An isotropic full-reset repair-free seismic isolation bearing

Abstract

The present application relates to the field of bridge structure or building technology, and more particularly to an isotropic full-reset repair-free seismic isolation support. The support comprises an upper seat plate, a middle seat plate, a convex slope seat plate, a concave slope body and a lower seat plate; four convex slope bodies are symmetrically arranged below the convex slope seat plate along two diagonal lines, the intersection line of the slopes of the two convex slope bodies on one diagonal line is in the shape of a cross, and the intersection line of the slopes of the two convex slope bodies on the other diagonal line is in the shape of a cross; four concave slope bodies are arranged above the lower seat plate and correspond to the convex slope bodies below, and a slope friction pair is arranged between the convex slope and the concave slope. The starting force of the support remains consistent when moving in any horizontal direction, and the isotropic seismic isolation performance is achieved; the seismic energy is dissipated through the sliding friction of the slope friction pair during an earthquake, and the upper structure automatically returns to the center position along the slope direction by the component force of the gravity after the earthquake, and full reset is achieved.

Description

Technical Field

[0001] This invention relates to the field of bridge structure or building technology, and more specifically, to an isotropic, fully repositionable, repair-free seismic isolation bearing. Background Technology

[0002] In bridge engineering in high-intensity earthquake zones, seismic isolation bearings are core components that cut off the transmission of seismic energy to the upper structure and protect the main body of the piers and beams. In recent years, the concept of bridge seismic resistance has been evolving from "bearing capacity design" to the resilient goal of "functional recovery". The industry's requirements for bearings are no longer limited to energy dissipation and vibration reduction, but have been further extended to comprehensive performance such as accurate self-resetting after earthquakes, low damage, and easy repair.

[0003] However, existing seismic isolation bearings still have significant shortcomings in post-earthquake reset. For example, hyperboloid spherical seismic isolation bearings have residual displacement after an earthquake, making it difficult to reset completely. Although some solutions have attempted to reduce residual displacement by adding auxiliary reset devices such as springs and shape memory alloys, it is still difficult to completely eliminate it.

[0004] To address the aforementioned reset challenge, existing technologies have introduced inclined plane-guided self-resetting structures. For example, existing patent CN201362821Y discloses a bridge seismic isolation movable bearing, in which the contact surface between the lower support plate and the lower swing member is a V-shaped inclined plane, with the two inclined planes of the V-shaped plane being symmetrical along the transverse direction of the bridge. The lower support plate and the lower swing member achieve unidirectional self-resetting through the cooperation of the transverse V-shaped inclined plane, but in the longitudinal direction of the bridge, it can only meet the conventional telescopic sliding requirements and cannot achieve seismic isolation and self-resetting in any direction within the horizontal plane.

[0005] To overcome the technical limitations of unidirectional self-reset, existing patent CN121295606A discloses a bridge resilient seismic isolation bearing, which includes an upper bearing plate, a middle bearing plate, a lower bearing plate, and a base plate. The lower bearing plate has a frustum-shaped protrusion at its bottom, and the base plate has a frustum-shaped groove. The two work together, and energy-dissipating friction pairs are set between the four inclined surfaces, theoretically enabling seismic isolation and self-reset in any direction. However, in practical applications, this integral frustum structure still has the following technical drawbacks:

[0006] Firstly, the seismic isolation and damping performance varies across different directions. This bearing employs an integral truncated pyramid structure, with the intersection of adjacent inclined planes at 45°, meaning its edges are located diagonally, forming an "X" shape. Based on this geometric characteristic, the sliding resistance and starting force are lowest in the diagonal direction (45°); while in the longitudinal and transverse bridge directions (0° / 90°), a single inclined plane must be ascended, resulting in the highest sliding resistance and starting force. This anisotropic mechanical characteristic leads to inconsistent hysteresis curves and differences in horizontal forces in different directions, necessitating consideration of directional differences in seismic calculations and design, increasing design complexity. Furthermore, due to the lower starting force in the 45° direction, this direction is more prone to significant slippage under seismic loads. Therefore, seismic design requires a larger allowance for post-earthquake displacement to accommodate the oblique seismic response, resulting in increased bearing travel and beam end clearance.

[0007] Secondly, the support stability is insufficient. The lower plate and the base plate of this bearing are a single integral truncated quadrangular mating structure. When the bearing moves along the longitudinal or transverse direction of the bridge, the lower plate slides alternately on the left and right or front and back inclined surfaces, meaning that there is always only one inclined surface support in one direction. Under extreme conditions where vertical earthquakes cause the ballast to disappear, the anti-overturning capacity is insufficient, and the bearing is at risk of overturning. Summary of the Invention

[0008] In view of this, the present invention aims to propose an isotropic, fully reset, repair-free seismic isolation bearing to solve the following problems existing in the prior art:

[0009] (1) The existing seismic isolation bearings have significant differences in mechanical properties in different directions of motion, and their anisotropy is prominent. Seismic design needs to take into account the differences in direction, which increases the design difficulty and engineering cost.

[0010] (2) Existing seismic isolation bearings have residual displacement after the earthquake, which makes it difficult to fully reset or can only achieve self-resetting in a single direction, and cannot meet the requirements of seismic isolation and self-resetting in all directions under multidimensional seismic action.

[0011] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0012] This invention discloses an isotropic, fully reset, repair-free seismic isolation bearing, comprising:

[0013] Upper seat plate;

[0014] The middle seat plate is located below the upper seat plate, and the two can rotate relative to each other;

[0015] A convex ramp seat plate is located below the middle seat plate, and the two can slide relative to each other. Four convex ramp bodies are symmetrically arranged along the center of two diagonal lines below the convex ramp seat plate. The lower part of the convex ramp body is a convex quadrangular frustum structure with four convex inclined surfaces. Among them, the boundary line of the inclined surfaces of two convex ramp bodies on one diagonal line is a "+" shape in the top view, and the boundary line of the inclined surfaces of two convex ramp bodies on the other diagonal line is a "×" shape in the top view.

[0016] The lower seat plate has a concave ramp on its upper part. The number of concave ramps is the same as that of convex ramps, and they are respectively located directly below the convex ramps. The upper part of the concave ramp is a concave quadrangular frustum structure with four concave inclined surfaces. The concave inclined surfaces and the convex inclined surfaces above them can fit together, and there are inclined friction pairs between the fitting inclined surfaces.

[0017] Optionally, in the top-view direction, the two inclined planes arranged in a cross shape intersect parallel to the longitudinal and transverse directions of the bridge, respectively; the two inclined planes arranged in an X shape intersect at a 45° angle to the longitudinal and transverse directions of the bridge, respectively.

[0018] Optionally, the inclination angle of the convex inclined surface is the same as the inclination angle of the concave inclined surface directly below it.

[0019] Optionally, the inclined friction pair includes an energy-dissipating sliding plate disposed on the convex inclined surface and an inclined stainless steel sliding plate disposed on the concave inclined surface, wherein the energy-dissipating sliding plate and the inclined stainless steel sliding plate slide in cooperation.

[0020] Optionally, the energy-consuming skateboard can be a non-metallic skateboard or a metal skateboard.

[0021] Optionally, a spherical friction pair capable of relative rotation is provided between the upper seat plate and the middle seat plate. The spherical friction pair includes a spherical non-metallic sliding plate provided on the lower surface of the upper seat plate and a spherical stainless steel sliding plate provided on the upper surface of the middle seat plate.

[0022] Optionally, a planar friction pair capable of relative sliding is provided between the middle seat plate and the convex ramp seat plate. The planar friction pair includes a planar non-metallic sliding plate provided on the lower surface of the middle seat plate and a planar stainless steel sliding plate provided on the upper surface of the convex ramp seat plate.

[0023] Optionally, a permanent baffle is provided above the convex ramp seat plate along its circumference, and a vertical guide friction pair that can slide relative to the permanent baffle and the upper seat plate is provided.

[0024] Optionally, the vertical guide friction pair includes a non-metallic guide slide plate located on the outer side of the upper seat plate and a stainless steel guide slide plate located on the inner side of the permanent baffle.

[0025] Compared with existing technologies, the isotropic, fully repositionable, repair-free seismic isolation bearing of the present invention has the following advantages:

[0026] (1) Under normal working conditions, the bearing performs conventional functions such as vertical bearing, planar sliding and vertical rotation, which meets the daily operation requirements of the bridge. At this time, the energy-dissipating inclined friction pair only bears vertical ballast and does not slide or rotate relative to each other, which does not affect the normal performance of the bearing.

[0027] (2) When the horizontal seismic force on the support is less than the starting force of the support, the inclined friction pair relies on static friction self-locking to maintain relative stillness and plays a reliable horizontal limiting role.

[0028] (3) When the seismic force on the support exceeds the starting force, the energy-dissipating inclined friction pair begins to slide back and forth, dissipating the seismic energy through the frictional resistance of the sliding surface. Moreover, the energy-dissipating friction pair only participates in sliding during the earthquake, and its friction coefficient can exceed 0.07, which has a strong energy dissipation capacity.

[0029] (4) The bearing does not need to be equipped with any special limit device in the precise switching from normal working condition to seismic working condition. It can be achieved by relying on the "switch" formed by the inclined plane angle and friction. No part of the bearing breaks during the earthquake. No parts need to be replaced after the earthquake. It can be reused multiple times. The bridge can be restored to traffic without repair within the preset seismic working condition, which significantly improves the seismic toughness of the bridge.

[0030] (5) After the earthquake, the component of the self-weight of the upper structure of the support along the inclined plane overcomes the friction force to form a restoring force, driving the support to slide back to the center position completely. The reset process does not require any external intervention.

[0031] (6) When the support slides to the center position, it needs to transition from one energy-consuming friction pair to another, which will generate an impact. However, at this time, the energy-consuming slide plate is a non-metallic slide plate, which can be converted from no compression to compression, and the material properties play a good buffering role.

[0032] (7) The two types of convex slopes, namely the "+" and "×", are located on the diagonal lines of the convex slope seat plate and are arranged in a centrally symmetrical manner, so that the horizontal force of the support when sliding in any horizontal direction is consistent, thus achieving sufficient and consistent seismic isolation and energy dissipation effect under seismic input in any direction; at the same time, seismic calculation and design do not need to consider directional differences, which significantly reduces the design difficulty; and there is no need to reserve extra displacement space for oblique seismic response, making the support structure more compact.

[0033] (8) The support is provided with two sets of centrally symmetrical convex ramps, so that when the support slides in any horizontal direction, it is jointly supported by at least two sets of symmetrically distributed inclined friction pairs, resulting in uniform force and good structural stability. At the same time, the two sets of convex ramps are rigidly connected as one unit through the convex ramp seat plate. During the post-earthquake reset, the two convex ramps in the same group slide synchronously, which effectively solves the problem of reset failure caused by a single ramp jamming, and significantly improves the reliability of post-earthquake reset. Attached Figure Description

[0034] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0035] Figure 1 This is a top view of the assembly of the concave inclined body and the lower support plate in the support.

[0036] Figure 2 Another top view of the assembly of the concave ramp body and the lower seat plate in the support;

[0037] Figure 3 For the support along Figure 2 A schematic diagram of the transverse cross-sectional structure of the bridge in the AA direction;

[0038] Figure 4 For the support along Figure 1 Schematic diagram of the longitudinal cross-sectional structure of the bridge in the BB direction;

[0039] Figure 5 This is a bottom view of the convex inclined seat plate, sealing ring, and energy-dissipating slide plate assembly in the support.

[0040] Figure 6 A schematic diagram of a structure where the support is in a transverse bridge-direction seismic isolation sliding state;

[0041] Figure 7 A schematic diagram of a structure where the support is in a longitudinal bridge-direction seismic isolation sliding state;

[0042] Figure 8 This is a top view of the first concave inclined plane in the support;

[0043] Figure 9 This is a top view of the second concave slope in the support.

[0044] Explanation of reference numerals in the attached figures:

[0045] 1. Upper seat plate; 2. Spherical non-metallic sliding plate; 3. Spherical stainless steel sliding plate; 4. Middle seat plate; 5. Flat non-metallic sliding plate; 6. Flat stainless steel sliding plate; 7. Sealing ring; 8. Guide non-metallic sliding plate; 9. Guide stainless steel sliding plate; 10. Convex ramp seat plate; 101. Permanent baffle; 102. Convex ramp body; 11. Energy-dissipating sliding plate; 12. Sloping stainless steel sliding plate; 13. Concave ramp body; 131. First concave ramp body; 132. Second concave ramp body; 133. Third concave ramp body; 134. Fourth concave ramp body; 135. Sloping boundary line; 14. Lower seat plate. Detailed Implementation

[0046] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. In addition, the orientations involved in the following specific embodiments are briefly explained: the directions or positional relationships indicated by "front", "rear", "up", "down", "left", "right", "top", "bottom", etc. mentioned in the embodiments refer to the orientations or positional relationships shown in the accompanying drawings, and the term "on" means directly or indirectly supported by the element.

[0047] like Figures 1 to 9 As shown, the present invention provides an isotropic, fully reset, repair-free seismic isolation bearing, comprising:

[0048] Upper seat plate 1;

[0049] The middle seat plate 4 is located below the upper seat plate 1, and the two can rotate relative to each other;

[0050] A convex ramp seat plate 10 is located below the middle seat plate 4, and the two can slide relative to each other. Four convex ramp bodies 102 are symmetrically arranged along the center of two diagonal lines below the convex ramp seat plate 10. The lower part of the convex ramp body 102 is a convex quadrangular frustum structure with four convex inclined surfaces. Among them, the intersection line 135 of the inclined surfaces of two convex ramp bodies 102 on one diagonal line is a "+" shape in the top view, and the intersection line 135 of the inclined surfaces of two convex ramp bodies 102 on the other diagonal line is a "×" shape in the top view.

[0051] The lower seat plate 14 has a concave ramp 13 on its upper part. The number of concave ramps 13 is the same as that of convex ramps 102, and they are respectively located directly below the convex ramps 102. The upper part of the concave ramp 13 is a concave quadrangular frustum structure with four concave ramps. The concave ramps and the convex ramps above them can fit together, and there are ramp friction pairs between the fitting ramps.

[0052] Based on the aforementioned structure of the convex ramp 102 and concave ramp 13, the support is supported by the same number and spatially related ramps when moving in any horizontal direction. The horizontal climbing force remains consistent in all directions, eliminating directional differences and achieving isotropic seismic isolation and damping performance. This effectively avoids weak points in seismic resistance caused by uncertain earthquake incident directions. Simultaneously, the four concave ramps 13 correspond one-to-one with the four convex ramps 102 and are respectively positioned directly below the convex ramp 102, forming a multi-point support structure symmetrically distributed circumferentially, ensuring the support can withstand any direction. The structure is uniformly stressed and stably supported during movement. The concave and convex inclined surfaces are in close contact with each other, and an inclined friction pair is provided between the contact surfaces. This allows the convex inclined slope 102 to slide along the concave inclined surface of the concave inclined slope 13 under seismic action. The frictional resistance of the inclined friction pair dissipates the seismic energy and prolongs the natural vibration period of the structure. After the earthquake, the component of the self-weight of the upper structure of the support along the inclined surface overcomes the frictional force of the inclined friction pair and drives the convex inclined slope 102 to return to the center position of the concave inclined slope 13, achieving complete reset and significantly reducing the residual displacement after the earthquake. This is conducive to the rapid restoration of bridge traffic after the earthquake.

[0053] More specifically, the upper part of the convex ramp 102 is a cylindrical structure, and its top is fixedly connected to or integrally formed with the lower surface of the convex ramp base plate 10; the lower part of the convex ramp 102 is a four-sided convex truncated pyramid structure, with the four convex faces evenly distributed around the central axis of the convex ramp 102. The lower part of the concave ramp 13 is a cylindrical structure, and its bottom is fixed to or integrally formed with the lower base plate 14; the upper part of the concave ramp 13 is a four-sided concave truncated pyramid structure, with the four concave faces evenly distributed around the central axis of the concave ramp 13.

[0054] Preferably, the bottom cylinder of the concave ramp 13 is connected to the lower base plate 14 via a keyway to restrict the rotation of the concave ramp 13 relative to the lower base plate 14; the convex ramp 102 is fixed to the lower surface of the convex ramp base plate 10 by bolt connection or keyway connection, which facilitates processing and replacement; the inclination angle of the concave ramp is consistent with the inclination angle of the convex ramp directly above it to ensure that the two are in complete surface contact under normal conditions, avoiding stress concentration caused by line contact or point contact, and making the support uniformly stressed under normal load; at the same time, the inclination angles of all convex ramps and all concave ramps are the same, so that the convex ramps 102 in the same group can slide back to the center position synchronously under the action of gravity component during the reset phase after the earthquake, and will not cause asynchronous reset or jamming due to angle differences.

[0055] It should be noted that "centrally symmetrical distribution" means that in the planar projection of the convex slope base plate 10 and the convex slope body 102, the center points of the four convex slope bodies 102 are evenly distributed on the circumference of the circle with the center of the convex slope base plate 10 as the center, and the included angle between the center points of adjacent convex slope bodies 102 is 90°; the arrangement of the four concave slope bodies 13 on the lower base plate 14 is the same as that of the four convex slope bodies 102, to ensure that the two correspond one-to-one in the vertical direction. "Directly below" means that the four convex slope bodies 102 and the four concave slope bodies 13 correspond one-to-one in the vertical direction, but during an earthquake, the convex slope body 102 will deviate from the directly below position after sliding relative to the concave slope body 13; "quadrangular frustum" refers to a pyramidal frustum with a rectangular and parallel bottom and top surface, and its sides are four isosceles trapezoidal inclined surfaces; "intersection line 135" refers to the intersection line of two adjacent inclined surfaces of the quadrangular frustum, which appears as a straight line in the top view projection.

[0056] Specifically, in the overhead view, the two inclined planes 135 arranged in a cross shape are parallel to the longitudinal and transverse directions of the bridge, respectively; the two inclined planes 135 arranged in an X shape form an angle of 45° with the longitudinal and transverse directions of the bridge, respectively.

[0057] With the above arrangement, the climbing horizontal force of the bearing remains consistent when sliding in any horizontal direction, the starting force is equal, and the hysteresis characteristics are consistent, thus achieving isotropic seismic isolation and damping performance. The bearing has no mechanically weak direction, and there is no need to reserve extra displacement space for earthquake input in a specific direction, which simplifies seismic design and calculation. At the same time, each convex slope 102 participates in sliding synchronously and bears the load uniformly when moving in any direction, and also synchronously returns to the center position after the earthquake, ensuring complete reset and improving the working reliability and durability of the bearing.

[0058] More specifically, such as Figure 8 and Figure 9 As shown, the slope boundary line 135 of the concave slope 13 appears as two perpendicular straight lines in the top view projection, which are respectively a "+" shape and an "X" shape. When it is a "+" shape, one slope boundary line 135 is parallel to the longitudinal direction of the bridge and the other is parallel to the transverse direction of the bridge. When it is an "X" shape, the two slope boundary lines 135 form an angle of 45° with the longitudinal direction of the bridge and the transverse direction of the bridge, respectively. The slope boundary line 135 of the convex slope 102 also has the same arrangement.

[0059] It should be noted that "longitudinal bridge direction (0°)" refers to the extension direction of the bridge, i.e. the direction of traffic, and "transverse bridge direction (90°)" refers to the horizontal direction perpendicular to the longitudinal bridge direction; when sliding on the inclined plane, the angle between the sliding direction of the convex slope 102 and the longitudinal bridge direction is θ, 0° < θ < 90° and 90° < θ < 180°.

[0060] For a four-plane friction pair consisting of a single convex slope 102 and its corresponding concave slope 13, given a fixed upper load, slope angle, and friction coefficient of the plane friction pair, when the convex slope 102 slides relative to the concave slope 13 in different directions, the starting force (climbing horizontal force) of the support has only two values: when the convex slope 102 slides along the slope boundary line 135, the climbing angle is smaller, and the corresponding starting force is F2; ​​when the convex slope 102 slides along other directions of the slope, the climbing angle is larger, and the corresponding starting force is F1, and F2 < F1. However, since relative sliding on the slope always preferentially occurs along the path with the larger climbing angle, in the actual sliding process, each plane friction pair participates in bearing the load in the state of F1.

[0061] Preferably, based on the above principles, according to Figure 1 The convex ramp 102 is set up as shown:

[0062] When the support moves along the longitudinal direction of the bridge (θ=0°), it slides back and forth on four concave surfaces: the concave surfaces b1 and d1 of the first concave slope 131 and the concave surfaces b3 and d3 of the third concave slope 133. The starting force of the support is 4F1.

[0063] When the support moves along the transverse direction of the bridge (θ=90°), it slides back and forth on four inclined surfaces: the inclined surfaces a1 and c1 of the first concave inclined slope 131 and the inclined surfaces a3 and c3 of the third concave inclined slope 133. The starting force of the support is 4F1.

[0064] When the support moves along the 45° direction, it slides back and forth on four inclined surfaces: the inclined surfaces a2 and c2 of the second concave inclined body 132 and the inclined surfaces a4 and c4 of the fourth concave inclined body 134. The starting force of the support is 4F1.

[0065] When the support moves along the 135° direction, it slides back and forth on four inclined surfaces: the inclined surfaces b2 and d2 of the second concave inclined body 132 and the inclined surfaces b4 and d4 of the fourth concave inclined body 134. The starting force of the support is 4F1.

[0066] When the support moves along the inclined plane and 0°<θ<45°, it slides back and forth on eight inclined planes: the inclined planes a1 and c1 of the first concave inclined plane 131, the inclined planes a2 and c2 of the second concave inclined plane 132, the inclined planes a3 and c3 of the third concave inclined plane 133, and the inclined planes a4 and c4 of the fourth concave inclined plane 134. The starting force of the support is 4F1.

[0067] When the support moves along the inclined plane and 45° < θ < 90°, it slides back and forth on eight inclined planes: the inclined planes b1 and d1 of the first concave inclined plane 131, the inclined planes a2 and c2 of the second concave inclined plane 132, the inclined planes b3 and d3 of the third concave inclined plane 133, and the inclined planes a4 and c4 of the fourth concave inclined plane 134. The starting force of the support is 4F1.

[0068] When the support moves along the inclined plane and 90° < θ < 135°, it slides back and forth on eight inclined planes: the inclined planes b1 and d1 of the first concave inclined plane 131, the inclined planes b2 and d2 of the second concave inclined plane 132, the inclined planes b3 and d3 of the third concave inclined plane 133, and the inclined planes b4 and d4 of the fourth concave inclined plane 134. The starting force of the support is 4F1.

[0069] When the support moves along the inclined plane and 135° < θ < 180°, it slides back and forth on eight inclined planes: the inclined planes a1 and c1 of the first concave inclined plane 131, the inclined planes b2 and d2 of the second concave inclined plane 132, the inclined planes a3 and c3 of the third concave inclined plane 133, and the inclined planes b4 and d4 of the fourth concave inclined plane 134. The starting force of the support is 4F1.

[0070] The above results show that when the support reciprocates in any direction within the range of 0°≤θ≤180°, although the combination of the sliding concave and inclined surfaces changes with the direction, the starting force of the support remains constant at 4F1; similarly, the horizontal force when the support is on a downward slope also remains constant. Therefore, regardless of the direction from which the earthquake is input, the starting force, energy dissipation capacity, and recovery capacity of the support for triggering seismic isolation are the same, and the support exhibits isotropic performance under seismic loading.

[0071] Specifically, the bottom center plane of the convex slope 102 is the first center platform plane, and the upper center plane of the concave slope 13 is the second center platform plane.

[0072] It should be noted that when the support is in the fully reset state, the first central platform surface and the second central platform surface are directly opposite each other. The first central platform surface is the planar area at the center of the bottom of the convex slope 102, and the second central platform surface is the planar area at the center of the upper part of the concave slope 13. During an earthquake, the convex slope 102 slides relative to the concave slope 13 along the slope, and the first and second central platform surfaces are subsequently misaligned. After the earthquake, the component of the superstructure's self-weight along the slope direction drives the convex slope 102 back to the center position of the concave slope 13, and the first and second central platform surfaces return to their directly opposite state, at which point the support is fully reset.

[0073] Specifically, the inclined friction pair includes an energy-dissipating slide plate 11 disposed on the convex inclined surface and an inclined stainless steel slide plate 12 disposed on the concave inclined surface, with the energy-dissipating slide plate 11 and the inclined stainless steel slide plate 12 in sliding engagement.

[0074] When the seismic force exceeds the sum of the component of the self-weight of the superstructure along the inclined plane and the frictional force, the energy-dissipating sliding plate 11 and the inclined stainless steel sliding plate 12 reciprocate relative to each other. The seismic energy is dissipated through the frictional resistance of the sliding surface, and the natural vibration period of the structure is prolonged, thus achieving the effect of seismic isolation and vibration reduction. After the earthquake, the component of the self-weight of the superstructure along the inclined plane overcomes the frictional force to form a restoring force, so that the support is completely reset. At the same time, when the support slides to the center position, the energy-dissipating sliding plate 11 changes from an uncompressed state to a compressed state, and plays a good buffering role by utilizing the material properties, reducing the horizontal impact force transmitted to the pier.

[0075] More specifically, each convex surface of the convex ramp 102 is provided with a groove, and the energy-dissipating slide plate 11 is embedded and fixed in the groove; each concave surface of the concave ramp 13 is welded with a sloping stainless steel slide plate 12. The energy-dissipating slide plate 11 and the sloping stainless steel slide plate 12 form a sliding friction pair, and the contact surfaces of the two are both flat to ensure smooth sliding and uniform force distribution.

[0076] Preferably, each groove on the convex inclined surface is provided with a sealing ring 7 to prevent external impurities from entering the contact surface of the inclined friction pair, ensuring the working reliability and durability of the inclined friction pair; the energy-consuming sliding plate 11 is a non-metallic sliding plate or a metal sliding plate. The non-metallic sliding plate is a modified ultra-high molecular weight polyethylene sliding plate, whose surface is not coated with silicone grease, and the coefficient of friction can exceed 0.07; the metal sliding plate is a copper-based metal sliding plate, whose coefficient of friction is generally above 0.1.

[0077] It should be noted that modified ultra-high molecular weight polyethylene sliding plates have good self-lubrication and high wear resistance, making them suitable for small to medium earthquake conditions; copper-based metal sliding plates have a higher coefficient of friction and stronger energy dissipation capacity, making them suitable for strong earthquake conditions; according to the bridge's design bearing capacity and target energy dissipation requirements, energy-dissipating sliding plates 11 made of different materials can be selected to adjust the friction coefficient of the inclined friction pair, achieving customized design of the support's energy dissipation capacity. The inclined friction pair in this invention is an energy-dissipating component that only slides when the seismic force exceeds the starting force; under normal operating conditions, it is only subjected to vertical ballast and does not experience relative sliding or rotation.

[0078] Specifically, a spherical friction pair capable of relative rotation is provided between the upper seat plate 1 and the middle seat plate 4. The spherical friction pair includes a spherical non-metallic sliding plate 2 provided on the lower surface of the upper seat plate 1 and a spherical stainless steel sliding plate 3 provided on the upper surface of the middle seat plate 4.

[0079] The spherical contact type has automatic centering characteristics, flexible rotation and uniform force distribution, and can effectively transmit vertical loads and horizontal forces. By setting up spherical friction pairs, the bearing can adapt to the angular deformation of the bridge beam caused by temperature, load and other factors under normal working conditions, ensuring the structural safety of the bridge in operation. At the same time, the spherical rotation function is independent of and does not interfere with the planar sliding and inclined vibration isolation functions of the friction pairs below, ensuring the motion coordination of the bearing under multiple working conditions.

[0080] More specifically, the lower surface of the upper seat plate 1 is a concave spherical surface, and the spherical non-metallic sliding plate 2 is embedded in the concave spherical surface; the upper surface of the middle seat plate 4 is a convex spherical surface, and the spherical stainless steel sliding plate 3 is welded to the convex spherical surface. The two spherical surfaces have the same radius and fit together.

[0081] Preferably, the spherical non-metallic skateboard 2 is made of a polymer material with low friction coefficient and good wear resistance, and its surface is coated with silicone grease to reduce the friction coefficient and meet the needs of daily rotation and sliding.

[0082] It should be noted that during an earthquake, the spherical friction pair only serves to adapt to the deformation during rotation; it does not participate in horizontal limiting or energy dissipation. Horizontal energy dissipation and damping are mainly undertaken by the inclined friction pair below.

[0083] Specifically, a planar friction pair that can slide relative to each other is provided between the middle seat plate 4 and the convex ramp seat plate 10. The planar friction pair includes a planar non-metallic sliding plate 5 provided on the lower surface of the middle seat plate 4 and a planar stainless steel sliding plate 6 provided on the upper surface of the convex ramp seat plate 10.

[0084] The planar friction pair provides horizontal sliding freedom between the central bearing plate 4 and the convex inclined bearing plate 10, enabling the bearing to adapt to the expansion and contraction deformation of the bridge caused by temperature changes and concrete shrinkage and creep. Furthermore, the planar contact form ensures smooth sliding and low frictional resistance, meeting the displacement requirements under normal operating conditions. Simultaneously, the planar friction pair ensures that the inclined surface energy-dissipating sliding under seismic conditions and the planar displacement under normal operating conditions are independent. Normal displacement is borne by the planar friction pair, while seismic energy dissipation is borne by the inclined surface friction pair. This functional separation and non-interference ensures that the bearing can achieve its optimal performance under both normal operating and seismic conditions.

[0085] Preferably, the flat non-metallic sliding plate 5 is disposed on the lower surface of the middle seat plate 4, and the flat stainless steel sliding plate 6 is disposed on the upper surface of the convex ramp seat plate 10. The two are in planar contact, so as to achieve smooth sliding in any direction in the horizontal plane.

[0086] It should be noted that, in order to ensure a low coefficient of friction during sliding under normal operating conditions, the surface of the planar non-metallic sliding plate 5 is coated with silicone grease, which distinguishes it from the energy-dissipating sliding plate 11 below (which is not coated with silicone grease). The former meets the requirements for conventional low-friction sliding, while the latter meets the requirements for high-friction seismic energy dissipation. During strong earthquakes, the planar friction pair mainly provides the horizontal displacement degree of freedom, while the seismic isolation and energy dissipation work is mainly undertaken by the inclined friction pair below.

[0087] Specifically, a permanent baffle 101 is provided above the convex ramp seat plate 10 along its circumference. A vertical guide friction pair that can slide relative to the permanent baffle 101 and the upper seat plate 1 is provided. The vertical guide friction pair includes a guide non-metallic slide plate 8 provided on the outside of the upper seat plate 1 and a guide stainless steel slide plate 9 provided on the inside of the permanent baffle 101.

[0088] The vertical guiding friction pair between the permanent baffle 101 and the upper seat plate 1 constrains the displacement of the upper seat plate 1 in the transverse direction (limiting direction), effectively transferring the lateral horizontal load generated by the bridge superstructure to the substructure; in the longitudinal direction (movement direction), it allows the upper seat plate 1 to slide freely and provides sliding guidance. Under strong earthquake conditions, the convex slope 102 climbs upward along the slope of the concave slope 13, and the convex slope seat plate 10 drives the permanent baffle 101 to rise synchronously. At this time, the upper seat plate 1 and the permanent baffle 101 generate relative vertical sliding through the vertical guiding friction pair, releasing the vertical displacement constraint caused by the climbing, and avoiding additional internal stress or structural jamming of the support due to the obstruction of the climbing. At the same time, the permanent baffle 101 remains in contact with the upper seat plate 1 in the circumferential direction, restricting the relative horizontal misalignment between the upper seat plate 1 and the convex slope seat plate 10, effectively preventing the support from overturning or becoming unstable under strong earthquakes.

[0089] More specifically, a permanent baffle 101 is disposed around the perimeter of the convex ramp seat plate 10 and extends upward, with the lower part of the upper seat plate 1 extending into the space enclosed by the permanent baffle 101. In the transverse direction, a non-metallic guide slide plate 8 is embedded and fixed to the outer side of the upper seat plate 1, and a stainless steel guide slide plate 9 is welded and fixed to the inner side of the permanent baffle 101. The two slide together in the transverse direction to form a vertical guide friction pair. In the longitudinal direction, a displacement gap is left between the outer side of the upper seat plate 1 and the inner side of the permanent baffle 101. When a strong earthquake occurs, the convex ramp 102 climbs upward along the slope of the concave ramp 13, and the convex ramp seat plate 10 drives the permanent baffle 101 to rise synchronously. A relative sliding occurs between the non-metallic guide slide plate 8 and the stainless steel guide slide plate 9 in the vertical direction, which is consistent with the climbing direction.

[0090] It should be noted that "vertical" in the vertical guide friction pair means that the contact surface between the guide non-metallic slide plate 8 and the guide stainless steel slide plate 9 is a vertical plane, and the two form a sliding fit on this vertical plane.

[0091] The working principle of the support of this invention is as follows:

[0092] Normal operating conditions:

[0093] Under normal operating conditions, the inclined friction pair only bears vertical loads and does not experience relative sliding. In this state, the support performs its conventional functions such as vertical load bearing, planar sliding, and vertical rotation.

[0094] Minor earthquake conditions:

[0095] When the horizontal seismic force on the support is less than the support starting force (i.e., the resultant force of the component of the superstructure's self-weight along the inclined plane and the friction force of the inclined friction pair), the inclined friction pair relies on static friction self-locking to maintain relative stillness, playing a reliable horizontal limiting role, and the support does not enter the seismic isolation sliding state.

[0096] Moderate and strong earthquake conditions:

[0097] When the horizontal force of an earthquake reaches or exceeds the initiation force, the convex slope 102 overcomes the static friction resistance of the inclined surface friction pair and slides back and forth along the concave slope 13, and the support enters the seismic isolation and damping working state. For example... Figure 6 and Figure 7 As shown, during the sliding process, the beam rises along the inclined plane, converting seismic energy into gravitational potential energy. Simultaneously, the inclined plane friction pair dissipates seismic energy through frictional sliding and prolongs the structure's natural vibration period, effectively reducing seismic response. Since the four convex inclined planes 102 are distributed along two diagonal lines, and the inclined plane intersection lines 135 between the convex inclined planes on the same diagonal are arranged in a cross or X shape, the horizontal force climbing the support along any horizontal direction is 4F1, and the horizontal force descending is consistent, demonstrating isotropic seismic isolation and damping performance. Therefore, the maximum sliding displacement of the convex inclined plane 102 relative to the concave inclined plane 13 is D in both the transverse and longitudinal directions of the bridge. During the sliding process, the spherical friction pair between the upper seat plate 1 and the middle seat plate 4, and the planar friction pair between the middle seat plate 4 and the convex inclined plane seat plate 10, coordinate to adapt to horizontal displacement and rotation, ensuring coordinated movement of all components.

[0098] Post-earthquake recovery:

[0099] After the earthquake, the seismic force disappears, and the component of the bridge superstructure's self-weight along the inclined plane overcomes the static friction of the inclined plane friction pairs, forming a restoring force that drives the four convex ramp bodies 102 to slide synchronously back to the center position along the inclined plane. Since the four convex ramp bodies 102 are rigidly connected as one unit through the convex ramp seat plate 10, the four convex ramp bodies 102 slide synchronously during repositioning, and are supported simultaneously by at least four symmetrically distributed inclined plane friction pairs in any direction of sliding, ensuring uniform force distribution and complete repositioning of the supports without external intervention.

[0100] When sliding to the center position, the convex ramp 102 will generate an impact as it transitions from one inclined friction pair to another. However, at this time, the non-metallic sliding plate changes from uncompressed to compressed, and the material properties play a good buffering role. At the same time, due to the energy-dissipating friction, the horizontal force when the support goes downhill is low. Combining the above effects, the horizontal force transmitted to the pier can be reduced to a reasonable range.

[0101] In summary, this invention provides an isotropic, fully reset, repair-free seismic isolation bearing. This bearing features a middle bearing plate 4 and a convex ramp bearing plate 10 sequentially positioned between the upper bearing plate 1 and the lower bearing plate 14. Four convex ramps 102 are symmetrically arranged along two diagonal lines below the convex ramp bearing plate 10. Four concave ramps 13, corresponding one-to-one with the four convex ramps 102, are positioned on the lower bearing plate 14. The intersection line 135 of the inclined surfaces of two convex ramps 102 on one diagonal line forms a cross shape, while the intersection line 135 of the inclined surfaces of two convex ramps 102 on the other diagonal line forms an × shape. This ensures that the bearing can withstand movement in any horizontal direction. The horizontal forces for climbing are all 4F1, and the horizontal forces for descending are consistent, achieving isotropy. The inclined friction pair set between the convex and concave inclined surfaces keeps the support relatively stationary under normal operation and minor earthquake conditions to perform the limiting function. Under moderate and strong earthquake conditions, the energy is dissipated through the sliding friction of the inclined surfaces and the natural vibration period of the structure is extended. After the earthquake, the convex inclined body 102 is automatically driven to return to the center position by the component force of the superstructure's self-weight along the inclined surface direction, achieving complete reset. At the same time, the support does not require the installation of a limiting device, there is no component damage after the earthquake, and traffic can be restored without repair. It can be reused multiple times.

[0102] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various alterations and modifications without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. An isotropic, fully resettable, repair-free seismic isolation and damping bearing, characterized in that, include: Upper seat plate (1); The middle seat plate (4) is located below the upper seat plate (1), and the two can rotate relative to each other; A convex inclined plate (10) is located below the middle plate (4), and the two can slide relative to each other; Four convex ramps (102) are symmetrically arranged along the center of two diagonal lines below the convex ramp base plate (10). The lower part of the convex ramp (102) is a convex quadrangular frustum structure with four convex inclined surfaces. Among them, the intersection line (135) of the inclined surfaces of the two convex ramps (102) on one diagonal line is a "+" shape in the top view, and the intersection line (135) of the inclined surfaces of the two convex ramps (102) on the other diagonal line is a "×" shape in the top view. The lower seat plate (14) has a concave ramp (13) above it. The number of concave ramps (13) and convex ramps (102) is the same, and they are respectively located directly below the convex ramps (102). The upper part of the concave ramp (13) is a concave quadrangular frustum structure with four concave ramps. The concave ramps and the convex ramps above them can fit together, and there are ramp friction pairs between the fitting ramps.

2. The seismic isolation bearing according to claim 1, characterized in that, In the above-view direction, the two inclined planes (135) arranged in a cross shape are parallel to the longitudinal and transverse directions of the bridge, respectively; the two inclined planes (135) arranged in a × shape form an angle of 45° with the longitudinal and transverse directions of the bridge, respectively.

3. The seismic isolation bearing according to claim 1, characterized in that, The inclination angle of the convex inclined surface is the same as the inclination angle of the concave inclined surface that is directly below it.

4. The seismic isolation bearing according to claim 1, characterized in that, The inclined friction pair includes an energy-dissipating sliding plate (11) on the convex inclined surface and an inclined stainless steel sliding plate (12) on the concave inclined surface, with the energy-dissipating sliding plate (11) and the inclined stainless steel sliding plate (12) in sliding engagement.

5. The seismic isolation bearing according to claim 4, characterized in that, The energy-consuming skateboard (11) can be a non-metallic skateboard or a metallic skateboard.

6. The seismic isolation bearing according to claim 1, characterized in that, The upper seat plate (1) and the middle seat plate (4) are provided with a spherical friction pair that can rotate relative to each other. The spherical friction pair includes a spherical non-metallic sliding plate (2) provided on the lower surface of the upper seat plate (1) and a spherical stainless steel sliding plate (3) provided on the upper surface of the middle seat plate (4).

7. The seismic isolation bearing according to claim 1, characterized in that, The middle seat plate (4) and the convex ramp seat plate (10) are provided with a planar friction pair that can slide relative to each other. The planar friction pair includes a planar non-metallic sliding plate (5) provided on the lower surface of the middle seat plate (4) and a planar stainless steel sliding plate (6) provided on the upper surface of the convex ramp seat plate (10).

8. The seismic isolation bearing according to claim 1, characterized in that, A permanent baffle (101) is provided above the convex ramp seat plate (10) along its circumference, and a vertical guide friction pair that can slide relative to the permanent baffle (101) and the upper seat plate (1) is provided.

9. The seismic isolation bearing according to claim 8, characterized in that, The vertical guide friction pair includes a guide non-metallic slide plate (8) located on the outside of the upper seat plate (1) and a guide stainless steel slide plate (9) located on the inside of the permanent baffle (101).

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