Vibration control structure for a bridge pier

Abstract

The present application provides a kind of vibration control structure of bridge pier, the vibration control structure of bridge pier, at least two layers of damper are arranged, each layer of damper has multiple, and the height of the damper of same layer from ground is same, can be equivalent modal mass same, damping effect is similar.Different layers of damper height from ground is different, equivalent modal mass is different, damping effect is different.The number of damping mounting frame can have multiple, the height of different layers of damping mounting frame from ground is different, equivalent modal mass is different, and the damping effect generated by each other is different.Thereby, by changing the number of damping mounting frame and the height of each damping mounting frame from ground, equivalent modal mass can be changed, avoid damping effect single, realize flexible damping.

Description

Technical Field

[0001] This invention relates to the field of vibration control technology, and in particular to a vibration control structure for bridge piers. Background Technology

[0002] With the increasing haulage of existing railway bridges and the rise in railway transport volume, the axle load of individual trains has been continuously increased, train traction quality has been continuously improved, and the speed of existing lines has been significantly increased, along with the increasing traffic density. This has led to a significant improvement in railway transport capacity and economic efficiency. However, the coupling phenomenon between trains and bridges has become increasingly prominent, causing the lateral vibration amplitude of bridge piers to continuously increase, even exceeding the limits specified in the standards. Excessive vibration of bridge piers can cause damage, greatly increasing the workload of bridge maintenance personnel, requiring more staff, and increasing maintenance costs. It can also raise concerns among train drivers about bridge safety, affecting driving comfort. To further improve the transport capacity of heavy-haul railways and ensure the balance and safety of heavy-haul railway lines and bridges, it is necessary to combine the actual needs of railway bridge vibration reduction with applied research on bridge vibration reduction technology, develop suitable vibration reduction devices, and apply them to actual bridges to achieve the goal of bridge vibration reduction and ensure the safe operation of railway bridges.

[0003] Lateral vibration of railway bridges is a highly complex engineering problem. When a train passes over a bridge, the additional weight of the train further reduces the bridge's vibration frequency, and trains with different loads will excite vibrations at different frequencies. However, existing vibration damping structures used on bridges typically have the same equivalent modal mass, resulting in a single vibration reduction effect and a lack of flexibility in vibration reduction. Summary of the Invention

[0004] Therefore, it is necessary to provide a vibration control structure for bridge piers to address the aforementioned technical problems.

[0005] A vibration control structure for a bridge pier includes a damping mounting frame and a damper as described in any of the above embodiments. The damping mounting frame includes at least a first mounting frame and a second mounting frame arranged adjacent to each other. The first mounting frame and the second mounting frame are stacked along the vertical height direction. The first mounting frame is equipped with at least one of the dampers, and the second mounting frame is equipped with at least one of the dampers.

[0006] In one embodiment, the damping mounting bracket is disposed along the edge of the pier cap platform and is erected on the pier cap platform.

[0007] In one embodiment, each of the damping mounting brackets is symmetrically arranged on both sides of the pier cap platform.

[0008] In one embodiment, the dampers of the first mounting bracket and the dampers of the second mounting bracket are provided in a one-to-one correspondence.

[0009] In one embodiment, the dampers on the first mounting bracket are mounted at the same height, and the dampers on the second mounting bracket are mounted at the same height.

[0010] In one embodiment, the damper includes a top plate, a bottom plate, an outer cylinder, an inner cylinder, and a weight; the outer cylinder is sleeved outside the inner cylinder, one end of the outer cylinder is connected to the top plate, and the other end of the outer cylinder is connected to the bottom plate; one end of the inner cylinder is connected to the top plate, and the other end of the inner cylinder is connected to the bottom plate; a receiving cavity is formed between the top plate, the bottom plate, the outer cylinder, and the inner cylinder; the weight is disposed in the receiving cavity; and the distance between the weight and the top plate is set according to the control frequency.

[0011] In one embodiment, the distance between the weight block and the top plate is less than the distance between the weight block and the bottom plate; or, the distance between the weight block and the bottom plate is less than the distance between the weight block and the top plate; or, the distance between the weight block and the bottom plate is equal to the distance between the weight block and the top plate.

[0012] In one embodiment, the damper further includes a connector traction member and a fixing device, one end of the connector traction member being installed inside the inner cylinder and the other end being connected to the fixing device.

[0013] In one embodiment, the weight block is spaced apart from the base plate, forming a bottom buffer cavity between the weight block and the base plate, the bottom buffer cavity accommodating a bottom buffer member; and / or,

[0014] The weight block is spaced apart from the top plate, and a top buffer cavity is formed between the weight block and the top plate, which accommodates the top buffer component.

[0015] In one embodiment, the bottom buffer includes at least one of a buffer solution and a rolling element;

[0016] The top buffer includes at least one of a buffer solution and a rolling element.

[0017] The vibration control structure of the aforementioned bridge piers incorporates at least two layers of dampers. Each layer contains multiple dampers, and dampers within the same layer are at the same height above the ground, resulting in identical equivalent modal masses and similar vibration reduction effects. Dampers in different layers are at different heights above the ground, leading to different equivalent modal masses and varying vibration reduction effects. Multiple damping mounting frames can be used, with different heights above the ground for each layer, resulting in different equivalent modal masses and varying vibration reduction effects. It's important to understand that since the damping mounting frames are stacked vertically, their heights above the ground will differ. Therefore, by changing the number of damping mounting frames and their heights above the ground, the equivalent modal mass can be altered, avoiding a single vibration reduction effect and achieving flexible vibration reduction. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the damper structure in one embodiment;

[0019] Figure 2 This is a schematic diagram of the damper in another embodiment;

[0020] Figure 3 This is a schematic diagram of the damper in another embodiment;

[0021] Figure 4 This is a schematic diagram of the damper in another embodiment;

[0022] Figure 5 This is a schematic diagram of the damper in another embodiment;

[0023] Figure 6 This is a schematic diagram of the damper in another embodiment;

[0024] Figure 7 This is a schematic diagram of the damper in another embodiment;

[0025] Figure 8 This is a schematic diagram of the damper in another embodiment;

[0026] Figure 9 This is a schematic diagram of the damper in another embodiment;

[0027] Figure 10 This is a schematic diagram of the vibration control structure for a bridge pier in one embodiment;

[0028] Figure 11 This is a schematic diagram of the vibration control structure of the bridge pier in another embodiment;

[0029] Figure 12 This is a schematic diagram of the layout of the damping mounting bracket in one embodiment.

[0030] Reference numerals: 10, damper; 110, top plate; 120, bottom plate; 130, outer cylinder; 140, inner cylinder; 150, weight block; 160, accommodating cavity; 161, bottom buffer cavity; 162, top buffer cavity; 163, buffer solution; 164, buffer component; 170, connecting traction component; 180, fixing fixture; 181, mounting through hole; 190, zinc-aluminum casting layer; 20, damping mounting bracket; 20A, first mounting bracket; 20B, second mounting bracket; 30, pier cap platform. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0032] Example 1

[0033] In this embodiment, as Figure 10 As shown, a vibration control structure for a bridge pier is provided, including a damping mounting frame 20 and a damper 10 as described in any of the above embodiments. The damping mounting frame 20 includes at least a first mounting frame 20A and a second mounting frame 20B arranged adjacent to each other. The first mounting frame 20A and the second mounting frame 20B are stacked along the vertical height direction. At least one damper 10 is mounted on the first mounting frame 20A, and at least one damper 10 is mounted on the second mounting frame 20B. In this embodiment, to achieve a better vibration reduction effect, at least two layers of dampers 10 are provided. Each layer has multiple dampers 10, and the dampers 10 in the same layer are at the same height from the ground, which can result in the same equivalent modal mass and similar vibration reduction effect. The dampers 10 in different layers are at different heights from the ground, resulting in different equivalent modal masses and different vibration reduction effects. The number of damping mounting frames 20 can be multiple, and the damping mounting frames 20 in different layers are at different heights from the ground, resulting in different equivalent modal masses and different vibration reduction effects. Therefore, the equivalent modal mass can be changed by altering the number of damping mounting brackets 20 and the height of each damping mounting bracket 20 from the ground, thus avoiding a single vibration reduction effect and achieving flexible vibration reduction.

[0034] like Figure 11 As shown, in one embodiment, the damping mounting bracket 20 is arranged along the edge of the pier cap platform 30, and the damping mounting bracket 20 is erected on the pier cap platform 30. In this embodiment, in order to better achieve the vibration reduction effect on the bridge, the damping mounting bracket 20 is arranged along the edge of the pier cap platform 30, so that dampers 10 are present in different directions along the edge of the pier cap platform 30 to reduce vibration.

[0035] like Figure 11As shown, in one embodiment, each of the damping mounting brackets 20 is symmetrically arranged on both sides of the pier cap platform 30. In this embodiment, dampers 10 are respectively installed on both sides of the pier cap platform 30 to reduce vibration and enhance the vibration reduction effect.

[0036] like Figure 11 As shown, in one embodiment, the dampers 10 of the first mounting frame 20A and the dampers 10 of the second mounting frame 20B are arranged in a one-to-one correspondence. In this embodiment, in order to facilitate the determination of the vibration reduction effect of each layer, the dampers 10 of the first mounting frame 20A and the dampers 10 of the second mounting frame 20B are arranged in a one-to-one correspondence, that is, the layout of the dampers 10 of the two layers is the same, and each damper 10 of the first mounting frame 20A has a corresponding damper 10 of the second mounting frame 20B in the vertical direction.

[0037] like Figure 11 As shown, in one embodiment, the dampers 10 on the first mounting bracket 20A are mounted at the same height, and the dampers 10 on the second mounting bracket 20B are mounted at the same height. In this embodiment, in order to make the damping effect of the dampers 10 in the same layer similar, the dampers 10 in the same layer are set at the same height.

[0038] like Figure 11 As shown, furthermore, the lengths of the coupling traction members 170 of each damper 10 in the first mounting frame 20A are the same, and / or, the lengths of the coupling traction members 170 of each damper 10 in the second mounting frame 20B are the same. In this embodiment, to facilitate control of the height of each damper 10, the coupling traction members 170 of the dampers 10 in the same layer are set to the same length, which facilitates adjustment of the position of each damper 10 in the same layer. Furthermore, the lengths of the coupling traction members 170 of the dampers 10 in the first mounting frame 20A are the same as the lengths of the coupling traction members 170 of the dampers 10 in the second mounting frame 20B.

[0039] like Figure 11 As shown, further, the outer cylinders 130 of each damper 10 in the first mounting bracket 20A have the same height, and / or, the outer cylinders 130 of each damper 10 in the second mounting bracket 20B have the same height. In this embodiment, to facilitate control of the height of each damper 10, the outer cylinders 130 of the dampers 10 in the same layer are set to the same height, which facilitates adjustment of the position of each damper 10 in the same layer. Further, the height of the outer cylinders 130 of the dampers 10 in the first mounting bracket 20A is the same as the height of the outer cylinders 130 of the dampers 10 in the second mounting bracket 20B.

[0040] like Figure 11As shown, in one embodiment, the number of dampers 10 in the first mounting bracket 20A is the same as the number of dampers 10 in the second mounting bracket 20B. In this embodiment, to facilitate control of the vibration reduction effect, the number of dampers 10 in both layers is set to be the same, making it easier to determine the vibration reduction effect of each damper 10.

[0041] like Figure 12 As shown, in one embodiment, the height of the first mounting bracket 20A is a first height, the height of the second mounting bracket 20B is a second height, and the height of the pier cap is the pier height; the equivalent modal mass of the damper 10 of the first mounting bracket 20A is... The equivalent modal mass of the damper 10 of the second mounting bracket 20B is: Where H is the pier height, h1 is the first height, and h2 is the second height. In this embodiment, in order to achieve a better vibration reduction effect, the first mounting bracket 20A and the second mounting bracket 20B are set on the pier cap platform 30, raising the position of the damper 10, raising the displacement transmission point, and improving the equivalent modal mass, resulting in a better vibration reduction effect. A lighter mass can be used to achieve a better vibration reduction effect, reducing the mass required for the damper 10 and reducing the manufacturing cost of the damper 10.

[0042] See Figures 1 to 7 In one embodiment, the damper 10 includes a top plate 110, a bottom plate 120, an outer cylinder 130, an inner cylinder 140, and a weight block 150. The outer cylinder 130 is sleeved outside the inner cylinder 140. One end of the outer cylinder 130 is connected to the top plate 110, and the other end of the outer cylinder 130 is connected to the bottom plate 120. One end of the inner cylinder 140 is connected to the top plate 110, and the other end of the inner cylinder 140 is connected to the bottom plate 120. A receiving cavity 160 is formed between the top plate 110, the bottom plate 120, the outer cylinder 130, and the inner cylinder 140. The weight block 150 is disposed in the receiving cavity 160, and the distance between the weight block 150 and the top plate 110 is set according to the control frequency.

[0043] In this embodiment, the control frequency of the damper 10 can be achieved by adjusting the distance between the weight block 150 and the top plate 110. Since the weight block 150 is located inside the damper 10, the appearance of the damper 10 remains unchanged when the position of the weight block 150 changes, while the control frequency of the damper 10 can be different. See also Figure 8 and Figure 9 Specifically, the control frequency of the damper 10 is determined according to equation (1), which is shown below:

[0044]

[0045] In equation (1), f is the damper control frequency in Hz; m is the mass of the mass block, m = m1 + m2 in kg; and K is the bending stiffness of the steel strand in N / m. See also Figure 9 and Figure 10 The mass block includes the top plate 110, bottom plate 120, outer cylinder 130, inner cylinder 140, and weight block 150. m1 includes the mass of the top plate 110, bottom plate 120, outer cylinder 130, and inner cylinder 140, and m2 includes the weight of weight block 150. The formula for calculating the bending stiffness K of the steel strand is shown in formula (2):

[0046]

[0047] Where E is the elastic modulus of the steel strand, 2 × 10¹¹ N / m²; J is the moment of inertia of the steel strand, in m⁴; L is the length of the steel strand, calculated as L = l + (m₁·Y / ² + m₂·y) / (m₁ + m₂), in meters, based on the center position relationship; n is the number of steel strands. Y is the cylinder height, i.e., the height of the outer cylinder 130, and y is the distance from the center of gravity of the mass block to the top plate 110. l represents the length of the steel strand between the top plate 110 and the clamp.

[0048] It should be understood that the control frequency of the damper 10 can be adjusted by changing the distance between the center of gravity of the mass block and the top plate 110, and the control frequency of the damper 10 can also be adjusted by adjusting the parameters in formula (1) and formula (2).

[0049] like Figures 3 to 5 As shown, in one embodiment, the distance between the weight block 150 and the top plate 110 is less than the distance between the weight block 150 and the bottom plate 120; or, the distance between the weight block 150 and the bottom plate 120 is less than the distance between the weight block 150 and the top plate 110; or, the distance between the weight block 150 and the bottom plate 120 is equal to the distance between the weight block 150 and the top plate 110. In this embodiment, the weight block 150 can be positioned close to the top plate 110, or it can be positioned between the top plate 110 and the bottom plate 120, or it can be positioned close to the bottom plate 120, so that the control frequency of the damper 10 changes.

[0050] like Figures 6 to 7As shown, in one embodiment, the damper 10 further includes a connector traction member 170 and a fixing device 180. One end of the connector traction member 170 is fixedly installed inside the inner cylinder 140, and the other end is connected to the fixing device 180. In this embodiment, to facilitate the installation of the damper 10 into the desired application scenario, the connector traction member 170 is connected to the inner cylinder 140, and the fixing device 180 connected to the other end of the connector traction member 170 is fixed to the object where the damper 10 is to be used, such as a bridge or a tall building. When the bridge or tall building sways, the damper 10 sways accordingly to reduce the degree of swaying of the bridge or tall building.

[0051] In one embodiment, the fixing device 180 is a fixing clamp that clamps and connects the connector traction member 170. In this embodiment, to facilitate the connection between the fixing device 180 and the connector traction member 170, the fixing device 180 is configured as a fixing clamp to clamp and fix the connector traction member 170.

[0052] In one embodiment, the fixing fixture 180 includes a fixture cast from a zinc-aluminum alloy. In this embodiment, the zinc-aluminum alloy is a conventional zinc-aluminum alloy, and no material modification is made. Due to the excellent machinability of zinc-aluminum alloy, the cast-molded fixing fixture 180 is easy to process and form.

[0053] like Figures 6 to 7 As shown, in one embodiment, the fixing device 180 has a mounting through hole 181. In this embodiment, in order to facilitate the connection of the fixing device 180 to bridges and tall buildings, a mounting through hole 181 is provided on the fixing device 180, so that fasteners such as bolts can pass through the mounting through hole 181 to install the damper 10 on the bridges and tall buildings.

[0054] In one embodiment, the traction member 170 includes galvanized steel strand. In this embodiment, damping is provided by the friction of the steel wires inside the strand. The galvanized steel strand has high strength and is not easily broken, allowing it to better bear the weight of the inner cylinder 140, outer cylinder 130, weight block 150, top plate 110, and bottom plate 120.

[0055] In one embodiment, the number of galvanized steel strands in the connector traction member 170 may include one, two, or more. In this embodiment, the load-bearing capacity of the connector traction member 170 can be flexibly controlled by adjusting the number of galvanized steel strands.

[0056] In one embodiment, the connector traction member 170 is cast into the inner cylinder 140. In this embodiment, in order to strengthen the connection between the connector traction member 170 and the inner cylinder 140, the connector traction member 170 is cast into the inner cylinder 140, so that the connector traction member 170 fully penetrates into the inner cylinder 140 for connection, thereby strengthening the connection.

[0057] like Figure 9 As shown, in one embodiment, a zinc-aluminum alloy is cast between the connector traction member 170 and the inner cylinder 140 to form a zinc-aluminum casting layer 190. In this embodiment, to strengthen the connection between the connector traction member 170 and the inner cylinder 140, a zinc-aluminum alloy is used for casting. The zinc-aluminum alloy has good fluidity and can fully penetrate the gap between the connector traction member 170 and the inner cylinder 140. In one embodiment, in formula (1), m1 also includes the mass of the zinc-aluminum alloy cast between the connector traction member 170 and the inner cylinder 140. In this embodiment, to make the calculation of the control frequency more accurate, m1 also includes the mass of the zinc-aluminum alloy cast between the connector traction member 170 and the inner cylinder 140, fully considering the influence of the mass of each component in the damper 10 on the control frequency. In another embodiment, cement is cast between the connector traction member 170 and the inner cylinder 140 to form a cement casting layer.

[0058] like Figures 3 to 5 As shown, in one embodiment, the weight block 150 is spaced apart from the base plate 120, and a bottom buffer cavity 161 is formed between the weight block 150 and the base plate 120, the bottom buffer cavity 161 accommodating a bottom buffer member 164; and / or, the weight block 150 is spaced apart from the top plate 110, and a top buffer cavity 162 is formed between the weight block 150 and the top plate 110, the top buffer cavity 162 accommodating a top buffer member 164. In this embodiment, in order to enable the damper 10 to better reduce the sway of the bridge, a bottom buffer member 164 is provided in the bottom buffer cavity 161 between the weight block 150 and the base plate 120, so that when the damper 10 sways with the bridge, the bottom buffer member 164 sways, buffering the sway amplitude of the damper 10, providing cushioning for the bridge, and reducing the sway amplitude of the bridge. Similarly, a top buffer 164 is provided in the bottom buffer cavity 161 between the weight block 150 and the top plate 110, so that when the damper 10 sways with the bridge, the top buffer 164 sways, thus buffering the swaying amplitude of the damper 10.

[0059] like Figures 1 to 2As shown, in one embodiment, the bottom buffer 164 includes at least one of a buffer solution 163 and a rolling element; the top buffer 164 includes at least one of a buffer solution 163 and a rolling element. In this embodiment, in order to better achieve the sway amplitude of the damper 10, the bottom buffer 164 selects at least one of a buffer solution 163 and a rolling element to buffer the sway of the damper 10, and the top buffer 164 selects at least one of a buffer solution 163 and a rolling element to buffer the sway of the damper 10. The buffer solution 163 can sway in the bottom buffer cavity 161 and the top buffer cavity 162, and the rolling element can roll in the bottom buffer cavity 161 and the top buffer cavity 162 to buffer the sway of the damper 10.

[0060] In one embodiment, the buffer solution 163 includes at least one of silicone oil and mineral oil. In this embodiment, silicone oil is non-volatile, which prevents the buffer solution 163 from evaporating at high ambient temperatures, thus avoiding affecting the swaying effect of the buffer solution 163 damper 10. Mineral oil is cheaper, which can reduce the manufacturing cost of the damper 10. Due to its viscous properties, mineral oil flows slowly, effectively reducing kinetic energy and improving buffering performance.

[0061] In one embodiment, the rolling element includes at least one of a ball and a roller. In this embodiment, to better buffer the swaying of the damper 10, a ball or roller is selected as the rolling element. The rolling of the ball and roller is more flexible and can better buffer the swaying of the damper 10. The surface of the ball or roller is conducive to buffering the impact force at different angles. The outer circumference of the roller is annular, which can buffer the impact force in a 360-degree circumferential direction and disperse the force in different directions, which helps to improve the buffering effect. In addition, in the buffer solution 163, the kinetic energy in a certain direction can be converted into rotational kinetic energy by rotation, which drives the buffer solution 163 to tumble. The tumbling of the buffer solution 163 effectively dissipates the impact force in a certain direction.

[0062] like Figures 1 to 2 As shown, in one embodiment, the bottom buffer 164 and the top buffer 164 are the same. In this embodiment, in order to better reduce the swaying of the damper 10, the bottom buffer 164 and the top buffer 164 are the same, that is, the bottom buffer 164 and the top buffer 164 are made of the same material, so that the degree and rhythm of cushioning at the upper and lower ends of the counterweight 150 are similar, resulting in a better cushioning effect.

[0063] like Figures 1 to 2As shown, in one embodiment, the volume of the bottom buffer cavity 161 is the same as the volume of the top buffer cavity 162. In this embodiment, in order to make the swaying of the damper 10 more regular, the volumes of the bottom buffer cavity 161 and the top buffer cavity 162 are set to be the same, so that the bottom buffer cavity 161 and the top buffer cavity 162 can accommodate the same number of buffer members 164, so that the buffering degree of the upper and lower ends of the weight block 150 is similar, resulting in a better vibration reduction effect.

[0064] In one embodiment, the inner side of the weight block 150 is sealed to the inner cylinder 140, and the outer side of the weight block 150 is sealed to the outer cylinder 130. The height of the outer cylinder 130 is the same as the height of the inner cylinder 140. One end of the outer cylinder 130 is aligned with one end of the inner cylinder 140, and the other end of the outer cylinder 130 is aligned with the other end of the inner cylinder 140. The top plate 110 and the bottom plate 120 are respectively planar. The top plate 110 is sealed to one end of the outer cylinder 130 and one end of the inner cylinder 140, and the bottom plate 120 is sealed to the other end of the outer cylinder 130 and the other end of the inner cylinder 140. In this embodiment, the components around the bottom buffer cavity 161 and the top buffer cavity 162 are connected in a sealed manner to seal the bottom buffer cavity 161 and the top buffer cavity 162, thereby reducing the degree of contact between the sealed bottom buffer component 164 and the top buffer component 164 and the external environment, and preventing the bottom buffer component 164 and the top buffer component 164 from oxidizing or leaking, which would affect the vibration reduction effect.

[0065] In one embodiment, the inner cylinder 140 is welded to the bottom plate 120; and / or, the inner cylinder 140 is welded to the top plate 110; and / or, the inner cylinder 140 is welded to the weight block 150. In this embodiment, to facilitate the connection between the components of the damper 10, the inner cylinder 140 is welded to the bottom plate 120, the top plate 110, and the weight block 150 respectively, which reduces the manufacturing difficulty of the damper 10.

[0066] In one embodiment, the outer cylinder 130 is welded to the bottom plate 120; and / or, the outer cylinder 130 is welded to the top plate 110; and / or, the outer cylinder 130 is welded to the weight block 150. In this embodiment, to facilitate the connection between the components of the damper 10, the outer cylinder 130 is welded to the bottom plate 120, the top plate 110, and the weight block 150 respectively, which reduces the manufacturing difficulty of the damper 10.

[0067] In one embodiment, the inner cylinder 140 and the outer cylinder 130 are cylindrical, and the bottom buffer cavity 161 and the top buffer cavity 162 are annular. In this embodiment, in order to achieve vibration reduction in all directions from 0 degrees to 360 degrees, the inner cylinder 140 and the outer cylinder 130 are cylindrical, and the bottom buffer cavity 161 and the top buffer cavity 162 are annular, so that the damper 10 can produce the same vibration reduction effect in all directions.

[0068] like Figures 3 to 5 As shown, in one embodiment, the weight block 150 is annular, with the inner side of the weight block 150 connected to the inner cylinder 140 and the outer side of the weight block 150 connected to the outer cylinder 130. In this embodiment, to better achieve an all-around vibration reduction effect, the weight block 150 is set in an annular shape, and the swaying effect of the weight block 150 is the same in all directions, so that the damper 10 can better achieve vibration reduction in all directions from 0 degrees to 360 degrees.

[0069] Example 2

[0070] In this embodiment, as Figures 10 to 12 As shown, a vibration control structure for a bridge pier is provided. The damper 10 is arranged on the pier cap platform 30 via a frame and supported by a multi-layered support system. It is positioned along the edge of the pier cap, replacing the existing railing. The pier height is H, the lower support height is h1, the upper support height is h2, and so on. The modal mass M of the pier and structure is M1, the lower TMD modal mass is M1, the upper TMD modal mass is M2, and so on. In this case, the lower TMD has an equivalent modal mass due to the raised displacement transmission point caused by the frame. The upper-layer TMD has an increased displacement transfer point due to the raised frame, resulting in an equivalent modal mass. And so on. It can be seen that the equivalent modal mass of the TMD can be increased by adjusting the frame height, resulting in better vibration reduction. A lighter mass can be used to achieve better vibration reduction.

[0071] In one embodiment, the steps for controlling the lateral vibration of railway beam bridge piers are as follows:

[0072] Step 1: Based on the transverse vibration control objectives of railway beam bridge piers, such as the control frequency (or frequency range) and the conversion relationship between the control effect and the mode participation coefficient, determine the required total moving mass M of the damper, the control frequency f (or frequency range), and the damping ratio ξ.

[0073] In step 1, the conversion relationship between control frequency (or frequency range), control effect, and modal participation factor refers to the conversion relationship between the three parameters: control frequency, control effect, and modal participation factor. The total mass M is determined by the required control effect of the structure, generally taken as 0.5% to 5% of the modal mass of the controlled structure. The control frequency refers to the frequency of the TMD being basically consistent with the frequency of the controlled structure; there is generally a frequency ratio relationship, ranging from 0.95 to 1.0, with a larger mass ratio resulting in a smaller frequency ratio. The damping ratio is a parameter of the TMD itself, which needs to be determined through parameter optimization; the optimal damping ratio differs for different mass ratios of the TMD. In this embodiment, the damping ratio can be adjusted by adjusting the number of steel wires in the steel strand.

[0074] Step 2: Discretize the damper into n smaller dampers, determine the mass of each smaller damper as m, M = nm, and control the frequency f (or frequency range) and damping ratio ξT.

[0075] In step 2, based on the classical TMD vibration reduction theory, the modal mass ratio μ of the TMD and the sling is selected for parameter optimization by gradually increasing the ratio. This corresponds to the optimal frequency ratio γ of the TMD and the sling being 1 / (1+μ), and the optimal damping ratio ξ of the TMD being... T = [3 / 8(1+μ)] 1 / 2 The optimization results are shown in Table 1. As can be seen from Table 1, the additional damping ratio provided by the TMD to the structure increases with the increase of the modal mass ratio. Under the optimal parameters of the TMD, a very small mass ratio (0.01%) can meet the vibration reduction requirements of the suspension cable (damping ratio greater than 0.5%).

[0076] Table 1 Optimization Results of Cable-TMD Optimal Parameters

[0077] Tab.1Optimal parameter optimization results of TMD-hangers

[0078]

[0079]

[0080] In step 2, the control frequencies of each small TMD can all be f, or they can be different, mainly depending on the controlled frequency of the main structure. If the main structure has a single control frequency, the TMD can have a single frequency; if the main structure has multiple control frequencies, the TMD can also take multiple control frequencies. Furthermore, by optimizing the TMD's output frequency to be discretized between 0.9 and 1.1f, the range of the TMD's control frequency f on the structure can be widened to the 0.9–1.1f range. The damping ratio of the small damper is mainly obtained through optimization of its own mass ratio to the structure, as shown in the relevant calculation formulas in the table above.

[0081] Step 3: Determine the required steel strand stiffness K of the damper based on the mass m of each small damper and the control frequency f (or frequency range).

[0082] Step 4: Based on the stiffness K of the steel strand, select the length L of the damper steel strand to ensure that the length of the steel strand of all types of dampers is consistent. First, determine the diameter and quantity of the steel strand.

[0083] Step 5: Determine the arrangement of the main beam based on the determined steel strand type, quantity, and mass of the mass blocks. The steel strand type includes the diameter of a single steel wire and the number of wires (7 wires or 19 wires, etc.), expressed as the diameter of a single steel strand.

[0084] Step 6: Place the support frame on the pier top platform and install the pendulum-type TMD.

[0085] Step 7: Verify the vibration reduction effect of the dampers before and after installation through on-site testing.

[0086] The pendulum-type TMD proposed in this embodiment is isotropic and can effectively control multi-directional structural vibrations. Compared with traditional TMDs, the pendulum-type TMD does not require external springs for stiffness or external damping devices for damping, and it does not require external frame support, resulting in high mass utilization and low space occupancy. The support structure's amplification effect effectively increases the modal mass ratio of the TMD, thereby reducing the mass of the TMD itself and its impact on the structure, leading to better vibration reduction. The damper's construction and frequency tuning method (all mass blocks have the same shape, and the control frequency is adjusted by the center of gravity of the mass blocks) are optimized. The support structure raises the damper's installation height, amplifying the TMD's modal mass and improving the vibration reduction effect. The steel strand mentioned in this embodiment can be made of other materials, such as reinforcing bars, steel wire ropes, or steel bars. While maintaining the same mass block shape, the zinc-aluminum alloy can be replaced with ultra-high performance concrete. This embodiment is not limited to lateral vibration control of bridge piers; longitudinal vibration control is also possible.

[0087] like Figure 1 and Figure 2 As shown, in one embodiment, the damper 10 includes: galvanized steel strands (single or multiple strands combined, providing damping through internal wire friction), steel strand clamps, and a mass block (the mass block consists of a top plate 110, a bottom plate 120, a stainless steel tube, and a thick-walled steel tube). The steel strand clamps are cast from zinc-aluminum alloy, with the upper clamps of the galvanized steel strands cast from zinc-aluminum alloy and pre-drilled through holes 181. The lower part of the galvanized steel strands is cast inside the stainless steel tube. The stainless steel tube is welded to the bottom plate 120, the top plate 110, and the annular thick-walled steel tube. The outer cylinder 130 steel tube is welded to the bottom plate 120, the top plate 110, and the thick-walled steel tube, forming a combined assembly with upper and lower cavities. The cavities can be filled with ball bearings for impact energy dissipation, or filled with liquid (such as silicone oil) for energy dissipation through liquid sloshing. This TMD design is simple in structure, requires no spring for stiffness, requires no additional damping energy dissipation device, and has a large equivalent mass.

[0088] In this embodiment, the thick-walled steel pipe is the weight block 150, the steel strand clamp is the fixing device 180, and the galvanized steel strand is the connector and traction component 170. The zinc-aluminum alloy is the component connecting the steel strand and the internal stainless steel pipe.

[0089] In one embodiment, the frequency adjustment of the damper 10 is set as follows: by adjusting the center position of the mass block to adjust the control frequency range, it can be ensured that the dampers 10 used have the same appearance but different control frequencies.

[0090] The single control frequency of the damper 10 in this embodiment can be adjusted by controlling the mass and distribution of the mass block, the number, diameter and length of the steel strands, etc. The control frequency calculation formula (1) is shown:

[0091]

[0092] Where f is the control frequency of the damper, Hz; m is the mass of the mass block, m = m1 + m2, kg; K is the bending stiffness of the steel strand, N / m;

[0093]

[0094] Where E is the elastic modulus of the steel strand, 2×10¹¹ N / m²; J is the moment of inertia of the steel strand, m⁴; L is the length of the steel strand, which, according to the center position relationship, is L=l+(m1·Y / 2+m2·y) / (m1+m2), in meters; n is the number of steel strands. Y is the cylinder height, and y is the distance from the center of gravity of the mass block to the top plate.

[0095] In this embodiment, the distribution of the mass blocks refers to the distance y from the center of gravity of the mass blocks to the top plate. m1 includes the mass of the top plate, bottom plate, outer cylinder, and stainless steel cylinder. m2 includes the mass of the thick-walled tube.

[0096] In existing technologies, tuned mass dampers (TMDs) typically consist of a mass block, a spring, and a damping device. TMDs have been successfully applied to control vibrations in engineering structures, such as wind-induced vibrations, earthquakes, and other forms of vibration. However, they suffer from frequency sensitivity, a single control direction, and the need for specialized damping and energy dissipation devices, such as viscous dampers, magnetorheological dampers, friction dampers, and eddy current dampers. Furthermore, the introduction of springs, damping devices, and other supporting components further increases the added mass and cost of the TMD, limiting its application in structural vibration reduction. To address the shortcomings of existing technologies, this embodiment proposes a pendulum-type tuned mass damper and its design method suitable for lateral vibration control of railway bridges, resolving the issues of cumbersome frequency adjustment, single control direction, and large added mass. This embodiment offers advantages such as convenient frequency adjustment, consistent damper appearance, and minimal added mass to the main structure. Furthermore, to address the deficiencies of existing tuned mass dampers, this embodiment proposes a lateral vibration control damper for bridge piers and its design method. This damper system has a simple structure, can control 360-degree vibration within a plane, adds little mass to the structure, and has excellent energy dissipation effect, providing good protection for engineering structures. This embodiment proposes a pendulum-type tuned mass damper where stiffness and damping are provided by steel strands and mass is provided by a mass block. The control frequency is adjusted by changing the center of gravity position of the mass block, resulting in different dominant control frequencies. Raising the support amplifies the damper's displacement and modal mass, leading to better vibration reduction.

Claims

1. A vibration control structure for bridge piers, characterized in that, The system includes a damping mounting frame and a damper. The damping mounting frame includes at least a first mounting frame and a second mounting frame arranged adjacent to each other. The first mounting frame and the second mounting frame are stacked along the vertical height direction. At least one damper is mounted on the first mounting frame, and at least one damper is mounted on the second mounting frame. The dampers on the same mounting frame are at the same height from the ground. The dampers on different mounting frames are at different heights from the ground and have different equivalent modal masses to match the different vibration frequencies of the bridge pier. The damper includes a top plate, a bottom plate, an outer cylinder, an inner cylinder, and a weight; the outer cylinder is sleeved outside the inner cylinder, one end of the outer cylinder is connected to the top plate, and the other end of the outer cylinder is connected to the bottom plate; one end of the inner cylinder is connected to the top plate, and the other end of the inner cylinder is connected to the bottom plate; a receiving cavity is formed between the top plate, the bottom plate, the outer cylinder, and the inner cylinder, and the weight is disposed in the receiving cavity; The distance between the weight block and the top plate is set according to the control frequency, and the control frequency of the damper is adjusted by changing the height position of the weight block in the accommodating cavity.

2. The vibration control structure for bridge piers according to claim 1, characterized in that, The damping mounting bracket is installed along the edge of the pier cap platform and is erected on the pier cap platform.

3. The vibration control structure for bridge piers according to claim 2, characterized in that, The damping mounting brackets are symmetrically arranged on both sides of the pier cap platform.

4. The vibration control structure for bridge piers according to claim 1, characterized in that, The dampers of the first mounting bracket and the dampers of the second mounting bracket are configured in a one-to-one correspondence.

5. The vibration control structure for bridge piers according to claim 4, characterized in that, The dampers on the first mounting bracket are installed at the same height, and the dampers on the second mounting bracket are installed at the same height.

6. The vibration control structure for bridge piers according to claim 1, characterized in that, The distance between the weight block and the top plate is less than the distance between the weight block and the bottom plate; or, the distance between the weight block and the bottom plate is less than the distance between the weight block and the top plate; or, the distance between the weight block and the bottom plate is equal to the distance between the weight block and the top plate.

7. The vibration control structure for bridge piers according to claim 1, characterized in that, The damper also includes a connector traction component and a fixing device. One end of the connector traction component is installed inside the inner cylinder, and the other end is connected to the fixing device.

8. The vibration control structure for bridge piers according to claim 1, characterized in that: The weight block is spaced apart from the base plate, forming a bottom buffer cavity between the weight block and the base plate, the bottom buffer cavity accommodating a bottom buffer component; and / or The weight block is spaced apart from the top plate, and a top buffer cavity is formed between the weight block and the top plate, which accommodates the top buffer component.

9. The vibration control structure for bridge piers according to claim 8, characterized in that: The bottom buffer includes at least one of a buffer solution and a rolling element; The top buffer includes at least one of a buffer solution and a rolling element.

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