Damping and amplifying device of damper for bridge

Abstract

A damping and amplifying device of a damper for a bridge belongs to the technical field of damping and amplifying devices of dampers, is arranged between a pier column and a beam body and comprises a horizontal supporting plate, one end of the horizontal supporting plate is fixedly connected with the pier column, the other end of the horizontal supporting plate extends along the trend of the beam body, and the bottom of the horizontal supporting plate is connected with the pier column through an inclined supporting rod. A seesaw device is arranged at the upper end of the horizontal supporting plate, the two ends of a plate body of the seesaw device are connected with the horizontal supporting plate through a first damper and a second damper respectively, the two ends of the plate body of the seesaw device are connected with the bottom of the beam body through flexible inhaul cables respectively, and the two flexible inhaul cables are arranged in a crossed mode. The energy dissipation and shock absorption effects of the damper can be remarkably improved, and therefore the anti-seismic performance of a bridge structure is further improved. Compared with an existing amplification device, the device has the advantages of being small in component section, small in occupied space and large in amplification coefficient.

Description

Technical Field

[0001] The present invention belongs to the technical field of damper shock absorption amplification devices, and particularly relates to a damper shock absorption amplification device for bridges. Background Art

[0002] Earthquakes are natural disasters with characteristics such as being difficult to predict and having strong destructive power. As a transportation hub, the seismic performance of bridges is crucial. In recent years, scholars at home and abroad have conducted extensive research on bridge shock absorption technology and achieved certain results. As an effective seismic measure, shock absorption amplification devices can play a certain role in enhancing the seismic performance of bridge projects. In the 1970s, the United States first carried out research on bridge shock absorption technology. Subsequently, countries such as Japan, Italy, and New Zealand also successively carried out relevant research. Foreign scholars have conducted a large number of theoretical analyses and experimental studies on shock absorption amplification devices and achieved fruitful results. The research on bridge shock absorption technology in China began in the 1980s. In recent years, with the country's emphasis on infrastructure construction, bridge shock absorption technology has developed rapidly. Domestic scholars have achieved remarkable results in shock absorption amplification devices. Currently, shock absorption devices that have been successfully applied to actual projects at home and abroad include: friction pendulum bearings, lead-core rubber bearings, high-damping rubber bearings, etc. Currently, when applying the above shock absorption devices in China, amplification devices are rarely used. Even when viscous dampers and other devices are set near the bearings, amplification devices are generally not set. Although researchers at home and abroad have studied amplification devices, many of the components used in amplification devices have too large cross-sectional dimensions or their amplification forms occupy too much space, which is not conducive to application in actual bridge projects. Summary of the Invention

[0003] In order to further enhance the shock absorption effect of the damper, the present invention proposes a damper shock absorption amplification device for bridges and gives a calculation formula for the amplification coefficient. This amplification device can significantly enhance the energy dissipation and shock absorption effect of the damper, thereby further enhancing the seismic performance of the bridge structure. Compared with existing amplification devices, the present invention has the characteristics of small component cross-sections, less space occupation, and a relatively large amplification coefficient.

[0004] To achieve the above object, the technical solution of the present invention is as follows:

[0005] A damper shock absorption amplification device for bridges, the amplification device is arranged between the pier column and the beam body, and includes a horizontal support plate with one end fixedly connected to the pier column and the other end extending along the direction of the beam body. The bottom of the horizontal support plate is connected to the pier column through an inclined support rod. A seesaw device is arranged at the upper end of the horizontal support plate. The two ends of the plate body of the seesaw device are respectively connected to the horizontal support plate through a first damper and a second damper. The two ends of the plate body of the seesaw device are respectively connected to the bottom of the beam body through flexible cables, and the two flexible cables are arranged in a crosswise manner.

[0006] Preferably, the first damper is a viscoelastic damper. The top end of the viscoelastic damper is connected to the end of the flexible cable, and the bottom end is fixedly connected to the top end of the horizontal support plate.

[0007] Preferably, the second damper is a torsional damper. The torsional damper includes two steel plates arranged along the direction of the beam body. The two steel plates are arranged oppositely, and a plurality of low-yield-point metal round tubes arranged horizontally perpendicular to the direction of the beam body are connected between the two steel plates. A connecting plate is connected between the plurality of low-yield-point metal round tubes. One end of the connecting plate is connected to the end of the flexible cable, and the bottom end of the steel plate is fixedly connected to the top end of the horizontal support plate.

[0008] A method for calculating the amplification factor of a damper shock absorption amplification device for a bridge includes the following steps:

[0009] (1) Determine the expressions of Δx and Δy as shown in Equations (1) and (2).

[0010]

[0011] In Equations (1) and (2), Δx refers to the horizontal deformation of point B; Δy refers to the vertical deformation of point B, and point B represents the end point of the plate body of the seesaw device; δ BC represents the axial deformation of the cable, δ represents the horizontal deformation of the beam body. The length of the cable before deformation is AB and BC, and the length of the cable after deformation is The angle between the plate body of the seesaw device and the horizontal plane is β. When not deformed, the angle between one of the flexible cables and the horizontal plane is α. After deformation, the angle between the plate body of the seesaw device and the horizontal plane is θ1, and the angle between the flexible cable 7 after deformation and before deformation is θ2. Force represents the horizontal seismic action received by the beam body, and h represents the height of the end of the plate body of the seesaw device;

[0012] When θ1 and θ2 are relatively small, then Equations (1) and (2) are simplified as follows:

[0013]

[0014] According to the definition of the amplified displacement of the damper, the expression of the amplified displacement of the damper is obtained as follows:

[0015]

[0016] Substitute Equations (3) and (4) into Equation (5) to determine the displacement amplification value of one side of the damper;

[0017] According to Equation (5), determine the displacement amplification multiple of the damper as shown in Equation (6):

[0018]

[0019] Since the angle β is relatively small in practical engineering, it is determined that Δx is relatively small compared to Δy. When the influence of Δx is ignored, Equation (6) is simplified to Equation (7) as follows:

[0020]

[0021] Substituting Equation (4) into Equation (7) and simplifying, the final magnification factor is obtained as shown in Equation (8):

[0022]

[0023] Equation (8) is only the magnification factor on one side. Considering both sides, the magnification factor of the entire shock absorption system is as shown in Equation (9):

[0024]

[0025] The beneficial effects of a damper shock absorption magnification device for bridges according to the present invention are as follows:

[0026] In bridge structures, although energy dissipation and shock absorption devices such as seismic isolation bearings can play a certain role in energy dissipation and shock absorption, with the continuous development of bridge structures, due to improper structural measures or other measures restricting the horizontal deformation of the beam body between multi-span bridges, the actual shock absorption effect of devices such as seismic isolation bearings is not ideal at this time. In order to enable the damper to play a greater role in energy dissipation and shock absorption under smaller deformations in bridge engineering, the present invention proposes a flexible cable seesaw magnification device to connect different types of dampers to achieve the purpose of efficient shock absorption. Since a single type of damper or a single type of damper is mostly used to construct the magnification device in actual engineering, the present invention, in order to overcome the drawbacks of the above practices, specifically proposes a magnification device capable of magnifying the deformations of various types of dampers. The greatest advantage of this type of magnification device is that it has a large magnification effect and converts the horizontal deformation of the beam body relative to the pier into the vertical deformation and torsional deformation of different types of dampers. Understanding the function of this type of magnification device from the perspective of energy conversion, it can be considered that this type of magnification device realizes various forms of energy conversion, which is an advantage not possessed by previous magnification devices. In addition, compared with existing magnification devices, the present invention has the characteristics of a small cross-section of components, less space occupation, and a large magnification factor. Through the calculation formula given by the present invention, the magnification factor of the magnification device during actual earthquakes can be simulated and calculated, thereby providing a guarantee for the reasonable use of the device. Description of the Drawings

[0027] Figure 1 It is a structural diagram of a damper shock absorption magnification device for bridges.

[0028] Figure 2 is Figure 1 A top view structural schematic diagram in the A - A direction.

[0029] Figure 3 Schematic diagram of the deformation of the shock absorption amplification device.

[0030] Figure 4 Analysis diagram of the amplification coefficient.

[0031] 1. Beam body; 2. Pier column; 3. Oblique support rod; 4. Seesaw device; 5. First damper; 6. Second damper; 61. Steel plate; 62. Low yield point metal round tube; 63. Connecting plate; 7. Flexible cable; 8. Horizontal support plate. Specific implementation mode

[0032] The following description is only for the preferred embodiments of the present invention and is not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

[0033] The following embodiments can be understood as separately expressing a part of the local structure or method of the present invention, or can also be understood as the embodiments combined with each other to explain the connotation of the structure or method in a larger scope of the present invention.

[0034] Embodiment 1

[0035] A damper shock absorption amplification device for a bridge, as Figure 1 shown, the amplification device is arranged between the pier column 2 and the beam body 1, and includes a horizontal support plate 8 with one end fixedly connected to the pier column 2 and the other end extending along the beam body. The bottom of the horizontal support plate 8 is connected to the pier column 2 through an oblique support rod 3 (to improve the strength of the horizontal support plate 8 and ensure stability during earthquake resistance). A seesaw device 4 is arranged at the upper end of the horizontal support plate 8. The two ends of the plate body of the seesaw device 4 are respectively connected to the horizontal support plate 8 through a first damper 5 and a second damper 6. The two ends of the plate body of the seesaw device 4 are respectively connected to the bottom of the beam body through flexible cables 7, and the two flexible cables 7 are arranged in a cross manner.

[0036] As Figure 1 shown, the first damper 5 is a viscoelastic damper. The top end of the viscoelastic damper is connected to the end of the flexible cable 7, and the bottom end is fixedly connected to the top end of the horizontal support plate 8.

[0037] As Figure 1 , 2As shown in the figure, the second damper 6 is a torsion damper. The torsion damper includes two steel plates 61 arranged along the direction of the beam body 1. The two steel plates 61 are arranged oppositely. A plurality of low-yield-point metal round tubes 62 are connected between the two steel plates 61 and arranged horizontally perpendicular to the direction of the beam body 1. A connecting plate 63 is connected between the plurality of low-yield-point metal round tubes 62. One end of the connecting plate 63 is connected to the end of the flexible cable 7. The bottom end of the steel plate 61 is fixedly connected to the top end of the horizontal support plate 8.

[0038] This embodiment gives the detailed structure of the amplification device. Among them, the working principle of the amplification device is as follows: when the beam body 1 generates a horizontal relative movement relative to the pier 2 under the action of a horizontal earthquake, one of the flexible cables 7 will be tensioned, and the plate body of the seesaw device 4 will be driven to rotate, driving the first damper 5 and the second damper 6 connected to both ends of the plate body to deform, forcing the first damper 5 and the second damper 6 to enter the working state. The horizontal deformation of the beam body 1 relative to the pier 2 is converted into the vertical deformation of the first damper 5 and the torsional deformation of the second damper 6 by driving the plate body of the seesaw device 4 to rotate through the cable 7, so as to play the role of energy dissipation and shock absorption.

[0039] Embodiment 2

[0040] A method for calculating the amplification coefficient of a damper shock absorption amplification device for a bridge is as follows Figure 3 As shown in the figure, it includes the following steps:

[0041] (1) Determine the expressions of Δx and Δy as shown in Equation (1) and Equation (2).

[0042]

[0043] In Equation (1) and Equation (2), Δx refers to the horizontal deformation of point B; Δy refers to the vertical deformation of point B. Point B represents the end point of the plate body of the seesaw device 4; δ BC represents the axial deformation of the cable. δ represents the horizontal deformation of the beam body. The length of the cable before deformation is AB and BC, and the length of the cable after deformation is The angle between the plate body of the seesaw device 4 and the horizontal plane is β. When it is not deformed, the angle between one of the flexible cables 7 and the horizontal plane is α. After deformation, the angle between the plate body of the seesaw device 4 and the horizontal plane is θ1, and the angle between the flexible cable 7 after deformation and before deformation is θ2. Force represents the horizontal earthquake action received by the beam body, and h represents the height of the end of the plate body of the seesaw device;

[0044] When θ1 and θ2 are relatively small (sinθ1≈θ1, sinθ2≈θ2), then Equation (1) and Equation (2) are simplified as follows:

[0045]

[0046] According to the definition of the amplified displacement of the damper, the expression for the amplified displacement of the damper is as follows:

[0047]

[0048] Substitute Equation (3) and Equation (4) into Equation (5) to determine the displacement amplification value of one side of the damper;

[0049] According to Equation (5), the displacement amplification factor of the damper is as shown in Equation (6):

[0050]

[0051] Since the angle of β is relatively small in actual engineering, it is determined that Δx is relatively small compared to Δy. When the influence of Δx is ignored, Equation (6) is simplified to Equation (7) as follows:

[0052]

[0053] Substitute Equation (4) into Equation (7), and after simplification, the final amplification coefficient is obtained, as shown in Equation (8):

[0054]

[0055] Equation (8) is only the amplification coefficient of one side. Considering both sides, the amplification coefficient of the entire shock absorption system is as shown in Equation (9):

[0056]

[0057] In this embodiment, in order to analyze the shock absorption and amplification effect of this amplification device, α, β and are used as analysis parameters. Through Figure 3 it can be seen that as increases, the maximum amplification coefficient shows a gradually decreasing trend. As α increases, the amplification coefficient f gradually decreases; as β increases, the amplification coefficient f gradually increases. Through the above analysis, it can be known that when manufacturing this kind of amplification device, attention should be paid to the deformation of the stay cable itself and it should not have a large axial elongation ability, otherwise, it will have a greater impact on the amplification coefficient f. As Figure 4 shown, it is the amplification coefficient analysis diagram, which is a numerical simulation calculation and analysis based on Equation (1) and Equation (2), indicating the actual amplification effect of this kind of amplification device.

Claims

1. A damping shock amplification device for a bridge, characterized in that The described amplification device is arranged between the pier column and the beam body, and includes a horizontal support plate with one end fixedly connected to the pier column and the other end extending along the direction of the beam body. The bottom of the horizontal support plate is connected to the pier column through an inclined support rod. A seesaw device is arranged at the upper end of the horizontal support plate. Both ends of the plate body of the seesaw device are connected to the horizontal support plate through a first damper and a second damper respectively. Both ends of the plate body of the seesaw device are connected to the bottom of the beam body through flexible cables, and the 2 flexible cables are arranged in a crosswise manner.

2. The shock absorber amplification device for a bridge according to claim 1, characterized in that The first damper is a viscoelastic damper. The top end of the viscoelastic damper is connected to the end of the flexible cable, and the bottom end is fixedly connected to the top end of the horizontal support plate.

3. The shock absorber damping amplification device for a bridge according to claim 2, characterized in that, The second damper is a torsional damper. The torsional damper includes 2 steel plates arranged along the direction of the beam body. The 2 steel plates are arranged oppositely, and multiple low-yield-point metal round tubes are connected between the 2 steel plates and arranged horizontally perpendicular to the direction of the beam body. A connecting plate is connected between the multiple low-yield-point metal round tubes. One end of the connecting plate is connected to the end of the flexible cable, and the bottom end of the steel plate is fixedly connected to the top end of the horizontal support plate.

4. The calculation method of the amplification factor of a damper shock absorption amplification device for a bridge according to claim 3, characterized in that, It includes the following steps: (1) Determine the expressions of Δx and Δy as shown in Formula (1) and Formula (2). In Formula (1) and Formula (2), Δx refers to the horizontal deformation of point B; Δy refers to the vertical deformation of point B, and point B represents the end point of the plate body of the seesaw device. δ BC represents the axial deformation of the cable, δ represents the horizontal deformation of the beam body. The lengths of the cables are AB and BC before deformation, and the lengths of the cables after deformation are The angle between the plate body of the seesaw device and the horizontal plane is β. Before deformation, the angle between one of the flexible cables and the horizontal plane is α. After deformation, the angle between the plate body of the seesaw device and the horizontal plane is θ1, and the angle between the flexible cable 7 before and after deformation is θ2. Force represents the horizontal seismic action on the beam body, and h represents the height of the end of the plate body of the seesaw device; When θ1 and θ2 are relatively small, then Formula (1) and Formula (2) are simplified as follows: According to the definition of the amplified displacement of the damper, the expression of the amplified displacement of the damper is obtained as follows: Substitute Formula (3) and Formula (4) into Formula (5) to determine the displacement amplification value of one side of the damper. According to Formula (5), determine the displacement amplification multiple of the damper as shown in Formula (6): Since the angle of β is relatively small in actual engineering, it is determined that Δx is relatively small compared to Δy. When the influence of Δx is ignored, Formula (6) is simplified to Formula (7) as shown: Substitute Formula (4) into Formula (7), and after simplification, the final amplification coefficient is obtained, as shown in Formula (8): Formula (8) is only the amplification coefficient of one side. Considering both sides, the amplification coefficient of the entire shock absorption system is as shown in Formula (9):

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