different preset vehicle speeds.

[0094] In summary, in order to achieve various resonances of the bridge during vehicle excitation, the vibration data collection scheme based on the continuous vehicle jumping excitation method provided by the embodiment of the present invention calculates the obstacle interval of the excitation vehicle according to the measured average frequency under environmental excitation conditions and the vehicle speed, and jumps the vehicle at equal intervals of the uniformly traveling vehicle to obtain an external excitation force of equal frequency provided to the bridge structure when the excitation vehicle is traveling at a preset speed, thereby increasing the amplitude of the corresponding frequency of the bridge. By collecting the dynamic characteristic response parameters near the excitation position, the problem of large error in the damping ratio test result due to the small amplitude of the large-span bridge is effectively solved.

[0095] In addition, the embodiment of the present invention also provides a bridge damping ratio test system, referring to Figure 7 , the above system specifically includes:

[0096] The modeling and analysis module is used to construct a corresponding bridge structure finite element model for the bridge to be tested, and use the bridge structure finite element model to perform structural dynamic simulation analysis to obtain the bridge structure theoretical modal parameter frequency and bridge vibration shape corresponding to the bridge to be tested;

[0097] The first dynamic characteristic analysis module is used to intermittently collect vibration data and corresponding natural environment parameters of the bridge to be tested under various natural environment excitations according to a preset collection period, and obtain environmental excitation vibration data; according to the theoretical modal parameter frequency of the bridge structure and the bridge vibration mode corresponding to the bridge to be tested, the environmental excitation vibration data is subjected to modal fitting analysis and processing, and the dynamic characteristic parameters of each order vibration mode of the bridge to be tested under various natural environment excitations are obtained;

[0098] The second dynamic characteristic analysis module is used to collect the structural dynamic response of the vibration vehicle in the process of continuous vibration of the characteristic position of the bridge to be tested by continuously jumping over the test obstacle based on the dynamic characteristic parameters under the excitation of the natural environment, and obtain the dynamic characteristic parameters of the bridge to be tested under artificial excitation of each vibration mode according to the structural dynamic response;

[0099] The damping ratio analysis module is used to perform modal fitting analysis on the dynamic characteristic parameters under artificial excitation of each order vibration mode according to the theoretical modal parameter frequency of the bridge structure and the bridge vibration mode corresponding to the bridge to be tested, so as to obtain the damping ratio corresponding to each order vibration mode of the bridge to be tested.

[0100] In addition, an embodiment of the present invention further provides a device, which includes: a processor and a memory; the memory is used to store one or more program instructions; the processor is used to run one or more program instructions to execute the steps of a bridge damping ratio testing method as described above.

[0101] In addition, an embodiment of the present invention further provides a computer program product, which includes computer program instructions. When the computer program instructions are executed by a processor, the steps of the bridge damping ratio testing method described above are implemented.

[0102] A bridge damping ratio testing method, system, device and program product provided by the embodiments of the present invention have at least the following advantages:

[0103] 1. The embodiment of the present invention achieves the technical effect of maximizing the vibration energy of high-order vibration modes through a cheaper continuous vibration excitation method using an excitation vehicle, avoids the use of large-scale excitation equipment during artificial excitation, and provides a method that is more convenient for on-site implementation for dynamic characteristics testing of large-span bridges. It is more economical and convenient than using large-scale excitation equipment for excitation.

[0104] 2. The embodiment of the present invention uses a method of continuous jumping of a loaded vehicle to excite the sensitive parts of the bridge, so that the mass participation percentage of the high-order frequency vibration mode of the bridge to be tested is greatly improved compared with the natural environment excitation, so that the energy of a certain high-order vibration mode of the bridge to be tested reaches the maximum, so that the damping ratio test and analysis results of a certain high-order vibration mode are more accurate.

[0105] 3. When collecting the dynamic structural response of the vehicle excitation, the embodiment of the present invention adopts a method for determining the collection time based on the amplitude recovery state, which greatly shortens the test time and improves the test work efficiency.

[0106] 4. The bridge damping ratio testing method provided by the embodiment of the present invention effectively solves the problems of large error, low precision and low efficiency of the existing damping ratio testing method. The measured bridge damping ratio is more comprehensive and accurate, and is particularly suitable for the damping ratio testing of large-span cable-stayed bridges, suspension bridges and large-span beam bridges.

[0107] In the embodiment of the present invention, the processor may be an integrated circuit chip with signal processing capability. The processor may be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic devices, discrete gates or transistor logic devices, or discrete hardware components. The methods, steps, and logic block diagrams disclosed in the embodiments of the present invention may be implemented or executed. The general-purpose processor may be a microprocessor or the processor may be any conventional processor, etc. The steps of the method disclosed in the embodiment of the present invention may be directly embodied as being executed by a hardware decoding processor, or may be executed by a combination of hardware and software modules in a decoding processor. The software module may be located in a mature storage medium in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, or an electrically erasable programmable memory, a register, etc. The processor reads the information in the storage medium and completes the steps of the above method in combination with its hardware. The storage medium may be a memory, for example, a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory can be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory can be a random access memory (RAM), which is used as an external cache. By way of example but not limitation, many forms of RAM are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDRSDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM) and direct memory bus random access memory (Direct Rambus RAM, DRRAM).The storage medium described in the embodiment of the present invention is intended to include but is not limited to these and any other suitable types of memory. Those skilled in the art should be aware that in one or more of the above examples, the functions described in the present invention can be implemented by a combination of hardware and software. When the software is applied, the corresponding function can be stored in a computer-readable medium or transmitted as one or more instructions or codes on a computer-readable medium. Computer-readable media include computer storage media and communication media, wherein the communication medium includes any medium that is convenient for transmitting a computer program from one place to another. The storage medium can be any available medium that a general or special-purpose computer can access. Although the present invention has been described in detail above with general descriptions and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements can be made to it on the basis of the present invention. Therefore, these modifications or improvements made on the basis of not departing from the spirit of the present invention all belong to the scope of protection claimed in the present invention.

Claims

1. A bridge damping ratio testing method, characterized in that: The method comprises: For the bridge to be tested, a corresponding bridge structure finite element model is constructed, and the bridge structure finite element model is used to perform structural dynamic simulation analysis to obtain the bridge structure theoretical modal parameter frequency and bridge vibration mode corresponding to the bridge to be tested; According to a preset collection period, intermittently collect vibration data of the bridge to be tested under various natural environment excitations and corresponding natural environment parameters to obtain environmental excitation vibration data; According to the theoretical modal parameter frequency of the bridge structure and the bridge vibration mode corresponding to the bridge to be tested, the modal fitting analysis and processing is performed on the environmental excitation vibration data to obtain the dynamic characteristic parameters of each order vibration mode of the bridge to be tested under various natural environment excitations; Based on the dynamic characteristic parameters under the excitation of the natural environment, the structural dynamic response of the vibration vehicle in the process of continuously exciting the characteristic position of the bridge to be tested by continuously jumping through the test obstacle is collected, and the dynamic characteristic parameters of the bridge to be tested under artificial excitation of each vibration mode are obtained according to the structural dynamic response; According to the theoretical modal parameter frequency of the bridge structure and the bridge vibration mode corresponding to the bridge to be tested, the dynamic characteristic parameters under artificial excitation of each vibration mode are subjected to modal fitting analysis to obtain the damping ratio corresponding to each vibration mode of the bridge to be tested.

2. A bridge damping ratio testing method as claimed in claim 1, characterized in that: The structural dynamic simulation analysis is performed using the bridge structure finite element model to obtain the bridge structure theoretical modal parameter frequency and bridge vibration mode corresponding to the bridge to be tested, including: If the bridge to be tested is a long-span cable-stayed bridge or a long-span suspension bridge, at least the first nine vibration modes of the bridge to be tested are extracted; If the bridge to be tested is a long-span beam bridge, at least the first three vibration modes of the bridge to be tested are extracted.

3. A bridge damping ratio testing method as claimed in claim 1, characterized in that: The natural environment parameters include temperature, wind speed and wind direction; The preset collection period includes the highest temperature period and the lowest temperature period in a day.

4. A bridge damping ratio testing method as claimed in claim 1, characterized in that: The modal fitting analysis process includes an enhanced frequency domain decomposition method and a time domain analysis method.

5. A bridge damping ratio testing method as claimed in claim 1, characterized in that: Based on the dynamic characteristic parameters under natural environment excitation, the structural dynamic response of the vibration vehicle in the process of continuously exciting the characteristic position of the bridge to be tested by continuously jumping through the test obstacle is collected. According to the structural dynamic response, the dynamic characteristic parameters of the bridge to be tested under artificial excitation of each vibration mode are obtained, including: Using the dynamic characteristic parameters of each vibration mode of the bridge to be tested under various natural environment excitations, the average value of the natural frequency of each vibration mode under all natural environment excitations is calculated; According to the driving speed of the exciting vehicle, the obstacle spacing is calculated using the average value of the natural frequency of each vibration mode. The calculation formula is: d=v / f Where d is the obstacle distance, v is the speed of the exciting vehicle, and f is the average natural frequency of each vibration mode under all natural environment excitations; According to the obstacle spacing, at least two groups of test obstacles are set on the bridge to be tested, and an exciting vehicle is used to continuously pass through the test obstacles at a uniform speed at a preset speed, and the characteristic position of the bridge to be tested is continuously excited at a preset frequency by continuously jumping the vehicle.

6. A bridge damping ratio testing method as claimed in claim 1, characterized in that: Based on the dynamic characteristic parameters under the excitation of the natural environment, the structural dynamic response of the vibration vehicle in the process of continuously exciting the characteristic position of the bridge to be tested by continuously jumping through the test obstacle is collected, and the dynamic characteristic parameters of the bridge to be tested under artificial excitation of each vibration mode are obtained according to the structural dynamic response, which also includes: Collect the structural dynamic response from before the exciting vehicle goes on the bridge to when the amplitude at the exciting position recovers; By using the structural dynamic response, the dynamic characteristic parameters of the bridge to be tested under artificial excitation of each vibration mode under excitation and residual vibration are obtained.

7. A bridge damping ratio testing method as claimed in claim 5, characterized in that: According to the obstacle spacing, at least two groups of test obstacles are set on the bridge to be tested, including: According to the theoretical results of dynamic characteristic parameters obtained through structural dynamic simulation analysis of the bridge to be tested, the area with the largest bending degree of the bridge to be tested is taken as the excitation area; Arranging at least two groups of test obstacles in the excitation area; Arrange vibration pickups for dynamic characteristic testing corresponding to the test obstacles on one side of each test obstacle; The energy of each vibration mode is adjusted by using the weight of the exciting vehicle, the height of the obstacle, and the number of obstacles in the characteristic area during artificial excitation.

8. A bridge damping ratio test system, characterized in that: The system comprises: A modeling and analysis module is used to construct a corresponding bridge structure finite element model for the bridge to be tested, and use the bridge structure finite element model to perform structural dynamic simulation analysis to obtain the bridge structure theoretical modal parameter frequency and bridge vibration mode corresponding to the bridge to be tested; The first dynamic characteristic analysis module is used to intermittently collect vibration data and corresponding natural environment parameters of the bridge to be tested under various natural environment excitations according to a preset collection period, so as to obtain environmental excitation vibration data; perform modal fitting analysis on the environmental excitation vibration data according to the theoretical modal parameter frequency of the bridge structure and the bridge vibration mode corresponding to the bridge to be tested, so as to obtain dynamic characteristic parameters of each order vibration mode of the bridge to be tested under various natural environment excitations; The second dynamic characteristic analysis module is used to collect the structural dynamic response of the vibration vehicle in the process of continuously vibrating the characteristic position of the bridge to be tested by continuously jumping the vehicle through the test obstacle based on the dynamic characteristic parameters under the natural environment excitation, and obtain the dynamic characteristic parameters of the bridge to be tested under artificial excitation of each vibration mode according to the structural dynamic response; The damping ratio analysis module is used to perform modal fitting analysis on the dynamic characteristic parameters under artificial excitation of each order vibration mode according to the bridge structure theoretical modal parameter frequency and bridge vibration mode corresponding to the bridge to be tested, so as to obtain the damping ratio corresponding to each order vibration mode of the bridge to be tested.

9. A bridge damping ratio test device, characterized in that: The device comprises: a processor and a memory; The memory is used to store one or more program instructions; The processor is used to run one or more program instructions to execute the steps of a bridge damping ratio testing method as described in any one of claims 1 to 7.

10. A computer program product, characterized in that The computer program product comprises computer program instructions, which, when executed by a processor, implement the steps of a bridge damping ratio testing method as claimed in any one of claims 1 to 7.

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