Bridge seismic mitigation and isolation support

Abstract

The utility model relates to the technical field of bridge supports, in particular to a bridge shock absorption and isolation support which comprises a support top plate, a support bottom plate, a hollow spherical plate and a steel cylinder, the hollow spherical plate is installed on the top of the steel cylinder, the support top plate is arranged on the hollow spherical plate in a sliding mode, and the steel cylinder is arranged on the support bottom plate. The support top plate and the hollow spherical plate can form a first limit, and the steel cylinder is installed on the support bottom plate through a shear pin. The shear pin can restrain the steel cylinder in a normal use state and under an E1 earthquake working condition, and meanwhile, the displacement of the rubber support is also limited, so that the movement of the support top plate is limited, the normal use performance of a bridge is ensured, and the normal use performance of the bridge is ensured. When an E2 earthquake occurs, large horizontal force enables the shear pin to be sheared off, constraint on the steel cylinder is released, at the moment, the support top plate drives the steel cylinder to move together, and therefore the displacement amount of the support top plate is increased, and the displacement response requirement of a bridge is met under the large earthquake.

Description

Technical Field

[0001] The utility model relates to the technical field of bridge supports, in particular to a bridge seismic isolation support. Background Art

[0002] Bridge bearings are important components of bridges. They can transmit vertical and horizontal forces, release various deformations, and also have the effects of shock absorption and seismic isolation.

[0003] Currently, bridge isolation bearings on the market are primarily categorized as shear deformation bearings and sliding bearings. Shear deformation bearings are typically made by vulcanizing a steel plate with a polymer material such as rubber. Their ability to withstand vertical loads is limited, limiting their scope of application. Furthermore, they may experience accelerated aging due to excessive stress on the bearings caused by partial debonding. Sliding bearings, which primarily use steel to bear vertical loads, have a much wider range of applicability than shear deformation bearings. However, they suffer from large beam end displacements, a heavy reliance on fixed piers, and poor self-resetting capabilities.

[0004] For example, the Chinese invention patent with application number CN202310999577.7 discloses a bridge bearing and a bridge, and proposes a bridge bearing that combines the advantages of shear deformation bearings and sliding bearings. A steel cylinder and a polytetrafluoroethylene slide are used to bear vertical loads. A colloid bearing connected to the main beam is placed in the steel cylinder. When an earthquake occurs, the horizontal force can be evenly dispersed on each bridge pier, and the friction between the polytetrafluoroethylene slide and the bearing top plate can release part of the seismic energy. In addition, the bearing can also prevent the beam from falling by restricting the colloid slider through the steel cylinder.

[0005] Currently, bridge seismic design is primarily categorized into two types: E1 and E2. E1, the first level of fortification, typically corresponds to earthquakes with a short recurrence period at the project site. This level of fortification requires the structure to remain elastic and undamaged under earthquakes. E2, the second level of fortification, typically corresponds to earthquakes with a longer recurrence period at the project site. This level of fortification allows the structure to enter an elastic-plastic state under earthquakes, but prevents severe damage or collapse. The displacement response of the bridge in this state is significantly greater than in E1.

[0006] However, a bridge bearing and a bridge with application number CN202310999577.7 disclose a bridge bearing scheme that only considers the functional requirements of the E2 state. The bottom of the steel cylinder is rigidly connected to the bearing base plate. When the colloid bearing slides in the steel cylinder, in order to meet the horizontal displacement requirements of the main beam under the E2 earthquake state, the steel cylinder diameter is larger and the production cost is higher. Utility Model Content

[0007] The purpose of the utility model is to provide a bridge seismic isolation bearing in view of the fact that the current bridge bearing only considers the functional requirements of the E2 state, the bottom of the steel cylinder is rigidly connected to the bearing base plate, and when the colloid bearing slides in the steel cylinder, in order to meet the horizontal displacement requirements of the main beam under the E2 earthquake state, the steel cylinder diameter is large and the production cost is high.

[0008] The utility model provides a bridge seismic isolation bearing, including a bearing top plate, a bearing bottom plate, a hollow spherical plate and a steel cylinder. The hollow spherical plate is installed on the top of the steel cylinder, the bearing top plate is slidably set on the hollow spherical plate, and the bearing top plate can form a first limit between the hollow spherical plate, and the steel cylinder is installed on the bearing bottom plate through a shear pin.

[0009] The shear-type bridge bearing of the present invention has a hollow spherical plate installed on the top of the steel cylinder, and the bearing top plate is slidably set on the hollow spherical plate, and the bearing top plate can form a first limit with the hollow spherical plate, and the steel cylinder is installed on the bearing bottom plate through a shear pin. In normal use and E1 earthquake conditions, the shear pin on the bearing bottom plate constrains the steel cylinder so that the steel cylinder is fixed to the bearing bottom plate. Since the bearing top plate can form a first limit with the hollow spherical plate, when the main beam is displaced, the bearing top plate and the hollow spherical plate form a limit, and the bearing top plate transmits the force to the hollow spherical plate, and the hollow spherical plate transmits the force to the steel cylinder. Since the steel cylinder is in a fixed state, the movement of the bearing top plate is restricted, and then the displacement of the main beam is restricted. displacement, ensuring the normal performance of the bridge; under the E2 earthquake condition, the main beam transmits a large horizontal force to the bearing top plate, the bearing top plate transmits the force to the hollow spherical plate, and the hollow spherical plate transmits the force to the steel cylinder. After the large horizontal force shears the shear pin, the constraint of the bearing bottom plate on the steel cylinder is released. At this time, the bearing top plate drives the steel cylinder to displace together, thereby increasing the displacement of the bearing top plate, so that under the E2 earthquake condition, the displacement response requirements of the bridge are met, thereby avoiding the risk of the main beam falling under the E2 earthquake condition, and realizing that the steel cylinder designed according to the E1 earthquake condition can meet the use under the E2 earthquake condition. Compared with the existing solution, this solution greatly reduces the diameter of the bearing steel cylinder and saves steel.

[0010] Preferably, a mounting groove is provided at the bottom of the steel cylinder, a mounting hole is opened on the support base plate, one end of the shear pin is installed in the mounting groove, and the other end of the shear pin is placed in the mounting hole.

[0011] Preferably, the mounting grooves are arranged in a circular array at the bottom of the steel cylinder;

[0012] The mounting holes are arranged at annular intervals on the support base plate.

[0013] Preferably, the bearing capacity of the shear pin is smaller than the bearing capacity of the steel cylinder.

[0014] Preferably, it also includes a colloid support arranged inside the steel cylinder, the top of the colloid support has an upper connecting plate connected to the support top plate, the bottom of the colloid support has a lower connecting plate connected to the support bottom plate, and the upper connecting plate can abut against the hollow spherical plate to form the first limit.

[0015] Preferably, the steel cylinder can abut against the support base plate to form a second limit.

[0016] Preferably, it further comprises a planar annular slide plate, which is mounted on the top of the hollow spherical plate, and the support top plate abuts against the planar annular slide plate.

[0017] Preferably, it further comprises a spherical annular slide plate, which is mounted on the top of the steel cylinder, and the hollow spherical plate abuts against the spherical annular slide plate.

[0018] Preferably, a pin is provided on the upper connecting plate, and the pin is inserted into the support top plate.

[0019] Preferably, the lower connecting plate is connected to the support base plate by fixing bolts.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] The shear-type bridge bearing of the present invention has a hollow spherical plate installed on the top of the steel cylinder, and the bearing top plate is slidably set on the hollow spherical plate, and the bearing top plate can form a first limit with the hollow spherical plate, and the steel cylinder is installed on the bearing bottom plate through a shear pin. In normal use and E1 earthquake conditions, the shear pin on the bearing bottom plate constrains the steel cylinder so that the steel cylinder is fixed to the bearing bottom plate. Since the bearing top plate can form a first limit with the hollow spherical plate, when the main beam is displaced, the bearing top plate and the hollow spherical plate form a limit, and the bearing top plate transmits the force to the hollow spherical plate, and the hollow spherical plate transmits the force to the steel cylinder. Since the steel cylinder is in a fixed state, the movement of the bearing top plate is restricted, and then the displacement of the main beam is restricted. displacement, ensuring the normal performance of the bridge; under the E2 earthquake condition, the main beam transmits a large horizontal force to the bearing top plate, the bearing top plate transmits the force to the hollow spherical plate, and the hollow spherical plate transmits the force to the steel cylinder. After the large horizontal force shears the shear pin, the constraint of the bearing bottom plate on the steel cylinder is released. At this time, the bearing top plate drives the steel cylinder to displace together, thereby increasing the displacement of the bearing top plate, so that under the E2 earthquake condition, the displacement response requirements of the bridge are met, thereby avoiding the risk of the main beam falling under the E2 earthquake condition, and realizing that the steel cylinder designed according to the E1 earthquake condition can meet the use under the E2 earthquake condition. Compared with the existing solution, this solution greatly reduces the diameter of the bearing steel cylinder and saves steel. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the structure of this application Figure 1 .

[0023] Figure 2 This is a cross-sectional view of the present application.

[0024] Figure 3 This is a schematic diagram of the mounting holes provided on the base plate of the support of the present application.

[0025] Figure 4 It is a schematic diagram of the installation groove provided at the bottom of the steel cylinder of the present application.

[0026] Figure 5 This is a schematic diagram of the support operation during normal use and E1 earthquake conditions. Figure 1 .

[0027] Figure 6 This is a schematic diagram of the support operation during normal use and E1 earthquake conditions. Figure 2 .

[0028] Figure 7 This is the support working diagram under E2 earthquake condition Figure 1 .

[0029] Figure 8 This is the support working diagram under E2 earthquake condition Figure 2 .

[0030] Figure 9 It is the force diagram of the shear pin.

[0031] Markings in the figure:

[0032] 1-support top plate, 2-support bottom plate, 21-mounting hole, 3-hollow spherical plate, 4-steel cylinder, 41-mounting groove, 5-colloid support, 6-shear pin, 7-flat annular slide, 8-spherical annular slide, 9-pin shaft, 10-fixing bolt, 20-upper connecting plate, 30-lower connecting plate, 40-embedded screw. DETAILED DESCRIPTION

[0033] The present invention will be further described in detail below with reference to specific embodiments. However, this should not be construed as limiting the scope of the present invention to the following embodiments. All technologies implemented based on the present invention fall within the scope of the present invention.

[0034] Unless otherwise specified, in the description of the specific embodiments of the present invention, the terms indicating orientation or positional relationships, such as "upper," "lower," "left," "right," "center," "inside," and "outside," are based on the orientation or positional relationships shown in the accompanying drawings, or are the orientation or positional relationships in which the product / device / apparatus of the present invention is typically placed when in use. These terms indicating orientation or positional relationships are merely for the purpose of facilitating the description of the present invention or simplifying the description of the specific embodiments to facilitate a quick understanding of the solutions by technicians. They do not indicate or imply that a particular device / component / element must have a specific orientation or be constructed and operated in a specific positional relationship, and therefore should not be construed as limiting the present invention.

[0035] In addition, if the terms "horizontal", "vertical", "overhanging", "parallel" and the like appear, it does not mean that the corresponding devices / components / elements are required to be absolutely horizontal or vertical or overhanging or parallel, but may be slightly tilted or have deviations. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but may be slightly tilted. Alternatively, it can be simply understood that the corresponding devices / components / elements are set in directions such as "horizontal", "vertical", "overhanging", and "parallel", and can have an error / deviation of ±10% relative to the corresponding direction setting, more preferably an error / deviation within ±8%, more preferably an error / deviation within ±6%, more preferably an error / deviation within ±5%, and more preferably an error / deviation within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its role in the solution of the present utility model.

[0036] In addition, the expressions "first", "second", "third", etc. that appear in the terms are merely descriptions used to distinguish the same or similar components and should not be understood as emphasizing or implying the relative importance of specific components.

[0037] In addition, in the description of the embodiments of the present invention, "several", "a plurality", and "a number" represent at least 2. It can be any number such as 2, 3, 4, 5, 6, 7, 8, 9, and even more than 9.

[0038] Furthermore, in the description of the technical solutions of this utility model, unless otherwise expressly specified / defined / restricted, the terms "disposed," "installed," "connected," "connected," "provided with," "laid," and "arranged" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections. They may be welding, riveting, bolting, threading, or other commonly used connection methods in the art. Such connections may be mechanical, electrical, or communication connections; they may be direct connections, indirect connections through an intermediate medium, or internal connections between two components.

[0039] Example 1

[0040] like Figure 1-Figure 4 As shown, a bridge seismic isolation bearing includes a bearing top plate 1, a bearing bottom plate 2, a hollow spherical plate 3 and a steel cylinder 4. The hollow spherical plate 3 is installed on the top of the steel cylinder 4. The bearing top plate 1 is slidably set on the hollow spherical plate 3, and the bearing top plate 1 can form a first limit between the hollow spherical plate 3. The steel cylinder 4 is installed on the bearing bottom plate 2 through the shear pin 6.

[0041] like Figure 2 As shown, the hollow spherical plate 3 is installed on the top of the steel cylinder 4, the support top plate 1 is slidably set on the hollow spherical plate 3, and the support top plate 1 can form a first limit between the hollow spherical plate 3, and the steel cylinder 4 is installed on the support bottom plate 2 through the shear pin 6. In normal use and E1 earthquake conditions, Figure 5-Figure 6 As shown, the shear pins 6 on the bearing bottom plate 2 constrain the steel cylinder 4, so that the steel cylinder 4 is fixed on the bearing bottom plate 2. Since the bearing top plate 1 can form a first limit with the hollow spherical plate 3, when the main beam is displaced, the bearing top plate 1 and the hollow spherical plate 3 form a limit, and the bearing top plate 1 transmits the force to the hollow spherical plate 3, and the hollow spherical plate 3 transmits the force to the steel cylinder 4. Since the steel cylinder 4 is in a fixed state, the movement of the bearing top plate 1 is restricted, and the displacement of the main beam is restricted, thereby ensuring the normal performance of the bridge. Under the E2 earthquake condition, as shown in FIG. Figure 7-Figure 8 As shown, the main beam transmits a large horizontal force to the bearing top plate 1, and the bearing top plate 1 transmits the force to the hollow spherical plate 3, and the hollow spherical plate 3 transmits the force to the steel cylinder 4. After the large horizontal force shears the shear pin 6, the constraint of the bearing bottom plate 2 on the steel cylinder 4 is released. At this time, the bearing top plate 1 drives the steel cylinder 4 to displace together, thereby increasing the displacement of the bearing top plate 1, so that under the E2 earthquake condition, the displacement response requirements of the bridge are met, thereby avoiding the risk of the main beam falling under the E2 earthquake condition, and realizing that the steel cylinder designed according to the E1 earthquake condition can meet the use under the E2 earthquake condition. Compared with the existing solution, this solution greatly reduces the diameter of the bearing steel cylinder and saves steel.

[0042] In one or more embodiments, Figure 4 As shown, a mounting groove 41 is provided at the bottom of the steel cylinder 4. Figure 3 As shown, a mounting hole 21 is opened on the support base plate 2 , one end of the shear pin 6 is installed in the mounting groove 41 , and the other end of the shear pin 6 is placed in the mounting hole 21 .

[0043] By setting a mounting groove 41 at the bottom of the steel cylinder 4 and opening a mounting hole 21 at the corresponding position of the support base plate 2, the shear pin 6 is installed. One end of the shear pin 6 is installed in the mounting groove 41, and the other end of the shear pin 6 is placed in the mounting hole 21, so that the steel cylinder 4 is installed on the support base plate 2 through the shear pin 6.

[0044] Furthermore, the shear pin 6 is machined and made of 42CrMo steel, which is subjected to quenching and tempering treatment. The shear pin 6 is tightly matched with the mounting hole 21 and the mounting groove 41 .

[0045] In an optional embodiment, if Figure 4 As shown, the mounting grooves 41 are arranged in a circular array on the bottom of the steel cylinder 4, that is, a plurality of equally spaced mounting grooves 41 are provided in a circular pattern on the bottom of the steel cylinder 4;

[0046] like Figure 3 As shown, the mounting holes 21 are arranged at annular intervals on the support base plate 2.

[0047] By arranging mounting grooves 41 circumferentially at the bottom of the steel cylinder 4 and arranging mounting holes 21 at corresponding annular intervals on the support base plate 2, it is ensured that the annular area where the steel cylinder 4 contacts the support base plate 2 can be effectively fixed on the support base plate 2.

[0048] In an optional embodiment, the number of shear pins 6 is not less than four.

[0049] In one or more embodiments, the bearing capacity of the shear pin 6 is smaller than the bearing capacity of the steel cylinder 4 .

[0050] After the shear-type bridge bearing is subjected to force, since the bearing capacity of the shear pin 6 is less than the bearing capacity of the steel cylinder 4, it can ensure that the shear pin 6 is sheared before the steel cylinder 4 is damaged, thereby releasing the constraint of the bearing bottom plate 2 on the steel cylinder 4, and then allowing the steel cylinder 4 to move on the bearing bottom plate 2, thereby increasing the sliding displacement of the bearing top plate 1, releasing the displacement of the bridge under the E2 earthquake, and ensuring that the displacement response requirements of the bridge are met under the E2 earthquake condition.

[0051] In this embodiment, the bearing capacity of the shear pin 6 refers to the shear fracture bearing capacity of the shear pin 6, and the bearing capacity of the steel cylinder 4 refers to the tensile fracture bearing capacity of the steel cylinder 4, ensuring that the shear pin 6 is sheared before the tensile fracture of the steel cylinder 4 occurs, thereby releasing the constraint of the support base plate 2 on the steel cylinder 4, and allowing the steel cylinder 4 to move on the support base plate 2.

[0052] In one or more embodiments, Figure 1 、 Figure 2 As shown, it also includes a colloid support 5 arranged inside the steel cylinder 4, the top of the colloid support 5 has an upper connecting plate 20 connected to the support top plate 1, and the bottom of the colloid support 5 has a lower connecting plate 30 connected to the support bottom plate 2, and the upper connecting plate 20 can abut against the hollow spherical plate 3 to form a first limit, as shown. Figure 6 .

[0053] like Figure 5-Figure 6As shown, during normal use and E1 earthquake conditions, when the main beam moves, the main beam drives the support top plate 1 to displace, and at this time the support top plate 1 drives the upper connecting plate 20 to displace together. After the support top plate 1 moves to the upper connecting plate 20 and abuts against the hollow spherical plate 3, a first limit is formed between the support top plate 1 and the hollow spherical plate 3. The support top plate 1 transfers the force to the hollow spherical plate 3, and the hollow spherical plate 3 transfers it to the steel cylinder 4. The steel cylinder 4 is fixed to the support bottom plate 2 through the shear pin 6 to limit the movement of the support top plate 1, and then to limit the displacement of the main beam, thereby ensuring the normal performance of the bridge.

[0054] In an optional embodiment, if Figure 8 As shown, the steel cylinder 4 can abut against the lower connecting plate 30 to form a second limit.

[0055] like Figure 7-Figure 8 As shown, under the E2 earthquake condition, after the bearing top plate 1 moves to the upper connecting plate 20 and abuts against the hollow spherical plate 3, due to the large horizontal force transmitted to the bearing top plate 1 by the main beam, the bearing top plate 1 transmits the force to the hollow spherical plate 3, and the hollow spherical plate 3 transmits the force to the steel cylinder 4. After the large horizontal force shears the shear pin 6, the constraint of the bearing bottom plate 2 on the steel cylinder 4 is released. At this time, the bearing top plate 1 drives the steel cylinder 4 to displace together, thereby increasing the sliding displacement of the bearing top plate 1, so that the displacement response requirements of the bridge are met under the E2 earthquake condition;

[0056] When the steel cylinder 4 moves on the support base plate 2 until it abuts against the lower connecting plate 30, a second limit is formed between the steel cylinder 4 and the lower connecting plate 30, thereby limiting the further displacement of the steel cylinder 4 and preventing the steel cylinder 4 from sliding out of the support base plate 2 driven by the support top plate 1, thereby limiting the further displacement of the steel cylinder and preventing the main beam from having excessive displacement and the risk of falling beams.

[0057] In one or more embodiments, Figure 2 As shown, it also includes a planar annular slide plate 7, which is installed on the top of the hollow spherical plate 3, and the support top plate 1 is in contact with the planar annular slide plate 7.

[0058] By providing a planar annular slide plate 7, it is ensured that the support top plate 1 can slide on the hollow spherical plate 3 so that the support top plate 1 moves along with the main beam.

[0059] It also includes a spherical annular slide plate 8, which is installed on the top of the steel cylinder 4, and the hollow spherical plate 3 abuts against the spherical annular slide plate 8.

[0060] By providing a spherical annular slide plate 8, it is ensured that the hollow spherical plate 3 can swing relatively on the steel cylinder 4 to release the displacement caused by the rotation of the main beam.

[0061] In an optional embodiment, an observation hole is further provided on the outer wall of the steel cylinder 4 .

[0062] In an optional embodiment, embedded screws 40 are further connected to the support top plate 1 and the support bottom plate 2.

[0063] The working principle of the shear type bridge bearing in this embodiment is:

[0064] like Figure 5-Figure 8 As shown, shear pins 6 constrain steel cylinder 4 in both normal use and under E1 earthquake conditions, while also limiting the displacement of colloid bearings 5. This prevents the main beam from excessively displacing in both conditions, ensuring the bridge's normal performance. During an E2 earthquake, the larger horizontal force causes shear pins 6 to shear, releasing the constraint on steel cylinder 4 and increasing the sliding displacement of colloid bearings 5, thus meeting the bridge's displacement response requirements under larger earthquakes.

[0065] This implementation also discloses the entire workflow of the shear-type bridge bearing, specifically:

[0066] (1) Under normal use: the displacement of the main beam end due to temperature changes, traffic loads, etc. will be transmitted to the support top plate 1, and the horizontal force on the support top plate 1 will be transmitted to the upper connecting plate 20 of the colloid support 5, causing the upper connecting plate 20 to move horizontally. The lower connecting plate 30 of the colloid support 5 is connected to the support bottom plate 2 and fixed to the lower structure of the bridge. Therefore, the colloid support 5 will undergo shear deformation. When the displacement of the support top plate 1 is large and reaches the inner edge of the hollow spherical plate 3, the friction between the shear pin 6, the steel cylinder 4 and the support bottom plate 2 will act together, and the displacement of the upper connecting plate 20 of the colloid support 5 will be limited, avoiding large displacement of the main beam and affecting the normal use of the bridge.

[0067] (2) Earthquake conditions: In normal use and under E1 earthquake conditions, the shear pins 6 are not sheared off, and the upper connecting plate 20 of the colloidal support 5 connecting the main beam is restricted by the steel cylinder 4. When an E2 earthquake occurs, the horizontal relative displacement between the main beam and the bridge substructure is large. Under the action of a large horizontal force, the upper connecting plate 20 of the colloidal support 5 will shear off the shear pins 6 between the steel cylinder 4 and the support bottom plate 2, thereby releasing the restraining effect of the steel cylinder 2 on the support top plate 1, thereby adapting to the large displacement of the main beam under the earthquake state. When the displacement of the main beam reaches a certain extent, the steel cylinder 4 will contact the lower connecting plate 30 of the colloidal support 5. Because the lower connecting plate 30 is fixed to the support bottom plate 2, the lower connecting plate 30 will restrict the further displacement of the steel cylinder 4, thereby achieving a limiting effect and preventing the main beam from causing excessive displacement and the risk of falling beams.

[0068] This embodiment also discloses a design method for the shear pin 6:

[0069] Taking the LNZ-1250-±55 / ±110 bearing under a 7-degree earthquake intensity as an example (the vertical bearing capacity of the bearing is 1250kN, the maximum displacement under normal working conditions (including E1 earthquake conditions) is ±55mm, and the maximum displacement under E2 earthquake conditions is ±110mm), the design calculation of the shear pin is demonstrated:

[0070] The shear pin 6 is made of 42CrMo steel, which is quenched and tempered.

[0071] σ S =930Mpa

[0072] σ b =1080Mpa

[0073] τ s =0.6×σ s =558MPa

[0074] τ b =0.6×σ b =648MPa

[0075] like Figure 9 As shown, the diameter of the shear pin 6 should meet

[0076]

[0077] in,

[0078] Q min ——Lower limit of shear force (kN), for 1250 type support,

[0079] Design Q min =1250×0.1×0.9=112.5kN

[0080] Among them, 0.1 is the maximum horizontal acceleration in the 7-degree earthquake zone, and 0.9 is the lower limit coefficient of the horizontal force.

[0081] Q max ——Upper limit of shear force (kN)

[0082] Design Q max =1250×0.1×1.1=137.5kN

[0083] Among them, 0.1 is the maximum horizontal acceleration in the 7-degree earthquake zone, and 1.1 is the upper coefficient of the horizontal force.

[0084] z——Number of shear pins

[0085] After calculation, for the 1250 type bearing, the number of shear pins 6 is set to 4, and the diameter (minor diameter) is designed to be 8.01mm≤d0≤8.21mm.

[0086] Example 2

[0087] On the basis of Example 1, Figure 2 As shown, a bridge seismic isolation bearing of this embodiment has a pin shaft 9 provided on the upper connecting plate 20 , and the pin shaft 9 is inserted into the bearing top plate 1 .

[0088] Since the upper connecting plate 20 is connected to the support top plate 1 by a pin connection, the support top plate 1 and the colloid support 5 can be disassembled, thereby facilitating the removal of the support top plate 1 and the subsequent inspection and maintenance of the colloid support 5.

[0089] In an optional embodiment, if Figure 2 As shown, the lower connecting plate 30 is connected to the support base plate 2 by fixing bolts 10.

[0090] The lower connecting plate 30 of the colloid support 5 is connected to the support base plate 2 by the fixing bolts 10, so that the colloid support 5 is fixed on the support base plate 2, forming a firm limiting measure to prevent the colloid support 5 from being displaced on the support base plate 2. In this embodiment, the bearing capacity of the fixing bolts 10 is greater than the force exerted by the main beam on the shear-type bridge support in the E2 state to ensure that the fixing bolts 10 will not be sheared in the E2 state.

[0091] In one or more embodiments, a chrome-plated layer is provided on the surface of the support base plate 2. The chrome-plated layer on the support base plate 2 forms a corrosion-resistant chrome-plated layer, effectively protecting the support base plate 2 from corrosion. It also increases the hardness of the support base plate 2 and the friction between the steel cylinder 4 and the support base plate 2. When the steel cylinder 4 is subjected to the horizontal force generated by the displacement of the main beam, the friction between the steel cylinder 4 and the support base plate 2 can offset part of the horizontal force generated by the displacement of the main beam on the steel cylinder 4. Under normal use and under E1 earthquake conditions, the shear pin 6 and the friction between the steel cylinder 4 and the support base plate 2 work together to limit the displacement of the support top plate 1, thereby preventing large displacement of the main beam and affecting the normal use of the bridge.

[0092] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A bridge seismic isolation bearing, characterized in that: The invention comprises a support top plate (1), a support bottom plate (2), a hollow spherical plate (3) and a steel cylinder (4); the hollow spherical plate (3) is mounted on the top of the steel cylinder (4); the support top plate (1) is slidably arranged on the hollow spherical plate (3); and the support top plate (1) can form a first limit between the support top plate (1) and the hollow spherical plate (3); and the steel cylinder (4) is mounted on the support bottom plate (2) via a shear pin (6).

2. A bridge seismic isolation bearing according to claim 1, characterized in that: The bottom of the steel cylinder (4) is provided with a mounting groove (41), the support base plate (2) is provided with a mounting hole (21), one end of the shear pin (6) is installed in the mounting groove (41), and the other end of the shear pin (6) is placed in the mounting hole (21).

3. The bridge seismic isolation bearing according to claim 2, characterized in that: The mounting grooves (41) are arranged in a circular array at the bottom of the steel cylinder (4); The mounting holes (21) are arranged at annular intervals on the support base plate (2).

4. The bridge seismic isolation bearing according to claim 1, characterized in that: The bearing capacity of the shear pin (6) is smaller than the bearing capacity of the steel cylinder (4).

5. A bridge seismic isolation bearing according to any one of claims 1 to 4, characterized in that: The colloid support (5) is provided inside the steel cylinder (4), wherein the top of the colloid support (5) is provided with an upper connecting plate (20) connected to the support top plate (1), and the bottom of the colloid support (5) is provided with a lower connecting plate (30) connected to the support bottom plate (2), and the upper connecting plate (20) can abut against the hollow spherical plate (3) to form the first limit.

6. The bridge seismic isolation bearing according to claim 5, characterized in that: The steel cylinder (4) can abut against the support base plate (2) to form a second limit.

7. The bridge seismic isolation bearing according to claim 6, characterized in that: It also includes a planar annular slide plate (7), which is installed on the top of the hollow spherical plate (3), and the support top plate (1) is in contact with the planar annular slide plate (7).

8. The bridge seismic isolation bearing according to claim 7, characterized in that: It also includes a spherical annular slide plate (8), which is installed on the top of the steel cylinder (4), and the hollow spherical plate (3) is in contact with the spherical annular slide plate (8).

9. The bridge seismic isolation bearing according to claim 5, characterized in that: A pin shaft (9) is provided on the upper connecting plate (20), and the pin shaft (9) is inserted into the support top plate (1).

10. The bridge seismic isolation bearing according to claim 5, characterized in that: The lower connecting plate (30) is connected to the support base plate (2) via fixing bolts (10).

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