Damping method for stay cable and main beam based on damper mounting position

Abstract

The invention provides a damping method for stay cables and a main beam based on damper mounting positions, which comprises the following steps of: establishing a finite element model about the main beam and each stay cable, and performing modal analysis on the finite element model to obtain a vibration mode of each stay cable and a vibration response characteristic of the main beam; aiming at the target stay cable, determining a standard mounting interval of an external damper arranged between the target stay cable and the main beam; in the standard installation interval, the additional damping ratios of the main beam at different positions are calculated by adjusting the position of the external damper and combining the vibration amplitude change of the main beam, and the maximum value of the additional damping ratios of the main beam is selected as a target installation position; according to the step of determining the target installation position of the target stay cable, the target installation position corresponding to each external damper is obtained, and the external dampers are arranged according to the corresponding target installation positions. The installation positions of the external dampers between the stay cables and the main beam are determined, and vibration of the main beam and the stay cables is relieved most effectively.

Description

Technical Field

[0001] The present application relates to the technical field of vibration control of cable-stayed bridges, and in particular to a vibration reduction method for a cable-stayed bridge and a main beam based on the installation position of a damper. Background Art

[0002] In recent years, the span capacity of long-span cable-stayed bridges has been significantly improved by introducing new technologies, new theories, new structures, new materials and new processes. As the span of bridges continues to increase, the main beams have become lighter, and the quality and length of the cables have continued to increase, which has increased the slenderness ratio and flexibility of the cables. Since the cables themselves have low initial damping, the main beams and cables of cable-stayed bridges are more likely to vibrate under the stimulation of wind, rain and other external loads.

[0003] In the prior art, in order to solve the vibration problem of the cable and the main beam, the main method is to install an external damper between the cable and the main beam. The damping parameters of the external damper and the additional damping ratio of the main beam directly affect the vibration reduction effect of the cable and the main beam, and the connection position of the external damper relative to the target cable and the main beam will directly change its own damping and the additional damping ratio of the main beam, thereby affecting the vibration reduction effect of the cable and the main beam; therefore, how to optimize the installation position of the external damper between each cable and the main beam to most effectively reduce the vibration of the main beam and the cable is particularly important. Summary of the invention

[0004] An embodiment of the present application provides a vibration reduction method for inclined cables and main beams based on the installation position of dampers to solve the problem in the related art of how to determine the installation position of external dampers between each inclined cable and the main beam to most effectively reduce the vibration of the main beam and the inclined cables.

[0005] In a first aspect, a vibration reduction method for a cable-stayed cable and a main beam based on a damper installation position is provided, which includes: establishing a finite element model of the main beam and each cable, and performing a modal analysis on the model to obtain the vibration mode of each cable and the vibration response characteristics of the main beam; for a target cable-stayed cable, based on its vibration mode and the vibration response characteristics of the main beam, analyzing the vibration coupling effect between the cable-stayed cable and the main beam, and determining a standard installation range of an external damper set between the target cable-stayed cable and the main beam; within the standard installation range, by adjusting the position of the external damper, combining the change in the vibration amplitude of the main beam, calculating the additional damping ratio of the main beam at different positions, and selecting the maximum value of the additional damping ratio of the main beam as the target installation position; according to the step of determining the target installation position of the target cable-stayed cable, obtaining the target installation position corresponding to the external damper set between each cable-stayed cable and the main beam, and setting the external damper between each cable-stayed cable and the main beam according to the corresponding target installation position.

[0006] In some embodiments, the length of the cable is denoted as L, the connection point between the cable and the bridge deck is denoted as point M, and the distance between the connection point between the target damper and the target cable and point M is denoted as x, and the first threshold range is defined as: A={x|0.005L<x≤0.05L}; the value falling within the first threshold range in the standard installation interval of each cable is obtained, and updated as the standard installation interval of the corresponding cable.

[0007] In some embodiments, within the standard installation range, by adjusting the position of the external damper and combining the vibration amplitude change of the main beam, the additional damping ratio of the main beam at different positions is calculated, which includes the following steps: Based on the vibration response characteristics of the main beam, the peak value of the vertical vibration mode displacement of the main beam with the external damper located at the target installation position is obtained; in combination with the finite element model, a vertical simple harmonic load is applied at the peak value of the vertical vibration mode displacement of the main beam, and then the vertical simple harmonic load is unloaded, and the vibration attenuation process of the main beam is analyzed to obtain the displacement time history data; based on the displacement time history data, the additional damping ratio of the main beam is calculated by the second formula; the above steps are repeated to obtain the additional damping ratio of the main beam when the external damper is installed at different positions.

[0008] In some embodiments, applying a vertical simple harmonic load at the peak of the vertical vibration mode displacement of the main beam comprises the following steps: Obtain the vertical natural frequency of the main beam with the target damper at the target installation position, that is, the second natural frequency, denoted as ωn; denote the vertical simple harmonic load as P, the excitation load amplitude as F, and the loading time as t; according to , vertical simple harmonic load is continuously applied to the peak of the vertical vibration mode displacement of the main beam, where , N is the number of natural vibration periods, which is adjusted based on the main beam vibration data.

[0009] In some embodiments, the modal analysis includes the following: extracting the first three vibration modes of each inclined cable and the fundamental frequency vibration mode of the main beam, and quantifying the vibration amplitude distribution of the main beam under different frequency excitations through harmonic response analysis.

[0010] In some embodiments, the analysis of the vibration coupling effect is achieved in the following manner: modally superimposing the vibration mode of the main beam and the vibration mode of the inclined cable to identify the resonance risk area; calculating the energy transfer coefficient between the main beam and the inclined cable, and selecting the inclined cable whose energy transfer coefficient is greater than the first standard value as the priority optimization target.

[0011] In some embodiments, before the vibration reduction method of the cable-stayed cables and main beams based on the damper installation position is implemented, an on-site environmental vibration test is performed on the cable-stayed bridge to obtain actual vibration spectrum data, and the finite element model is corrected based on the actual vibration spectrum data.

[0012] In some embodiments, the external damper is a part of a cable-stayed damper device, which also includes a support, a connecting piece and a main lever. The connecting piece is used to connect to the cable, one end of the main lever is fixedly connected to the connecting piece, and the other end is rotatably connected to the support; the target damper is respectively connected to the upper and lower ends of the main lever.

[0013] In some embodiments, the target damper includes an in-plane damper, an in-plane lever, an out-of-plane damper, an out-of-plane lever, and an out-of-plane link; a first ear plate, a second ear plate, and a third ear plate are provided on the support; the in-plane damper is rotationally connected to the second ear plate, the middle part of the in-plane lever is rotationally connected to the main lever, one end of the in-plane lever is rotationally connected to the first ear plate, and the other end is connected to the in-plane damper; the out-of-plane damper is rotationally connected to the middle part of the main lever, one end of the out-of-plane link is rotationally connected to the bottom of the main lever, one end of the out-of-plane lever is rotationally connected to the out-of-plane link, the other end of the out-of-plane lever is rotationally connected to the out-of-plane damper, and the middle part of the out-of-plane lever is rotationally connected to the third ear plate.

[0014] In some embodiments, the included angle between the cable damper device and the cable is 90°.

[0015] The beneficial effects brought by the technical solution provided in the embodiments of the present application include: The embodiment of the present application provides a vibration reduction method for the cable and the main beam based on the installation position of the damper. By establishing a finite element model of the main beam and the cable and performing a modal analysis on them, the vibration mode of each cable and the vibration response characteristics of the main beam are obtained, the dynamic characteristics of the structure are revealed, and data support is provided for subsequent optimization; the vibration mode of the cable and the vibration response characteristics of the main beam are combined to analyze the vibration coupling effect between the two, and the interaction area between the cable and the main beam is identified through modal superposition and energy transfer coefficient calculation to avoid the global resonance problem caused by local vibration. The standard installation interval is set based on the vibration energy concentration area, and the quantitative calculation of the additional damping ratio is performed to ensure the accuracy of the position optimization, and the optimal installation position is independently determined for each cable, and the external damper is uniformly installed; the vibration sensitive area is accurately located through the finite element model and modal analysis, and the quantitative calculation of the additional damping ratio is combined to avoid the blindness of the traditional empirical method and maximize the energy absorption efficiency of the damper; the vibration coupling effect analysis ensures that the installation of the damper not only suppresses the local vibration of the cable, but also reduces the resonance risk of the main beam and the cable, thereby improving the dynamic stability of the overall structure. Through the closed-loop process of "modeling, analysis, optimization, and implementation", theoretical calculations and engineering practice are closely combined to solve the problem of optimizing the damper installation position. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram of a process for determining a damper installation position provided in an embodiment of the present application; Figure 2A schematic diagram of the installation and application of the stay cable damper device provided in an embodiment of the present application; Figure 3 A schematic diagram of the specific structure of the cable-stayed damper device provided in an embodiment of the present application.

[0017] In the figure: 1. cable-stayed damper device; 2. cable-stayed cable; 3. support; 31. first ear plate; 32. second ear plate; 33. third ear plate; 4. connecting member; 5. main lever; 6. in-plane damper; 7. in-plane lever; 8. out-of-plane damper; 9. out-of-plane lever; 10. out-of-plane link rod. DETAILED DESCRIPTION

[0018] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0019] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below with reference to the accompanying drawings.

[0020] In the first aspect, the embodiment of the present application provides a vibration reduction method for a cable and a main beam based on the installation position of a damper, referring to Figure 1 , Figure 1 A schematic diagram of a process for determining the damper installation position provided in an embodiment of the present application. Figure 1 As shown, the vibration reduction methods of the cable and the main beam based on the damper installation position include: S1. Establish a finite element model of the main beam and each inclined cable, and perform modal analysis on it to obtain the vibration mode of each inclined cable and the vibration response characteristics of the main beam; S2. Analyze the vibration coupling effect between the target cable and the main beam based on its vibration mode and the vibration response characteristics of the main beam, and determine the standard installation range of the external damper set between the target cable and the main beam; S3. Within the standard installation range, by adjusting the position of the external damper, the additional damping ratio of the main beam at different positions is calculated in combination with the vibration amplitude change of the main beam, and the maximum value of the additional damping ratio of the main beam is selected as the target installation position; S4. According to the step of determining the target installation position of the target inclined cable, the target installation position corresponding to the external damper set between each inclined cable and the main beam is obtained, and the external damper is set between each inclined cable and the main beam according to the corresponding target installation position.

[0021] In this embodiment, by establishing finite element models of the main beam and the cable and performing modal analysis on them, the vibration modes of each cable and the vibration response characteristics of the main beam are obtained, the dynamic characteristics of the structure are revealed, and data support is provided for subsequent optimization; the vibration modes of the cable and the vibration response characteristics of the main beam are combined to analyze the vibration coupling effect between the two, and the interaction area between the cable and the main beam is identified through modal superposition and energy transfer coefficient calculation to avoid global resonance problems caused by local vibration. The standard installation range is set based on the vibration energy concentration area, and the quantitative calculation of the additional damping ratio is used to ensure the accuracy of position optimization, and the optimal installation position is independently determined for each cable, and external dampers are uniformly installed; the vibration sensitive area is accurately located through the finite element model and modal analysis, and the quantitative calculation of the additional damping ratio is combined to avoid the blindness of the traditional empirical method and maximize the energy absorption efficiency of the damper; the vibration coupling effect analysis ensures that the installation of the damper not only suppresses the local vibration of the cable, but also reduces the resonance risk of the main beam and the cable, thereby improving the dynamic stability of the overall structure. Through the closed-loop process of "modeling, analysis, optimization, and implementation", theoretical calculations are closely integrated with engineering practice, the problem of optimizing the damper installation position is solved, and the problem of how to determine the installation position of the external damper between each inclined cable and the main beam in the relevant technology is solved to most effectively reduce the vibration of the main beam and the inclined cable.

[0022] Furthermore, in one embodiment, the length of the cable is denoted as L, the connection point between the cable and the bridge deck is denoted as point M, and the distance between the connection point between the target damper and the target cable and point M is denoted as x, and the first threshold range is limited: A={x|0.005L<x≤0.05L}; the value falling within the first threshold range in the standard installation interval of each cable is obtained, and updated as the standard installation interval of the corresponding cable.

[0023] In this embodiment, the position range of the connection point between the external damper and the cable is limited to 0.005L to 0.05L of the total length of the cable, that is, 0.5% to 5%. Installing the damper in the area close to the main beam can more effectively block the transmission of the main beam vibration to the cable and reduce the source of energy input; the setting of the first threshold range A avoids the installation position of the damper from deviating from the sensitive area due to construction errors; by narrowing the candidate interval, the calculation amount of the finite element model is reduced.

[0024] Furthermore, in one embodiment, within the standard installation range, the additional damping ratio of the main beam at different positions is calculated by adjusting the position of the external damper and combining the change in the vibration amplitude of the main beam, which includes the following steps: based on the vibration response characteristics of the main beam, obtaining the peak vertical vibration mode displacement of the main beam where the external damper is located at the target installation position; combining with the finite element model, and applying a vertical simple harmonic load at the peak vertical vibration mode displacement of the main beam, then unloading the vertical simple harmonic load, and analyzing the vibration attenuation process of the main beam to obtain displacement time-history data; according to the displacement time-history data, and using the second formula to calculate the additional damping ratio of the main beam; repeating the above steps to obtain the additional damping ratio of the main beam when the external damper is installed at different positions.

[0025] In this embodiment, the displacement time history data includes all peak values, logarithmic decay rates and attenuation coefficients during the vibration attenuation process of the main beam after the vertical simple harmonic load is unloaded; the kth peak value of the vibration attenuation section of the main beam after the vertical simple harmonic load is unloaded is recorded as , the k+nth peak value is recorded as , where n is the number of wave peaks, and the additional damping ratio of the main beam is recorded as The logarithmic decay rate is denoted as , the attenuation coefficient is denoted as ; Through the second formula , and the additional damping ratio of the main beam is obtained.

[0026] Further, in one embodiment, a vertical simple harmonic load is applied at the peak displacement of the vertical vibration mode of the main beam, which includes the following steps: obtaining the vertical natural frequency of the main beam at the target damper at the target installation position, that is, the second natural frequency, denoted as ω n ; Let the vertical simple harmonic load be P, the excitation load amplitude be F, and the loading time be t; according to , vertical simple harmonic load is continuously applied to the peak of the vertical vibration mode displacement of the main beam, where , N is the number of natural vibration periods, which is adjusted based on the main beam vibration data.

[0027] In this embodiment, the vertical natural frequency of the main beam, that is, the second natural frequency, is obtained. The main beam is loaded according to the time , and then let F=0, the cable 2 is in a free vibration state, and the vertical simple harmonic load is continuously applied to the main beam bridge deck according to the set frequency, so that the entire subsequent vibration attenuation process can be analyzed and the displacement time history data can be obtained.

[0028] Furthermore, in one embodiment, the modal analysis includes the following: extracting the first three vibration modes of each cable and the fundamental frequency vibration mode of the main beam, and quantifying the vibration amplitude distribution of the main beam under different frequency excitations through harmonic response analysis.

[0029] In this embodiment, it is stipulated that the modal analysis needs to extract the first three vibration modes of the inclined cable and the fundamental frequency vibration mode of the main beam, and quantify the vibration amplitude distribution of the main beam under different frequency excitations through harmonic response analysis; the first three modes of the inclined cable are extracted to avoid missed judgments caused by only optimizing the first-order mode, and the harmonic response analysis can quantify the vibration amplitude of the main beam at a specific frequency; the frequency response characteristics of the damper can be customized through the harmonic response analysis results; the overlapping area between the high-order modes of the inclined cable and the fundamental frequency of the main beam is identified to avoid resonance risks when optimizing the installation position.

[0030] Furthermore, in one embodiment, the analysis of the vibration coupling effect is achieved in the following manner: modally superimposing the vibration mode of the main beam and the vibration mode of the inclined cable to identify the resonance risk area; calculating the energy transfer coefficient between the main beam and the inclined cable, and selecting the inclined cable with an energy transfer coefficient greater than the first standard value as the priority optimization target.

[0031] In this embodiment, the vibration coupling effect is specified, and the resonance area is identified through modal superposition to avoid the limitations of single structure optimization; the energy transfer coefficient is screened, such as >0.5, to quickly locate the inclined cables that contribute greatly to the overall vibration; the transmission of the main beam vibration to the inclined cables is reduced, and the reverse excitation of the inclined cable vibration on the main beam is suppressed, thereby achieving bidirectional vibration reduction; avoid equal optimization of all inclined cables, saving calculation and construction costs.

[0032] Furthermore, in one embodiment, before the vibration reduction method of the cable-stayed cables and main beams based on the damper installation position is implemented, an on-site environmental vibration test is performed on the cable-stayed bridge to obtain actual vibration spectrum data, and the finite element model is corrected based on the actual vibration spectrum data.

[0033] In this embodiment, it is required to conduct an on-site environmental vibration test before implementing the vibration reduction method to obtain actual vibration spectrum data, and to correct the boundary conditions of the finite element model accordingly; the corrected finite element model is more in line with the actual bridge characteristics, ensuring the reliability of subsequent damper position optimization; the measured spectrum data contains actual environmental excitations, so that the model can simulate real working conditions; through regular on-site testing and model correction, the dynamic characteristics changes caused by bridge aging or damage can be tracked, the vibration reduction plan can be dynamically adjusted, and construction rework due to model errors can be avoided.

[0034] Furthermore, in one embodiment, the external damper is a part of the inclined cable damper device 1, and the inclined cable damper device 1 also includes a support 3, a connecting member 4 and a main lever 5. The connecting member 4 is used to connect to the inclined cable 2, one end of the main lever 5 is fixedly connected to the connecting member 4, and the other end is rotatably connected to the support 3; the target damper is respectively connected to the upper and lower ends of the main lever 5.

[0035] In this embodiment, when the inclined cable 2 vibrates in the plane, since the inclined cable 2 is connected to the connecting member 4, the in-plane vibration will be transmitted to the connecting member 4. Since one end of the main lever 5 is fixedly connected to the connecting member 4, the in-plane vibration will be transmitted to the main lever 5 by the connecting member 4. The target damper is connected to the upper end of the main lever 5, and when there is in-plane vibration on the main lever 5, the target damper will absorb the in-plane vibration. In addition, when the inclined cable 2 vibrates out-of-plane, since the inclined cable 2 is connected to the connecting member 4, the out-of-plane vibration will be transmitted to the connecting member 4. Since one end of the main lever 5 is fixedly connected to the connecting member 4, the out-of-plane vibration will be transmitted to the main lever 5 by the connecting member 4. Since the target damper is connected to the lower end of the main lever 5, when there is out-of-plane vibration on the main lever 5, the target damper will absorb the out-of-plane vibration. At the same time, the connecting member 4 is connected to the inclined cable 2 to transfer the vibration of the inclined cable 2 to the connecting member 4, and the connecting member 4 is connected to the main lever 5 to transfer the vibration to the main lever 5. The target damper is connected to the upper end of the main lever 5 to absorb the in-plane vibration of the main lever 5; the target damper is connected to the lower end of the main lever 5 to absorb the out-of-plane vibration of the main lever 5. The present application can absorb in-plane vibration and out-of-plane vibration.

[0036] Further, in one embodiment, the target damper includes an in-plane damper 6, an in-plane lever 7, an out-of-plane damper 8, an out-of-plane lever 9, and an out-of-plane link 10; a first ear plate 31, a second ear plate 32 and a third ear plate 33 are provided on the support 3; the in-plane damper 6 is rotatably connected to the second ear plate 32, the middle part of the in-plane lever 7 is rotatably connected to the main lever 5, one end of the in-plane lever 7 is rotatably connected to the first ear plate 31, and the other end is connected to the in-plane damper 6; the out-of-plane damper 8 is rotatably connected to the middle part of the main lever 5, one end of the out-of-plane link 10 is rotatably connected to the bottom of the main lever 5, one end of the out-of-plane lever 9 is rotatably connected to the out-of-plane link 10, the other end of the out-of-plane lever 9 is rotatably connected to the out-plane damper 8, and the middle part of the out-of-plane lever 9 is rotatably connected to the third ear plate 33.

[0037] In this embodiment, when the inclined cable 2 vibrates in the plane, the vibration displacement of the inclined cable 2 is transmitted to the in-plane lever 7 through the connecting member 4, and then transmitted to the in-plane damper 6 to achieve vertical vibration reduction. The relative vibration displacement transmitted to the inside of the damper is amplified through the lever amplification mechanism, thereby improving the vertical damping vibration reduction efficiency; when the inclined cable 2 vibrates out of the plane, the vibration displacement of the inclined cable 2 is transmitted to the out-of-plane link rod 10 through the connecting member 4, and then transmitted to the out-of-plane lever 9 through the out-of-plane link rod 10, and then transmitted to the out-of-plane damper 8 to achieve lateral vibration reduction. Vibration reduction, through the lever amplification mechanism, amplifies the relative vibration displacement transmitted to the inside of the damper, thereby improving the lateral damping vibration reduction efficiency; when the main beam vibrates vertically, the vibration response of each part of the main beam will transmit the vertical vibration displacement to the in-plane damper 6 inside each inclined cable damper through the base 3, realizing the vertical vibration reduction energy dissipation of the main beam; when the main beam or the damper vibrates, due to the energy dissipation effect of the damper, the vibration response of the inclined cable 2 or the main beam can be reduced, thereby reducing the energy input at the excitation end and reducing the parameter vibration response.

[0038] Furthermore, in one embodiment, the included angle between the cable damper device 1 and the cable 2 is 90°.

[0039] In this way, at an angle of 90°, the damper body 11 can effectively transmit the force directly to the inclined cable 2 through the force transmission rod 12. This design perpendicular to the cable line can maximize the ability of the damper body 11 to absorb and dissipate vibration energy; when the inclined cable damper device 1 is perpendicular to the inclined cable 2, it can more effectively limit the propagation of vibration during the vibration reduction process, especially for lateral vibration, its damping effect is more significant. By adjusting the damping parameters of the damper, its response capacity at a specific frequency can be further optimized.

[0040] The beneficial effects brought by the present invention include: A vibration reduction method for cables and main beams based on the installation position of dampers is provided. By establishing finite element models of the main beam and cables and performing modal analysis on them, the vibration modes of each cable and the vibration response characteristics of the main beam are obtained, the dynamic characteristics of the structure are revealed, and data support is provided for subsequent optimization. The vibration modes of the cables and the vibration response characteristics of the main beam are combined to analyze the vibration coupling effect between the two. The interaction area between the cables and the main beam is identified through modal superposition and energy transfer coefficient calculation to avoid global resonance problems caused by local vibration. The standard installation range is set based on the vibration energy concentration area. The quantitative calculation of the additional damping ratio ensures the accuracy of position optimization, and the optimal installation position is independently determined for each cable, and the external damper is uniformly installed. The vibration sensitive area is accurately located through the finite element model and modal analysis, and the quantitative calculation of the additional damping ratio is combined to avoid the blindness of the traditional empirical method and maximize the energy absorption efficiency of the damper. The vibration coupling effect analysis ensures that the installation of the damper not only suppresses the local vibration of the cable, but also reduces the resonance risk of the main beam and the cable, thereby improving the dynamic stability of the overall structure. Through the closed-loop process of "modeling, analysis, optimization, and implementation", theoretical calculations are closely integrated with engineering practice, the problem of optimizing the damper installation position is solved, and the problem of how to determine the installation position of the external damper between each inclined cable and the main beam in the relevant technology is solved to most effectively reduce the vibration of the main beam and the inclined cable.

[0041] It should be noted that the serial numbers of the above-mentioned embodiments of the present application are only for description and do not represent the advantages or disadvantages of the embodiments.

[0042] The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings 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 limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices. The terms "first", "second" and "third" are used to distinguish different objects, etc., and do not represent a sequence, nor do they limit "first", "second" and "third" to different types.

[0043] In the description of the embodiments of the present application, "exemplary", "for example" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary", "for example" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary", "for example" or "for example" is intended to present related concepts in a specific way.

[0044] In the description of the embodiments of the present application, unless otherwise specified, “ / ” means or, for example, A / B can mean A or B; the “and / or” in the text is merely a description of the association relationship of associated objects, indicating that three relationships may exist, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, “multiple” refers to two or more than two.

[0045] In some processes described in the embodiments of the present application, multiple operations or steps that appear in a specific order are included, but it should be understood that these operations or steps may not be executed in the order in which they appear in the embodiments of the present application or in parallel, and the sequence number of the operation is only used to distinguish the different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed in sequence or in parallel, and these operations or steps may be combined.

[0046] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, disk, CD) as described above, and includes a number of instructions for a terminal device to execute the methods described in each embodiment of the present application.

[0047] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A vibration reduction method for a cable and a main beam based on the installation position of a damper, characterized in that: It includes: Establish finite element models of the main beam and each inclined cable, and perform modal analysis on them to obtain the vibration modes of each inclined cable and the vibration response characteristics of the main beam; For the target cable, based on its vibration mode and the vibration response characteristics of the main beam, the vibration coupling effect between the cable and the main beam is analyzed, and the standard installation range of the external damper set between the target cable and the main beam is determined; In the standard installation range, by adjusting the position of the external damper, the additional damping ratio of the main beam at different positions is calculated in combination with the vibration amplitude change of the main beam, and the maximum value of the additional damping ratio of the main beam is selected as the target installation position; According to the step of determining the target installation position of the target inclined cable, the target installation position corresponding to the external damper set between each inclined cable and the main beam is obtained, and the external damper is set between each inclined cable and the main beam according to the corresponding target installation position.

2. The vibration reduction method of the cable and main beam based on the damper installation position according to claim 1, characterized in that: The length of the cable is recorded as L, the connection point between the cable and the bridge deck is recorded as point M, and the distance between the connection point between the target damper and the target cable and point M is recorded as x, then the first threshold range is defined as: A={x|0.005L<x≤0.05L}; The value falling within the first threshold range in the standard installation interval of each inclined-stayed cable is obtained, and updated as the standard installation interval of the corresponding inclined-stayed cable.

3. The vibration reduction method of the cable and main beam based on the damper installation position according to claim 1, characterized in that: In the standard installation range, by adjusting the position of the external damper and combining the vibration amplitude change of the main beam, the additional damping ratio of the main beam at different positions is calculated, which includes the following steps: Based on the vibration response characteristics of the main beam, the peak value of the vertical vibration mode displacement of the main beam with the external damper located at the target installation position is obtained; Combined with the finite element model, a vertical simple harmonic load is applied at the peak displacement of the vertical vibration mode of the main beam, and then the vertical simple harmonic load is unloaded, and the vibration attenuation process of the main beam is analyzed to obtain the displacement time history data; According to the displacement time history data, the additional damping ratio of the main beam is calculated by a second formula; Repeat the above steps to obtain the additional damping ratio of the main beam when the external damper is installed at different positions.

4. The vibration reduction method of the cable and main beam based on the damper installation position according to claim 3, characterized in that: Applying a vertical simple harmonic load at the peak of the vertical vibration mode displacement of the main beam includes the following steps: Obtain the vertical natural frequency of the main beam with the target damper at the target installation position, that is, the second natural frequency, denoted as ω n ; The vertical simple harmonic load is denoted as P, the excitation load amplitude is denoted as F, and the loading time is denoted as t; according to , vertical simple harmonic load is continuously applied to the peak of the vertical vibration mode displacement of the main beam, where , N is the number of natural vibration periods, which is adjusted based on the main beam vibration data.

5. The vibration reduction method of the cable and main beam based on the damper installation position according to claim 1, characterized in that: Modal analysis includes the following: The first three vibration modes of each cable and the fundamental frequency vibration mode of the main beam are extracted, and the vibration amplitude distribution of the main beam under different frequency excitations is quantified through harmonic response analysis.

6. The vibration reduction method of the cable and main beam based on the damper installation position according to claim 1, characterized in that: The analysis of the vibration coupling effect is achieved in the following way: Perform modal superposition of the vibration modes of the main beam and the stay cable to identify the resonance risk area; The energy transfer coefficient between the main beam and the inclined cable is calculated, and the inclined cables with energy transfer coefficients greater than the first standard value are selected as priority optimization targets.

7. The vibration reduction method of the cable and main beam based on the damper installation position according to claim 1, characterized in that: Before the vibration reduction method of the cable-stayed cable and the main beam based on the damper installation position is implemented, an on-site environmental vibration test is performed on the cable-stayed bridge to obtain actual vibration spectrum data, and the finite element model is corrected based on the actual vibration spectrum data.

8. The vibration reduction method of the cable and main beam based on the damper installation position according to claim 1, characterized in that: The external damper is a part of a cable-stayed damper device (1), and the cable-stayed damper device (1) further comprises a support (3), a connecting member (4), and a main lever (5), wherein the connecting member (4) is used to be connected to the cable (2), and one end of the main lever (5) is fixedly connected to the connecting member (4), and the other end is rotatably connected to the support (3); The target damper is connected to the upper end and the lower end of the main lever (5) respectively.

9. The vibration reduction method of the cable and main beam based on the damper installation position according to claim 8, characterized in that: The target damper comprises an in-plane damper (6), an in-plane lever (7), an out-of-plane damper (8), an out-of-plane lever (9), and an out-of-plane link rod (10); The support (3) is provided with a first ear plate (31), a second ear plate (32) and a third ear plate (33); The in-plane damper (6) is rotatably connected to the second ear plate (32), the middle portion of the in-plane lever (7) is rotatably connected to the main lever (5), one end of the in-plane lever (7) is rotatably connected to the first ear plate (31), and the other end is connected to the in-plane damper (6); The out-of-plane damper (8) is rotationally connected to the middle part of the main lever (5), one end of the out-of-plane link rod (10) is rotationally connected to the bottom of the main lever (5), one end of the out-of-plane lever (9) is rotationally connected to the out-of-plane link rod (10), the other end of the out-of-plane lever (9) is rotationally connected to the out-of-plane damper (8), and the middle part of the out-of-plane lever (9) is rotationally connected to the third ear plate (33).

10. The vibration reduction method of the cable and main beam based on the damper installation position according to claim 8, characterized in that: The included angle between the stay cable damper device (1) and the stay cable (2) is 90°.

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