Shock absorption and isolation support for beam bridge

Abstract

The utility model discloses a shock absorption and isolation support for a beam bridge, which comprises a lower connecting steel plate, a supporting block positioned on the upper surface of the lower connecting steel plate, and an upper connecting steel plate positioned on the top surface of the supporting block, and when the shock absorption support is in a use state, the shock absorption support is positioned between a beam body and a support pad stone; the lower connecting steel plate is placed on the upper surface of the support pad stone, bolt holes are formed in the portions, not covered with the supporting blocks, of the lower connecting steel plate, the lower connecting steel plate is fixed to the support pad stone through bolts, two L-shaped side plates are arranged on the upper surface of the upper connecting steel plate, and the beam body is located between the two L-shaped side plates. The shock absorption and isolation support is convenient to replace, the support can be rapidly replaced after an earthquake, in the process of replacing the support, the beam body and the support are connected through the L-shaped side plates and the bolts, steel bars do not need to be planted at the bottom of the beam body, and therefore the jacking space of the beam body is reduced, rapid replacement of the support in the limited space is achieved, the bridge repairing efficiency after the earthquake is improved, and the service life of the support is prolonged. And precious time is won for rescue after disasters.

Description

Technical Field

[0001] The utility model relates to the field of bridge building structures, in particular to a seismic isolation support for a beam bridge which can be conveniently replaced in an extremely restricted space after an earthquake. Background Art

[0002] The bridge bearing is an important structural component connecting the upper and lower structures of the bridge. It is located between the bridge and the pad stone. It can reliably transfer the load and deformation, including displacement and rotation, borne by the upper structure of the bridge to the lower structure of the bridge. It is an important force transmission device of the bridge. The functions of the bridge bearing are mainly in three aspects: the first is to reliably transfer the dead load and live load of the upper structure to the pier, and at the same time bear the horizontal displacement, rotation and other deformations of the structure end caused by the load; the second is to adapt to the expansion and contraction deformation of the structure caused by environmental changes such as temperature and humidity; the third is to resist the structural translation caused by wind force, seismic waves, etc., and reduce the adverse effects of vibration on the structure.

[0003] Medium and small span beam bridges generally use low-cost plate rubber bearings, which are generally placed directly between the pier pad stone and the embedded steel plate at the bottom of the beam without any other connection treatment. Among the many types of earthquake damage, plate rubber bearings are extremely common, with an earthquake damage rate of 16.6%. The main reasons are that the bearing design does not fully consider the requirements of earthquake resistance, the structural connection and support measures are insufficient, and some bearing forms and materials are defective. The main forms of damage are the pull-out and shearing of the bearing anchor bolts, the fall-off of the movable bearing, and the structural damage of the bearing itself.

[0004] Rapid replacement of bearings after an earthquake and rapid restoration of traffic are of great significance to ensure the rapid implementation of emergency rescue work and the normal operation of highways, and to reduce earthquake hazards. The height of ordinary plate bearings for existing conventional beam bridges, especially for T-beams, I-beams, and rectangular cross-section beams, is about 5 cm. In the existing technology, the replacement of bridge bearings requires bolt drilling and rebar planting at the bottom of the beam and the bearing pad stone, which is limited in space and difficult to construct. Conventional rebar planting at the bottom of the beam requires the entire beam to be lifted by more than 50 cm, which has a high risk of lifting and is difficult to drill holes for rebar planting, making it difficult to replace bridge bearings. Utility Model Content

[0005] The utility model aims to provide a seismic isolation bearing for a beam bridge which can be easily replaced in an extremely confined space after an earthquake, so as to solve the problem of difficulty in constructing and repairing beam bridge bearings in the case of limited construction space after an earthquake.

[0006] In order to achieve the above objectives, the technical solution of the utility model is:

[0007] A seismic isolation bearing for a beam bridge, the bearing comprising a lower connecting steel plate, a supporting block located on the upper surface of the lower connecting steel plate, and an upper connecting steel plate located on the top surface of the supporting block. When the seismic isolation bearing is in use, the seismic isolation bearing is located between the beam body and the supporting pad stone, the lower connecting steel plate is placed on the upper surface of the supporting pad stone, bolt holes are provided on the portion of the lower connecting steel plate not covered by the supporting block, the lower connecting steel plate is fixed to the supporting pad stone by bolts, two L-shaped side plates are provided on the upper surface of the upper connecting steel plate, and the beam body is located between the two L-shaped side plates.

[0008] Furthermore, the lower connecting steel plate and the upper connecting steel plate are rectangular steel plates, and the supporting block is arranged between the lower connecting steel plate and the upper connecting steel plate.

[0009] Furthermore, the length of the support block is smaller than the length of the lower connecting steel plate and smaller than the length of the upper connecting steel plate, the support block is located in the middle of the lower connecting steel plate or the upper connecting steel plate, and the support block is a cuboid, a cube or a cylinder.

[0010] Furthermore, the L-shaped side plate includes a horizontal plate and a vertical plate, the length of the horizontal plate is equal to the width of the upper connecting steel plate, the horizontal plate is placed at the end of the upper surface of the upper connecting steel plate, and a plurality of bolt holes are preset on the horizontal plate and the upper connecting steel plate, and the horizontal plate is fixed to the upper connecting steel plate by bolts.

[0011] Furthermore, the vertical plate of the L-shaped side plate is in close contact with the surface of the beam body, bolt holes are arranged on the vertical plate, and the vertical plate is fixed to the beam body by bolts.

[0012] Furthermore, a plurality of stiffening plates may be arranged at intervals between the horizontal plate and the vertical plate of the L-shaped side plate.

[0013] Furthermore, the stiffening plate is a right triangle or a right trapezoid, the stiffening plate and the beam body are respectively located on both sides of the vertical plate of the L-shaped side plate, the stiffening plate and the L-shaped side plate are integrally formed, the vertical edge of the stiffening plate is connected to the vertical plate of the L-shaped side plate, and the bottom end of the stiffening plate is connected to the horizontal plate of the L-shaped side plate.

[0014] The beneficial effects of the utility model are:

[0015] 1. The seismic isolation bearing of the utility model is easy to replace and can be quickly replaced after an earthquake. During the replacement of the bearing, the beam and the bearing are connected by L-shaped side plates and bolts, and there is no need to embed reinforcement on the bottom of the beam. Since there is no need to embed reinforcement on the bottom of the beam, the lifting space of the beam is reduced, which enables rapid replacement of bearings in confined spaces, improves the efficiency of post-earthquake bridge repair and traffic restoration, and buys valuable time for post-disaster rescue.

[0016] 2. The utility model is easy to construct. The steel plates and stiffening ribs are prefabricated components and can be connected only by bolts, which is convenient for assembly construction.

[0017] 3. Compared with the plate-type rubber bearings in the prior art, the seismic isolation bearings of the utility model add horizontal upper and lower connecting steel plates, which can effectively dissipate seismic forces, greatly reduce the transmission of horizontal forces to the lower structure, reduce the risk of damage caused by overload of the lower structure, and improve the overall seismic performance of the bridge. The utility model can reduce the probability of damage to the bearings due to earthquakes and the difficulty of maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the prior art.

[0019] Figure 2 It is a schematic diagram of the utility model of the seismic isolation bearing being located between the beam body and the bearing pad stone.

[0020] Figure 3 It is a schematic diagram of the utility model for implanting the lower connecting steel plate bolts.

[0021] Figure 4 This is a schematic diagram of the bolts implanted into the side of the beam body according to the utility model.

[0022] Figure 5 This is a schematic diagram of the utility model in which a beam body is connected to an L-shaped side plate by bolts.

[0023] Figure 6 It is a schematic diagram of the dimensions of the seismic isolation bearing used in the force analysis in the specific embodiment of the present utility model.

[0024] Among them: lower connecting steel plate 1; supporting block 2; upper connecting steel plate 3; beam body 4; support pad stone 5; bolt hole 6; bolt 7; L-shaped side plate 8; stiffening plate 9; original damaged support A. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model is further described below with reference to the accompanying drawings.

[0026] like Figure 2 and Figure 3As shown, the utility model of the seismic isolation bearing for beam bridge includes a lower connecting steel plate 1, a supporting block 2 located on the upper surface of the lower connecting steel plate 1, and an upper connecting steel plate 3 located on the top surface of the supporting block 2; the lower connecting steel plate 1 and the upper connecting steel plate 3 are generally rectangular steel plates, the supporting block 2 is arranged between the lower connecting steel plate 1 and the upper connecting steel plate 3, the length of the supporting block 2 is less than the length of the lower connecting steel plate 1 and less than the length of the upper connecting steel plate 3, and the supporting block 2 is located in the middle part of the lower connecting steel plate 1 or the upper connecting steel plate 3; the supporting block 2 can be a cuboid, a cube or a cylinder, and the material of the supporting block 2 can be lead core or rubber clamped steel plate according to actual conditions.

[0027] When the seismic isolation support is in use, the seismic isolation support is located between the beam body 4 and the support pad 5. The lower connecting steel plate 1 is placed on the upper surface of the support pad 5, and bolt holes 6 are set in the part of the lower connecting steel plate 1 that is not covered by the support block 2. The lower connecting steel plate 1 is fixed to the support pad 5 by bolts 7. Figure 4 and Figure 5 As shown, two L-shaped side plates 8 are arranged on the upper surface of the upper connecting steel plate 3, wherein one L-shaped side plate 8 is located on one side of the beam body 4, and the other L-shaped side plate 8 is located on the other side opposite to the beam body 4, and the beam body 4 is located between the two L-shaped side plates 8. The L-shaped side plate 8 includes a horizontal plate and a vertical plate, the length of the horizontal plate is equal to the width of the upper connecting steel plate 3, the horizontal plate is placed at the end of the upper surface of the upper connecting steel plate 3, and the horizontal plate is fixed to the upper connecting steel plate 3 by bolts 7, and a plurality of bolt holes 6 can be pre-arranged on the horizontal plate and the upper connecting steel plate 3 to facilitate fixing the horizontal plate of the L-shaped side plate to the upper connecting steel plate 3 by bolts 7; the vertical plate of the L-shaped side plate 8 is close to the surface of the beam body 4, the vertical plate is provided with bolt holes 6, and the vertical plate is fixed to the beam body 4 by bolts 7.

[0028] A plurality of stiffening plates 9 may be arranged between the horizontal plate and the vertical plate of the L-shaped side plate 8. The stiffening plates 9 may be in the shape of a right triangle or a right trapezoid. The stiffening plates 9 and the beam body 4 are respectively located on both sides of the vertical plate included in the L-shaped side plate 8. The stiffening plates 9 may be integrally formed with the L-shaped side plate 8. The vertical edges of the stiffening plates 9 are connected to the vertical plates of the L-shaped side plates, and the bottom ends of the stiffening plates 9 are connected to the horizontal plates of the L-shaped side plates.

[0029] The L-shaped side panel 8 and the upper connecting steel plate 3 can be formed as one piece, or the horizontal plate of the L-shaped side panel can be fixed to the upper connecting steel plate 3 by bolts 7; preferably, the L-shaped side panel 8 and the upper connecting steel plate 3 are fixed by bolts, so that the position of the L-shaped side panel 8 on the upper connecting steel plate 3 can be flexibly adjusted, so that the seismic isolation bearing can adapt to beams 4 of different sizes.

[0030] A method for replacing seismic isolation bearings of a beam bridge in an extremely confined space after an earthquake; after an earthquake, the bridge is inspected, and if a bearing is found to be significantly damaged or deformed, the damaged bearing is marked and replaced, specifically comprising the following steps:

[0031] S1: Drilling

[0032] According to the bolt holes required on the bearing pad stone 5 after the seismic isolation bearing is installed, on-site layout is carried out and holes are drilled at the corresponding locations.

[0033] The bolt holes required on the beam body 4 after the seismic isolation bearing is installed are laid out on site, and holes are drilled at the corresponding locations.

[0034] S2: Beam lifting

[0035] Use a jack to lift the beam body 4 as a whole by 20 cm; the lifting height is sufficient to replace the support height, and the small lifting height means small construction risk.

[0036] S3: Remove the original damaged bearing A and replace the seismic isolation bearing

[0037] After removing the original damaged bearing A, place the seismic isolation bearing on the bearing pad stone 5.

[0038] S4: Remove the jack and place the beam body 4 on the upper connecting steel plate 3.

[0039] S5: Implant bolt

[0040] Bolts are implanted on the lower connecting steel plate to fix the lower connecting steel plate 1 to the support pad stone 5; there are multiple bolt holes reserved on the horizontal plate of the L-shaped side plate and the upper connecting steel plate 3, and the horizontal plate of the L-shaped side plate and the upper connecting steel plate 3 are pre-tightened by bolts. At this time, the bolts between the horizontal plate of the L-shaped side plate and the upper connecting steel plate 3 are not completely tightened; there are multiple bolt holes reserved on the vertical plate of the L-shaped side plate, and holes are drilled at the positions corresponding to the reserved bolt holes of the vertical plate of the L-shaped side plate on the side of the beam body, and the vertical plate of the L-shaped side plate is fixed to the beam body 4 by bolts; the bolts between the horizontal plate of the L-shaped side plate and the upper connecting steel plate are tightened to firmly fix the L-shaped side plate and the upper connecting steel plate.

[0041] S6: Anti-corrosion coating of steel plates on seismic isolation bearings.

[0042] Anti-corrosion coatings, such as fluorocarbon topcoat, epoxy zinc-rich primer, inorganic anti-corrosion coatings, etc., may be applied to the lower connecting steel plate, the upper connecting steel plate and the L-shaped side plate.

[0043] In the present utility model, the design principle of the seismic isolation bearing is to first determine the type and model of the seismic isolation bearing to be used based on calculations, and then determine the size and specific arrangement of the steel plate and stiffening plate, the bolt model and spacing based on the maximum horizontal force that the bearing can withstand under earthquake action.

[0044] After the specific size and layout of the seismic isolation bearing are determined, the model and height of the lifting jack are determined according to the vertical force and size of the bearing, and holes are drilled at the corresponding bolt positions on the top and side of the pier cap beam to facilitate the subsequent bolt assembly.

[0045] When replacing the bearing, lift the beam top by about 20cm, take out the original plate-type rubber bearing, and replace it with the utility model's seismic isolation bearing. At the same time, it is necessary to drill holes corresponding to the reserved bolt holes in the lower connecting steel plate on the top of the pier cap beam, and drill holes corresponding to the reserved bolt holes on the vertical plate of the L-shaped side plate on the side of the beam. Multiple corresponding bolt holes can be pre-set on the horizontal plate of the L-shaped side plate and the upper connecting steel plate. The positions of all bolt holes must be accurately laid out, and the error must be controlled within 2mm to prevent the seismic isolation bearing from causing installation difficulties due to excessive errors.

[0046] After the bearing is replaced, remove the jack device and insert the lower connecting steel plate bolts one by one in the reserved bolt holes. The bolts on the lower connecting steel plate ensure that the seismic isolation bearing is tightly connected to the bearing pad stone. Insert the side bolts of the beam body and tighten them to ensure that the beam body is tightly connected to the L-shaped side plate steel plate. Use bolts to connect the vertical plate of the L-shaped side plate to the beam body, and use bolts to connect the horizontal plate of the L-shaped side plate to the upper connecting steel plate to ensure that the bearing is tightly connected to the beam body, effectively transmitting the horizontal force generated by the beam body under the action of the earthquake to the bearing.

[0047] As another embodiment of the present invention, bolt reserved holes can be drilled on the support pedestal 5 and the beam 4 according to the size of the lower connecting steel plate 1 and the reserved positions of the bolt holes on the upper connecting steel plate 3, the size of the L-shaped side plate and the positions of the reserved bolt holes on the L-shaped side plate, and the size of the beam body, and then the beam body is lifted, the seismic isolation support is replaced, the lower connecting steel plate and the side bolts of the beam body are implanted, the lower connecting steel plate and the support pedestal are bolted, the vertical plate of the beam body and the L-shaped side plate are bolted, and the horizontal plate of the L-shaped side plate and the upper connecting steel plate are bolted. After all the damaged supports are installed and replaced, the road is restored to normal.

[0048] by Figure 6The reliability analysis of the bearing connection of the specific embodiment of the utility model is carried out. The maximum horizontal force Fmax of the bearing is 549KN after earthquake resistance calculation, and the strength and stiffness of the connection are simulated and analyzed. The analysis uses the finite element software ANSYS Workbench, ignoring the friction between the beam and the steel plate, the anchor hole is consolidated with the beam, the pre-tightening force of the connecting bolt is 225KN, the connecting bolt uses M24 bolts, and the friction coefficient between the steel plates is 0.15; Figure 6 The unit of each dimension is millimeter.

[0049] (1) Longitudinal bridge direction

[0050] A force of 549KN is applied to the seismic isolation bearing, and the force acts on the connecting steel plate on the seismic isolation bearing in the longitudinal direction of the bridge.

[0051] (2) Transverse bridge toward the bolt side

[0052] A force of 549 kN is applied to the seismic isolation bearing, and the force acts on the connecting steel plate on the seismic isolation bearing in the direction along the transverse direction of the bridge toward the bolt side.

[0053] (3) The cross bridge faces the welding side

[0054] A force of 549KN is applied to the seismic isolation bearing, and the force acts on the connecting steel plate on the seismic isolation bearing in the direction along the transverse direction of the bridge toward the welding side.

[0055] Under different working conditions, the maximum equivalent effect of the seismic isolation bearing is less than the yield strength of material Q345B, 345MPa. Only the bolt connection has partial stress concentration due to the preload, and the stress in other parts is mostly below 100Mpa. The maximum deformation under each working condition is less than 1mm, so the reliability of the seismic isolation bearing connection meets the requirements.

[0056] During design, the size of the steel plate stiffener and the type of bolts can be adjusted according to the actual needs of the project, so that it will not be damaged under a specific horizontal load and the reliability of the connection meets the requirements.

[0057] Finally, it should be noted that the contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field. The above description is only the preferred embodiment of the utility model and is not used to limit the utility model. Although the utility model is described in detail with reference to the above embodiments, for those skilled in the art, they can still modify the technical solutions recorded in the above embodiments, or replace some of the technical features therein with equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A seismic isolation bearing for a beam bridge, characterized in that: The support comprises a lower connecting steel plate (1), a supporting block (2) located on the upper surface of the lower connecting steel plate (1), and an upper connecting steel plate (3) located on the top surface of the supporting block (2). When the seismic isolation support is in use, the seismic isolation support is located between the beam body (4) and the support pad stone (5). The lower connecting steel plate (1) is placed on the upper surface of the support pad stone (5). Bolt holes (6) are provided at the portion of the lower connecting steel plate (1) not covered by the supporting block (2). The lower connecting steel plate (1) is fixed to the support pad stone (5) by bolts (7). Two L-shaped side plates (8) are provided on the upper surface of the upper connecting steel plate (3), and the beam body (4) is located between the two L-shaped side plates (8).

2. The seismic isolation bearing for a beam bridge according to claim 1, characterized in that: The lower connecting steel plate (1) and the upper connecting steel plate (3) are rectangular steel plates, and the supporting block (2) is arranged between the lower connecting steel plate (1) and the upper connecting steel plate (3).

3. The seismic isolation bearing for a beam bridge according to claim 2, characterized in that: The length of the support block (2) is smaller than the length of the lower connecting steel plate (1) and smaller than the length of the upper connecting steel plate (3); the support block (2) is located in the middle of the lower connecting steel plate (1) or the upper connecting steel plate (3); the support block (2) is a rectangular parallelepiped, a cube or a cylinder.

4. The seismic isolation bearing for a beam bridge according to claim 1, characterized in that: The L-shaped side plate (8) includes a horizontal plate and a vertical plate. The length of the horizontal plate is equal to the width of the upper connecting steel plate (3). The horizontal plate is placed at the end of the upper surface of the upper connecting steel plate (3). A plurality of bolt holes (6) are preset on the horizontal plate and the upper connecting steel plate (3). The horizontal plate is fixed to the upper connecting steel plate (3) by bolts (7).

5. The seismic isolation bearing for a beam bridge according to claim 1, characterized in that: The vertical plate of the L-shaped side plate (8) is in close contact with the surface of the beam body (4), bolt holes (6) are provided on the vertical plate, and the vertical plate and the beam body (4) are fixed by bolts (7).

6. The seismic isolation bearing for a beam bridge according to claim 1, characterized in that: A plurality of stiffening plates (9) may be arranged at intervals between the horizontal plate and the vertical plate of the L-shaped side plate (8).

7. The seismic isolation bearing for a beam bridge according to claim 6, characterized in that: The stiffening plate (9) is a right triangle or a right trapezoid. The stiffening plate (9) and the beam body (4) are respectively located on both sides of the vertical plate of the L-shaped side plate (8). The stiffening plate (9) and the L-shaped side plate (8) are integrally formed. The vertical edge of the stiffening plate (9) is connected to the vertical plate of the L-shaped side plate, and the bottom end of the stiffening plate (9) is connected to the horizontal plate of the L-shaped side plate.

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