Low-frequency adjustable mass damper for bridge

Abstract

The invention relates to the technical field of bridge vibration control, and discloses a low-frequency adjustable mass damper for a bridge, which comprises a bracket, a mass block and a plurality of vibration suppression elements. The multiple deformation parts in the vibration suppression element are constructed to be sequentially arranged in the direction away from the mass block in the horizontal direction, and meanwhile the connecting parts are arranged, so that the multiple deformation parts capable of independently generating vertical deformation are connected into a whole in a series connection mode; on the basis of ensuring that the vibration suppression element can be matched with the mass block to reliably absorb and dissipate vibration energy, the length of the vibration suppression element in the vertical direction can be effectively reduced, and therefore the size of the whole TMD in the vertical direction can be reduced. Meanwhile, the mass of the mass block is set to be adjustable, so that the TMD can reliably adapt to vibration frequency changes possibly generated in different construction stages of the bridge, and it is ensured that the vibration suppression effect of the TMD is good.

Description

Technical Field

[0001] The invention relates to the technical field of bridge vibration control, and in particular to a low-frequency adjustable frequency mass damper for a bridge. Background Art

[0002] The contents in this section merely provide background information related to the present invention and may not constitute prior art.

[0003] For long-span cable-stayed bridges constructed using the cantilever construction method, since such bridges have lower structural stiffness and lower natural vibration frequency, they are susceptible to wind loads such as typhoons during the construction period and produce greater buffeting responses. In order to ensure the safety of such bridges during the construction period, it is necessary to control the buffeting response of the bridge during the construction period.

[0004] Currently, a common method for controlling the buffeting response of a long-span cable-stayed bridge during construction includes setting a tuned mass damper (TMD). Summary of the invention

[0005] However, the inventors of the present invention have found that the currently known tuned mass dampers are often only applicable to small and medium span bridges with high vibration frequencies, such as pedestrian overpasses, scenic landscape bridges, etc. In addition, in these tuned mass dampers, the springs used in the tuned mass dampers to cooperate with the mass block to absorb and dissipate vibration energy often adopt a single-root design. With regard to this design, in order to provide a larger travel space to adapt to the vibration amplitude changes that may occur during the bridge construction process, it is often necessary to design the elongation of the single spring to be long enough, which invisibly increases the volume of the overall structure of the tuned mass damper in the vertical direction. At the same time, due to the different stages of bridge construction, the vibration frequency of the bridge structure will also change, and the total mass of the known tuned mass damper is difficult to adjust, so that it cannot adapt to the vibration frequency changes that may occur in the bridge at different construction stages.

[0006] In view of this, an object of the present invention is to provide a low frequency adjustable mass damper for a bridge, so as to at least overcome the above-mentioned problems existing in the known tuned mass damper.

[0007] The purpose of the present invention is achieved through the following technical solutions:

[0008] The invention discloses a low-frequency adjustable frequency mass damper for a bridge, comprising:

[0009] A bracket defines a receiving space;

[0010] A mass block is elastically held in the accommodation space; the mass of the mass block is adjustable;

[0011] A plurality of vibration damping elements, the plurality of vibration damping elements being arranged circumferentially of the mass block; one end of each vibration damping element is connected to the mass block, and the other end of the vibration damping element is fixed; the vibration damping element includes:

[0012] A plurality of deformation parts, the plurality of deformation parts being sequentially arranged in a direction away from the mass block in the horizontal direction, and each deformation part can undergo vertical deformation;

[0013] A connecting part is provided between two adjacent deformation parts; the connecting part is configured to connect two adjacent deformation parts so that the two adjacent deformation parts can undergo vertical deformation synchronously.

[0014] Further, the connecting part includes a guide wheel set and a traction rope, the guide wheel set is fixedly arranged, one end of the traction rope is connected to the corresponding end of one of the two adjacent deformation parts, and the other end of the traction rope is connected to the corresponding end of the other of the two adjacent deformation parts after passing around the guide wheel set;

[0015] One end of the deformation part close to the mass block that is not connected to the corresponding traction rope is connected to the mass block, and one end of the deformation part far from the mass block that is not connected to the corresponding traction rope is fixed.

[0016] Further, the deformation part is a pre-tensioned spring.

[0017] Further, both the mass block and the bracket are provided with hanging rings corresponding to each vibration damping element;

[0018] One end of the deformation part close to the mass block in each vibration damping element is detachably connected to the corresponding hanging ring on the mass block, and one end of the deformation part far from the mass block in each vibration damping element is detachably connected to the corresponding hanging ring on the bracket.

[0019] Further, the mass block includes a hanging basket, the hanging basket defines an upwardly open placement cavity, and the placement cavity is adapted to accommodate a plurality of removable counterweight blocks.

[0020] Further, a connecting plate is provided on the outer circumferential wall of the hanging basket, and a reinforcing rib is provided between the connecting plate and the outer wall of the hanging basket.

[0021] Further, the natural vibration frequency of the deformation part is equal to the first-order vertical vibration frequency of the bridge.

[0022] Further, the bracket is made of Q355 steel.

[0023] Further, the plurality of vibration damping elements are equally divided into two groups, and the two groups of vibration damping elements are respectively arranged on opposite sides of the mass block;

[0024] The vibration suppression elements in each group of the vibration suppression elements are arranged in a line along the outer edge of the mass block.

[0025] Furthermore, the bracket includes a top frame, a bottom frame, and a plurality of connecting columns;

[0026] The top frame and the bottom frame are arranged opposite to each other in the vertical direction, the plurality of connecting columns are arranged between the top frame and the bottom frame, and both ends of each connecting column are respectively connected to the top frame and the bottom frame;

[0027] The top frame, the bottom frame, and the plurality of connecting columns jointly enclose to form the accommodation space.

[0028] The technical solution of the embodiment of the present invention has at least the following advantages and beneficial effects:

[0029] 1. For the low-frequency adjustable tuned mass damper for bridges disclosed in the present invention, by configuring a plurality of deformation parts in the vibration suppression element to be arranged in sequence in the horizontal direction away from the mass block, and at the same time by setting the connecting part, it is realized that a plurality of deformation parts capable of independently undergoing vertical deformation are connected into a whole in series, and the plurality of deformation parts in the vibration suppression element can undergo vertical deformation synchronously. On the basis of ensuring that the vibration suppression element can cooperate with the mass block to reliably absorb and dissipate vibration energy, the length of the vibration suppression element in the vertical direction can be effectively reduced, thereby helping to reduce the volume of the entire TMD in the vertical direction.

[0030] 2. In the present invention, by setting the mass of the mass block to be adjustable, when the bridge is under construction at different stages and the vibration frequency of the bridge changes, the total mass of the entire TMD can be adjusted by adjusting the mass of the mass block, so that the TMD can reliably adapt to the vibration frequency changes that may occur in different construction stages of the bridge, ensuring good vibration suppression effect of the TMD. Description of the Drawings

[0031] Figure 1 It is a schematic structural diagram of a low-frequency adjustable tuned mass damper for bridges provided by an embodiment of the present invention;

[0032] Figure 2 is Figure 1 a top view of the low-frequency adjustable tuned mass damper for bridges shown in

[0033] Figure 3 is Figure 2 a cross-sectional view taken along the A-A direction in , which shows the case where the vibration suppression element includes two deformation parts;

[0034] Figure 4Schematic diagram of the support structure provided by an embodiment of the present invention;

[0035] Figure 5 Schematic diagram of the vibration suppression element including two deformation parts provided by an embodiment of the present invention;

[0036] Figure 6 Schematic diagram of the mass block provided by an embodiment of the present invention;

[0037] Figure 7 is Figure 3 Enlarged view of the local structure at position B in

[0038] Figure 8 Partial structure cross-sectional view of another embodiment of the low-frequency adjustable mass damper for a bridge provided by an embodiment of the present invention, which shows the case where the vibration suppression element includes three deformation parts.

[0039] Icon: 10 - support, 11 - top frame, 12 - bottom frame, 13 - connecting column, 20 - mass block, 21 - hanging basket, 22 - placement cavity, 23 - connecting plate, 24 - reinforcing rib, 30 - vibration suppression element, 31 - deformation part, 32 - connecting part, 321 - guide wheel set, 322 - towing rope, 40 - lifting ring. Detailed implementation manners

[0040] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the detailed implementation manners. The same reference numerals in the drawings represent the same components. It should be noted that the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the described embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0041] Compared with the embodiments shown in the drawings, the feasible implementation solutions within the scope of protection of the present invention may have fewer components, have other components not shown in the drawings, different components, differently arranged components or differently connected components, etc. In addition, two or more components in the drawings may be implemented in a single component, or a single component shown in the drawings may be implemented as multiple separate components.

[0042] An embodiment of the present invention discloses a low-frequency adjustable mass damper for a bridge, which is used to control the buffeting response during the bridge construction period. By optimizing the design of the spring and the mass block 20, the low-frequency adjustable mass damper can reliably adapt to the vibration frequency changes that may occur in different construction stages of the bridge on the basis of simplifying the structural design of the mass damper. For the convenience of description, the low-frequency adjustable mass damper disclosed in the embodiments of the present invention will be abbreviated as TMD hereinafter.

[0043] As shown Figure 1 in the figure, it shows the external shape of the exemplary TMD disclosed in the embodiments of the present invention. In Figure 1 the TMD shown, the TMD may include a bracket 10, a mass block 20, and a plurality of vibration damping elements 30.

[0044] Combined with Figures 1 to 4 the content shown, the bracket 10 may be a steel frame generally in a rectangular shape to define an accommodation space s for accommodating the mass block 20 inside the bracket 10.

[0045] Furthermore, the bracket 10 may include a top frame 11, a bottom frame 12, and a plurality of connecting columns 13. Both the top frame 11 and the bottom frame 12 may have a generally rectangular shape, and the top frame 11 and the bottom frame 12 are arranged opposite to each other in the vertical direction. The plurality of connecting columns 13 are disposed between the top frame 11 and the bottom frame 12, and both ends of each connecting column 13 are respectively connected to the top frame 11 and the bottom frame 12. In this way, the accommodation space s can be formed by jointly enclosing the top frame 11, the bottom frame 12, and the plurality of connecting columns 13.

[0046] Exemplarily, in the drawings of this embodiment, a case where the bracket 10 includes four connecting columns 13 is shown, and the four corners of the top frame 11 and the bottom frame 12 are respectively connected by a connecting column 13 to optimize the structural design of the bracket 10 as much as possible.

[0047] Combined with Figure 1 and Figure 3 the content shown, the mass block 20 is elastically held in the accommodation space s of the bracket 10 under the combined action of the plurality of vibration damping elements 30, and the mass block 20 located in the accommodation space s has at least degrees of freedom in the vertical direction, that is, the mass block 20 can at least move freely in the accommodation space s in the vertical direction. Among them, the function of the mass block 20 is to provide a counterweight for the entire TMD so that the total mass of the TMD meets the use requirements.

[0048] Moreover, the mass of the mass block 20 is adjustable. It should be noted that by setting the mass of the mass block 20 in an adjustable form, when the bridge is under construction at different stages, causing the vibration frequency of the bridge to change, the total mass of the entire TMD can be adjusted by adjusting the mass of the mass block 20, so that the TMD can reliably adapt to the vibration frequency changes that may occur at different construction stages of the bridge and ensure good vibration damping effect of the TMD.

[0049] In this embodiment, in addition to elastically holding the mass block 20 in the accommodation space s of the bracket 10, the plurality of vibration damping elements 30 are also used to cooperate with the mass block 20 when the bridge undergoes buffeting to absorb and dissipate vibration energy.

[0050] Specifically, in combination with Figure 1 and Figure 3 as shown, a plurality of vibration damping elements 30 can be arranged circumferentially around the mass block 20.

[0051] For a single vibration damping element 30, one end of the vibration damping element 30 is connected to the mass block 20, and the other end of the vibration damping element 30 is fixed to provide an elastic force to the mass block 20 to elastically hold the mass block 20 within the accommodation space s.

[0052] Referring to Figure 3 or Figure 8 as shown, each vibration damping element 30 can include a plurality of deformation portions 31. The plurality of deformation portions 31 are sequentially arranged in the horizontal direction away from the mass block 20. That is, in the direction away from the mass block 20, the horizontal distance between the plurality of deformation portions 31 and the mass block 20 increases in sequence. Each deformation portion 31 can undergo vertical deformation.

[0053] Moreover, a connecting portion 32 is provided between two adjacent deformation portions 31. The connecting portion 32 is used to connect two adjacent deformation portions 31 so that two adjacent deformation portions 31 can undergo vertical deformation synchronously. In this way, the plurality of deformation portions 31 in a single vibration damping element 30 can undergo vertical deformation synchronously.

[0054] It should be noted that the vertical deformation described in this embodiment refers to the deformation along the vertical direction. Among them, the deformation portion 31 described in this embodiment can be a spring arranged along the vertical direction so that the deformation portion 31 can undergo vertical deformation.

[0055] Based on the above settings, when the bridge undergoes buffeting and transmits the vibration energy to the TMD, the vibration energy can be absorbed and dissipated under the combined action of the plurality of vibration damping elements 30 of the TMD and the mass block 20. Specifically, for a single vibration damping element 30, based on one end of the vibration damping element 30 being connected to the mass block 20, the other end of the vibration damping element 30 being fixed, and the plurality of deformation portions 31 in the vibration damping element 30 being able to undergo vertical deformation synchronously, the vertical movement of the mass block 20 can be driven through the vertical deformation of the plurality of deformation portions 31, thereby realizing the absorption and dissipation of the vibration energy. And, for a single vibration damping element 30, before absorbing and dissipating the vibration energy, or during the process of absorbing and dissipating the vibration energy, the plurality of deformation portions 31 always maintain a parallel state with each other.

[0056] It is worth noting that, in this embodiment, by configuring the multiple deformation parts 31 in the vibration suppression element 30 to be arranged in sequence in the horizontal direction in the direction away from the mass block 20, and by providing the connecting part 32, the multiple deformation parts 31 that can independently undergo vertical deformation are connected in series into a whole, and the multiple deformation parts 31 in the vibration suppression element 30 can undergo vertical deformation synchronously. On the basis of ensuring that the vibration suppression element 30 can cooperate with the mass block 20 to reliably absorb and dissipate vibration energy, when the travel space provided by the vibration suppression element 30 is large so that the elongation required by the vibration suppression element 30 is large, the total elongation required by the vibration suppression element 30 can be equally divided into the deformation parts 31 (that is, the deformation parts 31 have the same elongation). Compared with the conventional method of providing a spring extending in the vertical direction to absorb and dissipate vibration energy in the prior art, the length of the vibration suppression element 30 in the vertical direction can be effectively reduced, thereby helping to reduce the volume of the entire TMD in the vertical direction.

[0057] For example, assuming that the total elongation required of the vibration suppression element 30 is 10.2 m, if a spring extending in the vertical direction is arranged in the conventional manner in the prior art, it is not only not conducive to implementation, but also the spring will have a long length, so that the volume of the TMD formed by it in the vertical direction is large. On the contrary, in this embodiment, the total elongation required of the vibration suppression element 30 can be equally divided into each deformation part 31, so that each deformation part 31 has a smaller length, which is conducive to implementation and can effectively reduce the volume of the TMD formed by the vibration suppression element 30 in the vertical direction. For example, using the solution disclosed in this embodiment, when the deformation part 31 is Figure 3 In the two cases shown in FIG. 1 , it is only necessary to control the elongation of each deformation portion 31 to about 5.1 m, so that the total elongation of the vibration suppression element 30 can reach 10.2 m; or, when the deformation portion 31 is Figure 8 In the three cases shown, the total elongation of the vibration suppression element 30 can reach 10.2 m by only controlling the elongation of each deformation portion 31 to about 3.4 m.

[0058] The vibration suppression element 30 may be further constructed in the following manner but is not limited thereto, so that a plurality of deformation portions 31 sequentially arranged in the horizontal direction in the vibration suppression element 30 are connected in series with each other and can synchronously undergo vertical deformation.

[0059] Specifically, combined Figure 3 and Figure 5As shown, the connecting portion 32 may include a guide wheel set 321 and a traction rope 322. The guide wheel set 321 is fixedly arranged, for example, fixed on the bracket 10. One end of the traction rope 322 is connected to the corresponding end of one of the adjacent two deformation portions 31, and the other end of the traction rope 322 is connected to the corresponding end of the other deformation portion 31 after passing around the guide wheel set 321. One end of the deformation portion 31 close to the mass block 20 that is not connected to the corresponding traction rope 322 is connected to the mass block 20, such as the top outer edge of the mass block 20; one end of the deformation portion 31 far from the mass block 20 that is not connected to the corresponding traction rope 322 is fixed, for example, fixedly connected to the bracket 10.

[0060] For example, referring to Figure 3 or Figure 8 As shown, assume that the deformation portion 31 close to the mass block 20 is defined as the 1st deformation portion 31, and the remaining deformation portions 31 are defined as the 2-Nth deformation portions 31 in the direction away from the mass block 20, where N≥2. Then: the bottom end of the 1st deformation portion 31 is connected to the mass block 20, one end of the traction rope 322 between the 1st and 2nd deformation portions 31 is connected to the top end of the 1st deformation portion 31, the other end of the traction rope 322 between the 1st and 2nd deformation portions 31 is connected to the top end of the 2nd deformation portion 31 after passing around the corresponding guide wheel set 321. At this time, the guide wheel set 321 between the 1st and 2nd deformation portions 31 can be fixed on the top frame 11 of the bracket 10; one end of the traction rope 322 between the 2nd and 3rd deformation portions 31 is connected to the bottom end of the 2nd deformation portion 31, the other end of the traction rope 322 between the 2nd and 3rd deformation portions 31 is connected to the bottom end of the 3rd deformation portion 31 after passing around the corresponding guide wheel set 321. At this time, the guide wheel set 321 between the 2nd and 3rd deformation portions 31 can be fixed on the bottom frame 12 of the bracket 10; and so on; one end of the Nth deformation portion 31 that is not connected to the corresponding traction rope 322 is fixed. Among them, whether the fixed end of the Nth deformation portion 31 is the top end or the bottom end of the deformation portion 31 depends on the number of deformation portions 31. Specifically, when the number of deformation portions 31 is even (that is, Figure 3 the two shown in Figure 8 ), the 2nd deformation portion 31, as the deformation portion 31 far from the mass block 20, its own bottom end is fixed, for example, fixedly connected to the bottom frame 12 of the bracket 10; correspondingly, when the number of deformation portions 31 is odd (that is, Figure 8 the three shown in Figure 8 ), the 3rd deformation portion 31, as the deformation portion 31 far from the mass block 20, its own top end is fixed, for example, fixedly connected to the top frame 11 of the bracket 10.

[0061] It can be understood that by using the towing rope 322 that bypasses the guide pulley group 321 to connect two adjacent deformation parts 31, not only are multiple deformation parts 31 connected in series, enabling the multiple deformation parts 31 to undergo vertical deformation synchronously, but also the connecting part 32 composed of the towing rope 322 and the guide pulley group 321 has at least the advantages of simple structure, easy implementation, high reliability, and strong durability.

[0062] In this embodiment, each deformation part 31 in the vibration damping element 30 can further be, for example, Figure 5 the pre-tension spring as shown. It can be understood that by using the pre-tension spring as the deformation part 31, before the vibration damping element 30 plays the role of absorbing and dissipating vibration energy, part of the tensile amount of the deformation part 31 under the action of the initial load (such as the gravity of components such as the mass block 20) can be eliminated, which helps to further reduce the elongation amount required for each deformation part 31 and enables the TMD to suppress vibration reliably within a smaller stroke range.

[0063] Combined with Figure 6 and Figure 7 As shown in the figure, suspension rings 40 corresponding to each vibration damping element 30 can also be provided on the mass block 20 and the bracket 10. Among them, the deformation part 31 of each vibration damping element 30 close to the mass block 20 is detachably connected to the corresponding suspension ring 40 on the mass block 20, and the deformation part 31 of each vibration damping element 30 far from the mass block 20 is detachably connected to the corresponding suspension ring 40 on the bracket 10. For example, in the case where the deformation part 31 is a pre-tension spring, the deformation part 31 close to the mass block 20 can be hooked to the corresponding suspension ring 40 on the mass block 20 by means of its own hook, and the deformation part 31 far from the mass block 20 can be hooked to the corresponding suspension ring 40 on the bracket 10 by means of its own hook. In this way, it is beneficial to the quick disassembly and assembly of the vibration damping element 30.

[0064] Referring to Figure 1 As shown in the figure, multiple vibration damping elements 30 can also be equally divided into two groups, and the two groups of vibration damping elements 30 are respectively arranged on opposite sides of the mass block 20, and the vibration damping elements 30 in each group of vibration damping elements 30 can be arranged in a straight line along the outer edge of the mass block 20. For example, in the drawings of this embodiment, a situation where the TMD includes 16 vibration damping elements 30 is shown. At this time, the 16 vibration damping elements 30 can be equally divided into two groups, each group of vibration damping elements 30 includes 8 vibration damping elements 30, the two groups of vibration damping elements 30 are respectively arranged on opposite sides of the mass block 20, and the 8 vibration damping elements 30 in each group of vibration damping elements 30 are arranged in a straight line along the outer edge of the mass block 20. In this way, it not only helps to further optimize the structural design of the TMD, but also can evenly distribute the vibration energy by using multiple vibration damping elements 30, avoiding the occurrence of local stress concentration and further improving the vibration damping effect of the TMD.

[0065] Among them, the mass of the mass block 20 can be adjusted in the following ways, but not limited to them.

[0066] Specifically, in combination with Figure 6 As shown in the figure, the mass block 20 includes a hanging basket 21 in a box structure, and the hanging basket 21 defines a placement cavity 22 that opens upward. Among them, the placement cavity 22 on the hanging basket 21 is adapted to accommodate a plurality of removable counterweight blocks (not shown in the figure). For example, cast iron with a certain mass (such as 20 kg) can be used as the counterweight block. In this way, when it is necessary to adjust the mass of the mass block 20, only the number of counterweight blocks in the placement cavity 22 needs to be increased or decreased as required, and the operation is simple and convenient.

[0067] Furthermore, a horizontal connecting plate 23 can be provided on the outer circumferential wall of the hanging basket 21, and a triangular reinforcing rib 24 can be provided between the connecting plate 23 and the outer wall of the hanging basket 21. Among them, the lifting ring 40 provided on the mass block 20 can be provided on the connecting plate 23.

[0068] Through the above settings, the shear resistance of the box-structured hanging basket 21 can be effectively improved to ensure the safety of the TMD under strong winds as much as possible, and reduce the risk of slip or offset of the hanging basket 21 caused by wind vibration. And the hanging basket 21 can be made of corrosion-resistant high-strength steel, such as 316 stainless steel, so that it can reliably adapt to complex environments such as high humidity and high salt in coastal areas, effectively improving the durability and safety of the hanging basket 21.

[0069] In addition, the inventors of the present invention further studied and showed that the structural design of the bracket 10 is crucial for ensuring the vibration suppression effect and structural safety of the TMD. Specifically, the bracket 10 not only needs to bear the weight of the mass block 20, but also must meet the requirements of vibration frequency matching. For this reason, when designing the TMD, software such as ANSYS can be used to analyze the internal forces and deformations of the bracket 10 under different working conditions to ensure that the bracket 10 can work stably and reliably under complex wind environments and construction loads.

[0070] The inventors of the present invention studied and showed that by controlling the maximum deformation of the bracket 10 within 9.46 mm, the stress of the cross-section of the bracket 10 can also meet the design requirements, and it can ensure that the TMD has a good vibration suppression effect in a high-intensity buffeting environment.

[0071] In addition, another important objective of the design of the support 10 is to ensure the height and stability of the overall structure of the TMD, so that the TMD can fully exert its vibration suppression function within a limited space. To cope with the strong wind buffeting that may occur when the bridge is in the maximum cantilever state during strong wind periods such as typhoon periods, the support 10 must be designed with high stiffness to prevent the vibration of the support 10 itself from reducing the vibration suppression effect. For this purpose, the support 10 in this embodiment can be made of high-strength steel, such as Q355 steel, and combined with the stress and deformation analysis described above, so as to control the overall weight and installation height of the support 10 while ensuring the wind resistance effect.

[0072] In addition, the design of the support 10 also particularly considers the operability of the construction environment, ensuring that it can be safely and stably installed and operated near the cantilever end of the bridge, and facilitating the quick adjustment of the mass block 20 during the construction process. In terms of the optimization of the structural design, the height of the support 10 is controlled within 5.5 meters to ensure stable support within a limited construction space.

[0073] On the other hand, in the vibration suppression element 30 of the TMD, the design of the spring as the deformation part 31 aims to ensure that the TMD is consistent with or close to the main vibration frequency of the bridge to achieve the best vibration suppression effect. For example, in a certain cross-sea cable-stayed bridge, the first-order vertical vibration frequency of the bridge is about 0.1559 Hz. To enable the TMD to effectively suppress the vertical vibration of the bridge, the natural vibration frequency of the deformation part 31 in the vibration suppression element 30 must also be adjusted to be consistent with or close to the first-order vertical vibration frequency of the bridge, that is, the natural vibration frequency of the deformation part 31 can be equal to the first-order vertical vibration frequency of the bridge to achieve frequency matching.

[0074] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A low frequency adjustable mass damper for a bridge, characterized in that: include: A bracket defines a receiving space; A mass block is elastically held in the accommodation space; The mass of the mass block is adjustable; A plurality of vibration suppression elements, wherein the plurality of vibration suppression elements are arranged in a circumferential direction of the mass block; One end of the vibration suppression element is connected to the mass block, and the other end of the vibration suppression element is fixed; The vibration suppression element comprises: A plurality of deformation parts, wherein the plurality of deformation parts are arranged in sequence in a horizontal direction away from the mass block, and each of the deformation parts can undergo vertical deformation; A connecting portion is provided between two adjacent deformation portions; the connecting portion is configured to connect the two adjacent deformation portions so that the two adjacent deformation portions can synchronously undergo vertical deformation.

2. The low frequency adjustable mass damper for bridges according to claim 1, characterized in that: The connecting part comprises a guide wheel group and a traction rope, wherein the guide wheel group is fixedly arranged, one end of the traction rope is connected to an end corresponding to one of the two adjacent deformation parts, and the other end of the traction rope is connected to an end corresponding to the other of the two adjacent deformation parts after passing through the guide wheel group; An end of the deformation portion close to the mass block that is not connected to the corresponding traction rope is connected to the mass block, and an end of the deformation portion far from the mass block that is not connected to the corresponding traction rope is fixed.

3. The low frequency adjustable mass damper for bridges according to claim 1 or 2, characterized in that: The deformation part is a pre-tension spring.

4. The low frequency adjustable mass damper for bridges according to claim 1, characterized in that: The mass block and the bracket are both provided with hanging rings corresponding to the vibration suppression elements one by one; The deformation portion of each vibration suppression element close to the mass block is detachably connected to the corresponding suspension ring on the mass block, and the deformation portion of each vibration suppression element far from the mass block is detachably connected to the corresponding suspension ring on the bracket.

5. The low frequency adjustable mass damper for bridges according to claim 1, characterized in that: The mass block comprises a hanging basket, which defines an upwardly open placement cavity, and the placement cavity is suitable for accommodating a plurality of removable counterweight blocks.

6. The low frequency adjustable mass damper for bridges according to claim 5, characterized in that: A connecting plate is provided on the circumferential outer wall of the hanging basket, and a reinforcing rib is provided between the connecting plate and the outer wall of the hanging basket.

7. The low frequency adjustable mass damper for bridges according to claim 1, characterized in that: The natural frequency of the deformation part is equal to the first-order vertical vibration frequency of the bridge.

8. The low frequency adjustable mass damper for bridges according to claim 1, characterized in that: The bracket is made of Q355 steel.

9. The low frequency adjustable mass damper for bridges according to claim 1, characterized in that: The plurality of vibration suppression elements are equally divided into two groups, and the two groups of vibration suppression elements are respectively arranged on two opposite sides of the mass block; The vibration suppression elements in each group of the vibration suppression elements are arranged in a line along the outer edge of the mass block.

10. The low frequency adjustable mass damper for bridges according to claim 1, characterized in that: The bracket includes a top frame, a bottom frame and a plurality of connecting columns; The top frame and the bottom frame are arranged opposite to each other in the vertical direction, the plurality of connecting columns are arranged between the top frame and the bottom frame, and two ends of each connecting column are connected to the top frame and the bottom frame respectively; The top frame, the bottom frame and the plurality of connecting columns together enclose the accommodation space.

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