Variable-damping friction pendulum seismic mitigation and isolation support and method

Abstract

The support comprises an upper seat plate, a spherical crown lining plate, a middle steel lining plate and a lower seat plate, the upper seat plate is fixedly installed at the bottom of a beam bottom, the spherical crown lining plate is arranged between the upper seat plate and the middle steel lining plate, the middle steel lining plate is arranged between the spherical crown lining plate and the lower seat plate, and the spherical crown lining plate is fixedly installed on the lower seat plate. The lower seat plate is fixedly mounted at the top of a bridge pier, the bottom surface of the upper seat plate is fixedly connected with a first limiting ring through a first anti-shear pin, the first limiting ring abuts against the middle steel lining plate, the top surface of the lower seat plate is fixedly connected with a second limiting ring through a second anti-shear pin, and the second limiting ring abuts against the middle steel lining plate. In a normal use state, the slip surface adopts a large curvature radius and a small friction coefficient to provide smaller damping, reduce the acting force of the support on a bridge and reduce the lifting of a beam end, and in an earthquake state, the slip surface adopts a small curvature radius and a large friction coefficient to provide larger damping, so that the shock absorption and isolation effect of the support is improved; and displacement of the bridge under the earthquake condition is controlled.

Description

Technical Field

[0001] The present invention belongs to the technical field of vibration reduction and isolation, and more specifically, relates to a variable damping friction pendulum vibration reduction and isolation support and method. Background Art

[0002] In the field of contemporary civil engineering, earthquake disasters pose a serious threat to the safety of bridges and building structures, and the development of seismic isolation technology provides a key solution for improving the seismic performance of structures. Among them, the friction pendulum seismic isolation bearing has become an indispensable core component in bridge and construction engineering due to its excellent self-reset ability and excellent seismic isolation performance. It cleverly uses the principle of a simple pendulum to reduce the input of seismic energy into the structure from the source by extending the natural vibration period of the structure. At the same time, during the movement of the bearing, with the help of continuous kinetic potential energy conversion and reciprocating friction energy dissipation mechanism, it can efficiently dissipate seismic energy and significantly reduce the degree of damage to the structure caused by earthquakes.

[0003] However, with the deepening of engineering practice and the increasing complexity of earthquake scenarios, the limitations of traditional friction pendulum bearings have gradually become apparent. When responding to earthquakes of varying intensities, the fixed nature of their stiffness and damping characteristics has become a major shortcoming. Frequent earthquakes occur frequently, and at this time, the bearings need to have moderate stiffness and damping to effectively control structural vibrations and prevent small vibrations from causing cumulative damage to the structure. Rare earthquakes are extremely intense, requiring the bearings to provide greater deformation capacity and stronger energy dissipation capacity to prevent the structure from collapsing due to severe vibrations. However, traditional friction pendulum bearings cannot flexibly adjust their own characteristics according to the intensity of the earthquake. In frequent earthquakes, the excessive stiffness may lead to poor shock absorption effects. In rare earthquakes, insufficient damping may make it difficult to fully dissipate energy, and the ideal seismic isolation state can never be achieved. For complex engineering structures such as long-span bridges, traditional friction pendulum bearings face even more severe challenges. Long-span bridges have large spans and complex structures, and the performance requirements for the bearings are more stringent. When a larger seismic isolation radius is used, although the shock absorption effect can be improved to a certain extent, it will cause a significant amount of lifting at the beam end. This not only destroys the smoothness of the bridge, causing obvious ups and downs on the bridge deck, seriously affecting driving comfort, but may even pose a potential threat to vehicle driving safety; if a smaller seismic isolation radius is selected, the bearing stiffness will be smaller, the shock absorption effect will be greatly reduced, and it will be difficult to effectively control the displacement of the bridge in the event of an earthquake. Once a strong earthquake occurs, excessive displacement may lead to serious consequences such as beam collision and bearing damage, endangering the overall safety of the bridge. Summary of the Invention

[0004] In response to the above defects or improvement needs of the prior art, the present invention provides a variable damping friction pendulum isolation bearing and method. Under normal working conditions, the bearing mainly relies on the first rotating friction pair and the second rotating friction pair to work together to achieve flexible sliding in the longitudinal or lateral direction. At this time, the third rotating friction pair remains stationary, and the first rotating friction pair adopts a smaller friction coefficient, so that the bearing can significantly reduce the additional force generated by sliding during the sliding process, ensuring its long-term safe and stable operation. At the same time, the first equivalent isolation formed by the first rotating friction pair and the second rotating friction pair is large, so that when the bridge is in normal use, it effectively reduces the amount of lifting of the beam end under normal use, greatly improves the smoothness of the road surface, creates a smooth driving environment for vehicles, and significantly improves driving comfort and safety; when encountering working conditions such as earthquakes, the first rotating friction pair and the second rotating friction pair, with their smaller friction coefficient and larger first equivalent isolation radius, give priority to starting and coordinating rotation and sliding, so as to disperse and consume seismic energy. As the seismic force continues to act, when the bearing slides When it reaches the normal displacement limit position, that is, when a limit is formed between the lower seat plate and the middle steel lining plate, the second rotating friction pair and the third rotating friction pair begin to work in relay cooperation. The third rotating friction pair adopts a larger friction coefficient, and the second equivalent seismic isolation radius formed by the second rotating friction pair and the third rotating friction pair is smaller, which can produce greater stiffness and damping, and improve the horizontal damping performance of the support, so that it can effectively absorb and dissipate seismic energy during an earthquake, accurately control the displacement of the bridge, avoid damage to the bridge structure due to excessive displacement, and provide reliable safety protection for the bridge in earthquake disasters.

[0005] In order to achieve the above-mentioned object, according to the first aspect of the present invention, a variable damping friction pendulum seismic isolation support is provided, comprising an upper seat plate, a spherical cap lining plate, an intermediate steel lining plate and a lower seat plate; wherein, The upper seat plate is fixedly installed on the bottom of the beam, the spherical cap lining plate is arranged between the upper seat plate and the middle steel lining plate, the middle steel lining plate is arranged between the spherical cap lining plate and the lower seat plate, and the lower seat plate is fixedly installed on the top of the pier; The bottom surface of the upper seat plate is fixedly connected to a first limiting ring via a first shear pin, and the first limiting ring abuts against the middle steel liner. The top surface of the lower seat plate is fixedly connected to a second limiting ring via a second shear pin, and the second limiting ring abuts against the middle steel liner. When the earthquake force is greater than the shear force of the first shear pin and the second shear pin, the first shear pin and the second shear pin are sheared off, and the lower seat plate can limit the middle steel lining plate, and the upper seat plate can limit the spherical crown lining plate to prevent the support from moving beyond the limit, thereby avoiding the upper structure from falling off and structural damage to the upper structure due to excessive lateral load, thereby effectively ensuring the structural safety of the upper structure.

[0006] Furthermore, the lower seat plate is rectangular, the upper surface of which is a concave spherical surface, and a spherical stainless steel mirror is fixedly installed on the upper surface. The lower surface of the intermediate steel lining plate is provided with a convex spherical surface matching the concave spherical surface of the lower seat plate, and a third spherical slide plate is inlaid on its lower surface. The spherical stainless steel mirror on the upper surface of the lower seat plate and the third spherical slide plate inlaid on the lower surface of the intermediate steel lining plate cooperate with each other to form a first rotating friction pair.

[0007] Furthermore, the upper surface of the intermediate steel liner is a concave spherical surface, and a second spherical slide plate is inlaid on its upper surface. The lower surface of the spherical crown liner is provided with a convex spherical surface that matches the concave spherical surface of the lower surface of the intermediate steel liner, and a spherical stainless steel mirror is fixedly installed on its lower surface. The second spherical slide plate on the upper surface of the intermediate steel liner cooperates with the convex spherical surface of the spherical crown liner to form a second rotating friction pair.

[0008] Furthermore, the upper seat plate is rectangular, and its lower surface is a concave spherical surface, and a spherical stainless steel mirror is fixedly installed on the lower surface. The upper surface of the spherical crown lining plate is provided with a convex spherical surface matching the concave spherical surface of the upper seat plate, and its upper surface is inlaid with a first spherical slide plate. The spherical stainless steel mirror on the lower surface of the upper seat plate and the first spherical slide plate inlaid on the upper surface of the spherical crown lining plate cooperate with each other to form a third rotating friction pair.

[0009] Furthermore, a first annular boss is provided at the bottom of the upper seat plate, and a plurality of first pin holes are provided at intervals at the bottom of the first annular boss. The first limiting ring is a circular structure with a first through hole in the middle. The first through hole is circular, and a second pin hole is provided on the outer ring of the first limiting ring corresponding to the position of the first pin hole. The two are connected by a first shear pin to realize a fixed connection between the first limiting ring and the upper seat plate.

[0010] Furthermore, when the support is a fixed support, a second annular boss is provided on the top of the lower seat plate, a plurality of fourth pin holes are provided at intervals on the top of the second annular boss, the second limiting ring is a circular structure with a second through hole in the middle, the second through hole is circular, and a third pin hole is provided on the outer ring of the second limiting ring corresponding to the position of the fourth pin hole, and the two are connected through a second shear pin to achieve a fixed connection between the second limiting ring and the lower seat plate; Furthermore, when the support is a fixed type support, the intermediate steel lining is a cylinder, and its top outer wall is provided with a circular first limiting protrusion, whose size is adapted to the first through hole, and the outer surface of the first limiting protrusion is an arc surface, and the middle outer wall of the intermediate steel lining is provided with a circular second limiting protrusion, which abuts and cooperates with the second through hole of the second limiting ring.

[0011] Furthermore, when the support is a movable support, the second limiting ring is a circular structure with a second through hole in the middle, the second through hole is polygonal, and the arc chamfers between adjacent side walls are formed, and a pair of opposite inner side walls are provided with a stainless steel plate; Furthermore, when the support is a movable support, a polygonal second limiting protrusion is provided on the outer wall of the middle part of the intermediate steel lining plate, the size of which is adapted to the second through hole, and two adjacent side walls of the polygonal second limiting protrusion are provided with arc chamfers, wherein the two opposite side walls are fixedly installed with sliding strips, and a sliding friction pair is formed between the sliding strip and the stainless steel plate on the second limiting ring.

[0012] Furthermore, the friction coefficient between the first spherical slide and the stainless steel mirror is 0.05-0.08, the friction coefficient between the second spherical slide and the stainless steel mirror is not greater than 0.03, and the friction coefficient between the third spherical slide and the stainless steel mirror is not greater than 0.03.

[0013] Furthermore, the first spherical skateboard and the third spherical skateboard are made of ultra-wear-resistant polymer skateboard material, forming a friction pair with the stainless steel mirror. Under the test conditions of no silicone grease lubrication, the cumulative linear wear rate of 50km of reciprocating sliding is less than 10μm / km, the ultimate compressive strength is ≥200MPa, the allowable compressive stress is ≥50MPa, and there is no damage under the rapid shearing action of 500mm / s.

[0014] Furthermore, different shear forces are set for the first shear pin and the second shear pin, wherein the second shear pin is preferentially sheared under the action of E1 earthquake, while the first shear pin remains intact; under the action of E2 earthquake, both the first shear pin and the second shear pin are sheared, thereby achieving graded energy dissipation and displacement control.

[0015] According to another aspect of an embodiment of the present invention, a variable damping friction pendulum vibration isolation method is provided, comprising: S100: Under normal operating conditions, the bearing mainly relies on the first and second rotating friction pairs to work together to achieve flexible longitudinal or lateral sliding. At this time, the third rotating friction pair remains stationary. The first rotating friction pair uses a smaller friction coefficient, which allows the bearing to significantly reduce the additional force generated by sliding during the sliding process, ensuring its long-term safe and stable operation. At the same time, the first equivalent seismic isolation radius formed by the first and second rotating friction pairs is large, which effectively reduces the amount of lift at the beam end during normal use of the bridge, greatly improving the smoothness of the road surface. S200: When encountering working conditions such as earthquakes, the first rotating friction pair and the second rotating friction pair are activated first and coordinately rotated and slipped by virtue of their smaller friction coefficient and larger first equivalent seismic isolation radius, thereby dispersing and consuming earthquake energy; S300: As the earthquake force continues to act, when the bearing slides to the limit position of normal displacement, that is, a limit is formed between the lower seat plate and the middle steel lining plate, the second rotating friction pair and the third rotating friction pair begin to work in relay cooperation. The third rotating friction pair adopts a larger friction coefficient, and the second equivalent seismic isolation radius formed by the second rotating friction pair and the third rotating friction pair is smaller, which can generate a larger horizontal damping force, thereby improving the horizontal damping performance of the bearing, enabling it to effectively absorb and dissipate seismic energy during an earthquake, control the displacement of the bridge, avoid damage to the bridge structure due to excessive displacement, and provide reliable safety protection for the bridge in earthquake disasters.

[0016] In general, the above technical solutions conceived by the present invention can achieve the following beneficial effects compared with the prior art: 1. The variable damping friction pendulum seismic isolation bearing of the present invention, under normal working conditions, the bearing mainly relies on the coordinated work of the first rotating friction pair and the second rotating friction pair to achieve flexible sliding in the longitudinal or lateral direction. At this time, the third rotating friction pair remains stationary, and the first rotating friction pair adopts a smaller friction coefficient, so that the bearing can greatly reduce the additional force generated by sliding during the sliding process, thereby ensuring its long-term safe and stable operation; at the same time, the first equivalent seismic isolation radius formed by the first rotating friction pair and the second rotating friction pair is large, so that when the bridge is in normal use, the lifting amount of the beam end under normal use is effectively reduced, which greatly improves the smoothness of the road surface, creates a smooth driving environment for vehicles, and significantly improves driving comfort and safety.

[0017] 2. A variable damping friction pendulum seismic isolation bearing of the present invention, when encountering working conditions such as earthquakes, the first rotating friction pair and the second rotating friction pair, with their smaller friction coefficient and larger first equivalent seismic isolation radius, are preferentially started and coordinated to rotate and slide, thereby dissipating and consuming seismic energy; as the seismic force continues to act, when the bearing slides to the limit position of normal displacement, that is, after a limit is formed between the lower seat plate and the middle steel lining plate, the second rotating friction pair and the third rotating friction pair begin to relay and work together, the third rotating friction pair adopts a larger friction coefficient, and the second equivalent seismic isolation radius formed by the second rotating friction pair and the third rotating friction pair is smaller, which can generate a larger horizontal damping force, thereby improving the horizontal damping performance of the bearing, enabling it to effectively absorb and dissipate seismic energy in an earthquake, accurately control the displacement of the bridge, avoid damage to the bridge structure due to excessive displacement, and provide reliable safety protection for the bridge in earthquake disasters.

[0018] 3. The variable damping friction pendulum seismic isolation bearing of the present invention realizes the precise combination and matching of the friction coefficient and the equivalent seismic isolation radius by setting differentiated friction coefficients for the first rotating friction pair and the third rotating friction pair, and setting different curvature radii for the first equivalent seismic isolation radius and the second equivalent seismic isolation radius. It can present lower stiffness and damping when the bridge is in normal operation, ensuring the flexibility of structural movement; when an earthquake occurs, it can quickly adjust to higher stiffness and damping to enhance the stability and seismic resistance of the structure, thereby fully adapting to the stiffness and damping requirements of the bridge under different working conditions, and providing reliable protection for the safety of the bridge structure.

[0019] 4. A variable damping friction pendulum seismic isolation bearing of the present invention has a plurality of first pin holes and fourth pin holes uniformly distributed on the circumference of the upper seat plate and the lower seat plate, and a third pin hole and a fourth pin hole uniformly distributed on the surface of the first limit ring and the second limit ring respectively. During the actual assembly process, the first shear pin and the second pin hole successively penetrate the pin holes corresponding to the upper seat plate and the first limit ring, and the lower seat plate and the second limit ring, thereby firmly connecting them into an integral structure. When the load reaches the preset shear force threshold, the shear pins will be sheared at the same time, so that the bearings can start the swing mechanism at the same time, and the bridge bearings can work together to avoid premature failure due to uneven force on individual bearings, thereby giving full play to the shock-absorbing and energy-consuming role of each bearing, significantly improving the overall energy consumption capacity of the bridge, effectively reducing the degree of damage to the bridge structure caused by earthquakes, providing reliable safety protection for the bridge in earthquake disasters, and ensuring the integrity and stability of the bridge structure.

[0020] 5. The variable damping friction pendulum seismic isolation bearing of the present invention has a second annular boss on the lower seat plate that can limit the middle steel lining plate when the bearing displacement exceeds the design displacement, and the first annular boss on the upper seat plate can limit the spherical crown lining plate to prevent the bearing displacement from exceeding the limit, thereby avoiding the upper structure from falling off and structural damage to the upper structure caused by excessive lateral load, thereby effectively ensuring the structural safety of the upper structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the overall structure of a variable damping friction pendulum seismic isolation support according to an embodiment of the present invention; Figure 2 This is an elevational view of an upper base plate of a variable damping friction pendulum seismic isolation support according to an embodiment of the present invention; Figure 3 A bottom view of an upper base plate of a variable damping friction pendulum seismic isolation support according to an embodiment of the present invention; Figure 4 This is an elevational view of a first limiting ring of a variable damping friction pendulum isolation support according to an embodiment of the present invention; Figure 5A top view of a first limiting ring of a variable damping friction pendulum seismic isolation support according to an embodiment of the present invention; Figure 6 This is an elevational view of a second limiting ring of a variable damping friction pendulum isolation support according to an embodiment of the present invention; Figure 7 A top view of a second limiting ring of a variable damping friction pendulum seismic isolation support according to an embodiment of the present invention; Figure 8 This is an elevation view of the middle steel lining plate of a variable damping friction pendulum seismic isolation support according to an embodiment of the present invention; Figure 9 A top view of the middle steel lining plate of a variable damping friction pendulum seismic isolation support according to an embodiment of the present invention; Figure 10 This is an elevational view of a lower base plate of a variable damping friction pendulum seismic isolation support according to an embodiment of the present invention; Figure 11 This is a top view of a lower base plate of a variable damping friction pendulum seismic isolation support according to an embodiment of the present invention; Figure 12 This is an elevational view of a middle steel lining plate of a variable damping friction pendulum seismic isolation support according to another embodiment of the present invention; Figure 13 A top view of the middle steel lining plate of a variable damping friction pendulum seismic isolation support according to an embodiment of the present invention; Figure 14 This is an elevational view of a second limiting ring of a variable damping friction pendulum isolation support according to an embodiment of the present invention; Figure 15 The figure is a top view of the second limiting ring of a variable damping friction pendulum seismic isolation support according to an embodiment of the present invention.

[0022] In all the drawings, the same figure marks represent the same technical features, specifically: 1-upper seat plate, 101-first pin hole, 102-first circular boss, 2-first spherical slide plate, 3-spherical crown lining plate, 4-first shear pin, 5-first limiting ring, 51-second pin hole, 52-first through hole, 6-second spherical slide plate, 7-middle steel lining plate, 71-first limiting protrusion, 72-second limiting protrusion, 73-slide bar, 8-third spherical slide plate, 9-second limiting ring, 91-third pin hole, 92-second through hole, 93-stainless steel plate, 10-second shear pin, 11-lower seat plate, 1101-fourth pin hole, 1102-second circular boss. DETAILED DESCRIPTION

[0023] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only intended to illustrate the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0024] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0025] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features specified as "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that ordinary technicians in this field can implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0026] In this patent, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises..." does not preclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0027] Example 1 like Figures 1-11As shown, according to the first aspect of the present invention, a variable damping friction pendulum seismic isolation bearing is provided, comprising an upper seat plate 1, a spherical crown lining plate 3, an intermediate steel lining plate 7 and a lower seat plate 11, wherein the upper seat plate 1 is fixedly installed at the bottom of the beam bottom to ensure that the bearing is tightly combined with the beam bottom so that the force exerted on the main beam can be smoothly transmitted to the bearing structure, the spherical crown lining plate 3 is arranged between the upper seat plate 1 and the intermediate steel lining plate 7, the intermediate steel lining plate 7 is arranged between the spherical crown lining plate 3 and the lower seat plate 11, and the lower seat plate 11 is fixedly installed on the top of the bridge pier. The bearing structure of the present invention is composed of the upper seat plate 1, the spherical crown lining plate 3, the intermediate steel lining plate 7 and the lower seat plate 11, wherein the upper seat plate is fixed to the bottom of the beam bottom and the lower seat plate is fixed to the top of the bridge pier, forming a complete force transmission path, which can evenly transfer the vertical load and horizontal force exerted on the main beam to the lower foundation. The curved surface design of the spherical crown lining enables it to form spherical contact with the upper seat plate and the middle steel lining plate, allowing the support to produce rotational deformation to adapt to the deflection of the beam and other conditions, thereby reducing the additional internal force of the beam. In addition, the support adopts a modular design, and each component can be independently processed and assembled, which is convenient for installation and debugging.

[0028] Furthermore, the lower seat plate 11 is rectangular, and a plurality of connection holes are provided at its bottom, which are mainly used for a firm connection with the bridge pier. The lower seat plate 11 can be reliably fixed to the bridge pier through bolts and other connectors, thereby providing a stable support foundation for the entire structure; the upper surface of the lower seat plate 11 is a concave spherical surface, and a spherical stainless steel mirror is fixedly installed on its upper surface. The spherical stainless steel mirror has the characteristics of high hardness and low friction coefficient, which can effectively reduce friction loss and improve the rotation flexibility of the structure; the lower surface of the intermediate steel liner is provided with a convex spherical surface matching the concave spherical surface of the lower seat plate 11, so that the two can achieve relative rotation, and The lower surface of the middle steel lining plate 7 is inlaid with a third spherical slide plate 8. The spherical stainless steel mirror surface on the upper surface of the lower seat plate 11 cooperates with the third spherical slide plate 8 inlaid on the lower surface of the middle steel lining plate 7 to form a first rotating friction pair, so that the middle steel lining plate 7 and the lower seat plate 11 can rotate relatively flexibly, thereby realizing the multi-directional free rotation of the beam body, effectively adapting to the displacement caused by temperature and load changes, and greatly improving the rotation flexibility of the beam body. The spherical stainless steel mirror surface and the third spherical slide plate 8 greatly reduce the resistance of the beam body during rotation, and both small angle adjustments and large-scale rotations can be achieved smoothly.

[0029] Furthermore, the upper surface of the intermediate steel liner 7 is a concave spherical surface, inlaid with a second spherical slide 6. The lower surface of the spherical crown liner 3 is provided with a convex spherical surface that matches the concave spherical surface of the lower surface of the intermediate steel liner 7. A spherical stainless steel mirror is fixedly mounted on the lower surface of the spherical crown liner 3. The second spherical slide 6 on the upper surface of the intermediate steel liner 7 cooperates with the convex spherical surface of the spherical crown liner 3 to form a second rotating friction pair, allowing relatively flexible rotation between the intermediate steel liner 7 and the spherical crown liner 3, thereby achieving multi-directional free rotation of the beam and effectively adapting to displacement caused by temperature and load changes. The convex spherical surface of the spherical crown liner 3 and the second spherical slide 6 significantly reduce the resistance of the beam during rotation, allowing both small angle adjustments and large-scale rotations to be achieved smoothly and smoothly. The second rotating friction pair and the first rotating friction pair together form a coordinated rotating surface, which rotates in conjunction with each other in the normal state of the support to achieve longitudinal or lateral sliding functions.

[0030] Furthermore, the upper seat plate 1 is rectangular, and a connecting hole is provided on the top thereof for connecting to the bottom of the beam. The lower surface of the upper seat plate 1 is a concave spherical surface, and a spherical stainless steel mirror is fixedly installed on the lower surface. The upper surface of the spherical crown lining plate 3 is provided with a convex spherical surface matching the concave spherical surface of the upper seat plate 1, and the upper surface of the spherical crown lining plate 3 is inlaid with a first spherical skateboard 2. The spherical stainless steel mirror on the lower surface of the upper seat plate 1 and the first spherical skateboard 2 inlaid on the upper surface of the spherical crown lining plate 3 cooperate with each other to form a third rotating friction pair, thereby realizing multi-directional free rotation of the beam body and effectively adapting to the displacement caused by temperature and load changes. The spherical stainless steel mirror and the first spherical skateboard 2 greatly reduce the resistance of the beam body during rotation, and both small angle adjustments and large-scale rotations can be achieved smoothly and smoothly; the third rotating friction pair and the second rotating friction pair together constitute a coordinated rotating surface, which rotates synergistically under an earthquake state to realize the sliding energy dissipation function.

[0031] Furthermore, a first limiting ring 5 is fixedly connected to the bottom surface of the upper seat plate 1 through a first shear pin 4 , and the first limiting ring 5 abuts against the middle steel liner 7 .

[0032] Specifically, the bottom of the upper seat plate 1 is provided with a first annular boss 102, and the bottom of the first annular boss 102 is provided with a plurality of first pin holes 101 at intervals. The first limiting ring 5 is a circular structure with a first through hole 52 in the middle. The first through hole 52 is circular and is used to limit the relative displacement between the upper seat plate 1 and the intermediate steel liner 7, ensuring that the upper seat plate 1 and the spherical cap liner 3 do not slip under normal operating conditions and reliably transmit horizontal loads. The outer ring of the first limiting ring 5 is provided with a second pin hole 51 corresponding to the position of the first pin hole 101. The two are connected by a first shear pin 4 to achieve a fixed connection with the upper seat plate 1. At the same time, when the seismic force is greater than the shear force of the first shear pin 4, causing the first shear pin 4 to be sheared, the first annular boss 102 of the upper seat plate 1 can limit the spherical cap liner 3, preventing the support from exceeding the displacement limit, thus preventing the beam from falling off, and also preventing the beam from being damaged due to excessive lateral load, thereby effectively ensuring the structural safety of the beam.

[0033] Furthermore, the top surface of the lower seat plate 11 is fixedly connected to a second limiting ring 9 via a second shear pin 10 , and the second limiting ring 9 abuts against the middle steel liner 7 .

[0034] Specifically, when the support is a fixed support, a second annular boss 1102 is provided on the top of the lower seat plate 11, and a number of fourth pin holes 1101 are provided at intervals on the top of the second annular boss 1102. The second limiting ring 9 is a circular structure with a second through hole 92 in the middle. The second through hole 92 is circular and is used to limit the relative displacement of the lower seat plate 11 and the middle steel lining plate 7 to ensure that there is no slippage between the lower seat plate 11 and the middle steel lining plate 7 under normal working conditions and to reliably transmit horizontal loads. A third pin hole 91 is provided on the outer ring of the second limiting ring 9 corresponding to the position of the fourth pin hole 1101, and the two are connected through the second shear pin 10 to achieve a fixed connection with the lower seat plate 11. At the same time, when the seismic force is greater than the shear force of the second shear pin 10, the second shear pin 10 is sheared, and the second annular boss 1102 of the lower seat plate 11 can limit the middle steel lining plate 7 to prevent the support from moving beyond the limit, thereby avoiding the beam from falling off and avoiding structural damage to the beam due to excessive lateral load, thereby effectively ensuring the structural safety of the beam.

[0035] Furthermore, the intermediate steel lining plate 7 is a cylinder, and a circular first limiting protrusion 71 is provided on the outer side wall of its top, and its size is adapted to the first through hole 52. The outer surface of the first limiting protrusion 71 is an arc surface. When the support undergoes horizontal displacement, the arc surface of the first limiting protrusion 71 forms a sliding contact with the inner wall of the first through hole 52 of the first limiting ring 5, allowing flexible relative rotation between the intermediate steel lining plate 7 and the first limiting ring 5, thereby adapting to the multi-directional displacement requirements of the structure under the action of earthquake or temperature, while maintaining the reliability of the limiting function.

[0036] Furthermore, a circular second limiting protrusion 72 is provided on the outer wall of the middle part of the intermediate steel liner 7, which abuts and cooperates with the second through hole 92 of the second limiting ring 9 to limit the relative displacement of the lower seat plate 11 and the intermediate steel liner 7, ensuring that the lower seat plate 11 and the intermediate steel liner 7 do not slip under normal working conditions and reliably transmit horizontal loads.

[0037] Specifically, under normal working conditions, the support can slide flexibly in the longitudinal or transverse direction, mainly relying on the coordinated rotation of the first rotating friction pair and the second rotating friction pair, while the third rotating friction pair remains stationary. Among them, the first rotating friction pair and the second rotating friction pair adopt a smaller friction coefficient, which can greatly reduce the additional force generated by sliding during the sliding of the support, and present a lower stiffness and damping when the bridge is in normal operation, ensuring the flexibility of structural movement, thereby providing reliable protection for the bridge structure and ensuring its long-term safe and stable operation. In addition, the first equivalent seismic isolation radius formed by the first rotating friction pair and the second rotating friction pair is large, which reduces the lifting amount of the beam end of the bridge under normal use. The reduction in the lifting amount of the beam end effectively improves the smoothness of the road surface, avoids bumps, ups and downs, and creates a smooth road environment for vehicle driving, greatly improving driving comfort and safety.

[0038] Furthermore, the first spherical skateboard 2 and the third spherical skateboard 8 are made of super-wear-resistant polymer skateboard material, forming a friction pair with the stainless steel mirror. Under the test conditions without silicone grease lubrication, the cumulative linear wear rate of 50km of reciprocating sliding is less than 10μm / km, the ultimate compressive strength is ≥200MPa, the allowable compressive stress is ≥50MPa, and there is no damage under the rapid shearing action of 500mm / s.

[0039] Furthermore, the friction coefficient between the first spherical skateboard 2 and the stainless steel mirror is 0.05-0.08, the friction coefficient between the second spherical skateboard 6 and the stainless steel mirror is not greater than 0.03, and the friction coefficient between the third spherical skateboard 8 and the stainless steel mirror is not greater than 0.03.

[0040] Furthermore, different shear forces are set for the first shear pin 4 and the second shear pin 10, wherein the second shear pin 10 is preferentially sheared under the action of E1 earthquake, while the first shear pin 4 remains intact; under the action of E2 earthquake, both the first shear pin 4 and the second shear pin 10 are sheared, realizing graded energy dissipation and displacement control.

[0041] Specifically, a multi-level seismic protection system is constructed by designing differentiated shear forces for the first shear pins 4 and the second shear pins 10. The shear force of the second shear pins 10 is set at a relatively low level, which only meets the bearing requirements of horizontal loads during normal operation of the bridge. When the E1 earthquake occurs, with the action of the seismic force, the second shear pins 10 are the first to bear the load exceeding the set value, and then shear. At this time, the first shear pins 4 remain intact, providing basic support for the structure. At the same time, the middle steel lining plate 7 gains freedom due to the shearing of the second shear pins 10, and can slide freely in all directions along the lower seat plate 11. This sliding process consumes seismic energy through friction, effectively buffering the impact of the earthquake on the bridge structure.

[0042] When encountering a stronger E2 earthquake, since the first equivalent isolation radius is larger and the first and second rotating friction pairs use a low friction coefficient, at the initial stage of the earthquake force, the two rotating friction pairs will prioritize coordinated rotation and sliding to disperse the earthquake energy. As the earthquake force continues to act, when the sliding reaches the limit position of normal displacement, the second annular boss 1102 of the lower seat plate 11 can limit the middle steel liner 7 and constrain the relative displacement of the two. At this time, the first shear pin 4 is cut off, and the second and third rotating friction pairs begin to rotate and slide in coordination. The third rotating friction pair uses a higher friction coefficient, which can consume a large amount of earthquake energy during the rotation process and significantly improve the overall energy consumption capacity of the support. At the same time, the second equivalent isolation radius formed by the second and third rotating friction pairs is smaller, which can generate greater stiffness and damping, control the displacement of the bridge in the earthquake, avoid damage to the bridge structure due to excessive displacement, and provide all-round, multi-level seismic protection for the bridge.

[0043] When the support displacement exceeds the designed displacement, the second annular boss 1102 of the lower seat plate 11 can limit the middle steel lining plate 7, and the first annular boss 102 of the upper seat plate 1 can limit the spherical crown lining plate 3 to prevent the support displacement from exceeding the limit, thereby avoiding the beam from falling off and structural damage caused by excessive lateral load, thereby damaging the beam and effectively ensuring the structural safety of the beam.

[0044] Furthermore, the middle parts of the first shear pin 4 and the second shear pin 10 are both provided with shear grooves, and the size of the shear grooves is determined according to the measured shear strength of the alloy steel material; the alloy steels are produced by the same manufacturer, the same batch, and the same process, and the shear strength is sampled and tested after batch purchase. The test results are statistically averaged and the average value is taken. The average value of the test shear strength is used to correct the diameter of the shear pin intermittent groove, thereby improving the matching accuracy between the actual shear force and the designed shear force, thereby realizing accurate graded energy consumption control under earthquake action.

[0045] Example 2 like Figure 12-15As shown, an embodiment of the present invention provides another variable damping friction pendulum seismic isolation bearing. In this embodiment, other contents are the same as those in Example 1, and the only difference from Example 1 is that, when the bearing is a movable bearing, the second limiting ring 9 is a circular structure with a second through hole 92 in the middle. The second through hole 92 is polygonal, with arc chamfers between adjacent side walls, and a pair of opposite inner side walls are provided with stainless steel plates 93, so that the middle steel lining plate 7 slides longitudinally or transversely in the second through hole 92, allowing the middle steel lining plate 7 to move within the normal temperature displacement range. When the normal temperature displacement range is exceeded under earthquake conditions, the middle steel lining plate 7 is limited and the horizontal force is transmitted.

[0046] Furthermore, a polygonal second limiting protrusion 72 is provided on the outer wall of the middle part of the intermediate steel lining plate 7, the size of which is adapted to the second through hole 92, and the two adjacent side walls of the polygonal second limiting protrusion 72 are provided with arc chamfers, wherein the two opposite side walls are fixedly installed with a sliding bar 73, and a sliding friction pair is formed between the sliding bar 73 and the stainless steel plate 93 on the second limiting ring 9 to reduce the sliding friction coefficient, realize the limiting and guiding of the support, and transmit the horizontal force of the support.

[0047] Example 3 According to a second aspect of the present invention, a variable damping friction pendulum vibration isolation method is provided, comprising: S100: Under normal operating conditions, the bearing mainly relies on the first and second rotating friction pairs to work together to achieve flexible longitudinal or lateral sliding. At this time, the third rotating friction pair remains stationary. The first rotating friction pair uses a smaller friction coefficient, which allows the bearing to significantly reduce the additional force generated by sliding during the sliding process, ensuring its long-term safe and stable operation. At the same time, the first equivalent seismic isolation radius formed by the first and second rotating friction pairs is large, which effectively reduces the amount of lift at the beam end during normal use of the bridge, greatly improving the smoothness of the road surface. S200: When encountering working conditions such as earthquakes, the first rotating friction pair and the second rotating friction pair are activated first and coordinately rotated and slipped by virtue of their smaller friction coefficient and larger first equivalent seismic isolation radius, thereby dispersing and consuming earthquake energy; S300: As the earthquake force continues to act, when the bearing slides to the limit position of normal displacement, that is, a limit is formed between the lower seat plate 11 and the middle steel lining plate 7, the second rotating friction pair and the third rotating friction pair begin to work in relay cooperation. The third rotating friction pair adopts a larger friction coefficient, and the second equivalent seismic isolation radius formed by the second rotating friction pair and the third rotating friction pair is smaller, which can generate a larger horizontal damping force, thereby improving the horizontal damping performance of the bearing, enabling it to effectively absorb and dissipate seismic energy during an earthquake, accurately control the displacement of the bridge, avoid damage to the bridge structure due to excessive displacement, and provide reliable safety protection for the bridge in earthquake disasters.

[0048] It will be easily understood by those skilled in the art that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions 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 variable damping friction pendulum seismic isolation support, characterized in that: It comprises an upper seat plate (1), a spherical crown lining plate (3), an intermediate steel lining plate (7) and a lower seat plate (11); wherein, The upper seat plate (1) is fixedly mounted on the bottom of the beam, the spherical cap lining plate (3) is arranged between the upper seat plate (1) and the middle steel lining plate (7), the middle steel lining plate (7) is arranged between the spherical cap lining plate (3) and the lower seat plate (11), and the lower seat plate (11) is fixedly mounted on the top of the pier; The bottom surface of the upper seat plate (1) is fixedly connected to a first limiting ring (5) via a first anti-shear pin (4), and the first limiting ring (5) abuts against the middle steel lining plate (7); the top surface of the lower seat plate (11) is fixedly connected to a second limiting ring (9) via a second anti-shear pin (10), and the second limiting ring (9) abuts against the middle steel lining plate (7); When the earthquake force is greater than the shearing force of the first shear pin (4) and the second shear pin (9), the first shear pin (4) and the second shear pin (9) are sheared, and the lower seat plate (11) can limit the position of the middle steel lining plate (7), and the upper seat plate (1) can limit the position of the spherical crown lining plate (3), thereby preventing the support from moving beyond the limit, thus preventing the beam from falling off, and also preventing the beam from being damaged due to excessive lateral load, thereby effectively ensuring the structural safety of the beam.

2. The variable damping friction pendulum seismic isolation support according to claim 1, characterized in that: The lower seat plate (11) is rectangular, and its upper surface is a concave spherical surface, and a spherical stainless steel mirror is fixedly installed on the upper surface. The lower surface of the intermediate steel lining plate (7) is provided with a convex spherical surface matching the concave spherical surface of the lower seat plate (11), and its lower surface is inlaid with a third spherical slide plate (8). The spherical stainless steel mirror on the upper surface of the lower seat plate (11) and the third spherical slide plate (8) inlaid on the lower surface of the intermediate steel lining plate (7) cooperate with each other to form a first rotating friction pair.

3. The variable damping friction pendulum seismic isolation support according to claim 1, characterized in that: The upper surface of the intermediate steel liner (7) is a concave spherical surface, and a second spherical slide plate (6) is embedded in the upper surface of the intermediate steel liner (7). The lower surface of the spherical crown liner (3) is provided with a convex spherical surface that matches the concave spherical surface of the lower surface of the intermediate steel liner (7). The second spherical slide plate (6) on the upper surface of the intermediate steel liner (7) and the convex spherical surface of the spherical crown liner (3) cooperate with each other to form a second rotational friction pair.

4. The variable damping friction pendulum seismic isolation support according to claim 1, characterized in that: The upper seat plate (1) is rectangular, and its lower surface is a concave spherical surface, and a spherical stainless steel mirror is fixedly installed on the lower surface. The upper surface of the spherical crown lining plate (3) is provided with a convex spherical surface matching the concave spherical surface of the upper seat plate (1), and its upper surface is inlaid with a first spherical slide plate (2). The spherical stainless steel mirror on the lower surface of the upper seat plate (1) and the first spherical slide plate (2) inlaid on the upper surface of the spherical crown lining plate (3) cooperate with each other to form a third rotating friction pair.

5. The variable damping friction pendulum seismic isolation support according to claim 1, characterized in that: The bottom of the upper seat plate (1) is provided with a first annular boss (102), and the bottom of the first annular boss (102) is provided with a plurality of first pin holes (101) at intervals. The first limiting ring (5) is a circular structure with a first through hole (52) in the middle. The first through hole (52) is circular, and a second pin hole (51) is provided on the outer ring of the first limiting ring (5) corresponding to the position of the first pin hole (101). The two are connected through a first shear pin (4) to achieve a fixed connection between the first limiting ring (5) and the upper seat plate (1).

6. A variable damping friction pendulum seismic isolation bearing according to any one of claims 1 to 5, characterized in that: When the support is a fixed support, a second annular boss (1102) is provided on the top of the lower seat plate (11), and a plurality of fourth pin holes (1101) are provided at intervals on the top of the second annular boss (1102). The second limiting ring (9) is a circular structure with a second through hole (92) in the middle. The second through hole (92) is circular, and a third pin hole (91) is provided on the outer ring of the second limiting ring (9) corresponding to the position of the fourth pin hole (1101). The two are connected through a second shear pin (10), thereby realizing a fixed connection between the second limiting ring (9) and the lower seat plate (11).

7. A variable damping friction pendulum seismic isolation bearing according to any one of claims 1 to 5, characterized in that: When the support is a fixed support, the middle steel lining plate (7) is a cylinder, and the outer side wall of the top thereof is provided with a circular first limiting protrusion (71), the size of which is adapted to the first through hole (52), and the outer surface of the first limiting protrusion (71) is an arc surface. The middle outer side wall of the middle steel lining plate (7) is provided with a circular second limiting protrusion (72), which abuts and cooperates with the second through hole (92) of the second limiting ring (9).

8. A variable damping friction pendulum seismic isolation bearing according to any one of claims 1 to 5, characterized in that: When the support is a movable support, the second limiting ring (9) is a circular structure with a second through hole (92) in the middle. The second through hole (92) is polygonal, with arc chamfers between adjacent side walls, and a pair of opposite inner side walls are provided with a stainless steel plate (93).

9. A variable damping friction pendulum seismic isolation bearing according to any one of claims 1 to 5, characterized in that: When the support is a movable support, a polygonal second limiting protrusion (72) is provided on the outer side wall of the middle portion of the intermediate steel lining plate (7), the size of which is adapted to the second through hole (92), and two adjacent side walls of the polygonal second limiting protrusion (72) are provided with arc chamfers, wherein two opposite side walls are fixedly mounted with a sliding bar (73), and a sliding friction pair is formed between the sliding bar (73) and the stainless steel plate (93) on the second limiting ring (9).

10. A variable damping friction pendulum seismic isolation bearing according to any one of claims 1 to 5, characterized in that: The friction coefficient between the first spherical slide (2) and the stainless steel mirror surface is 0.05-0.08, the friction coefficient between the second spherical slide (6) and the stainless steel mirror surface is not greater than 0.03, and the friction coefficient between the third spherical slide (8) and the stainless steel mirror surface is not greater than 0.

03.

11. The variable damping friction pendulum seismic isolation support according to claim 10, characterized in that: The first spherical slide plate (2) and the third spherical slide plate (8) are made of ultra-wear-resistant polymer slide plate material and form a friction pair with a stainless steel mirror surface. Under the test condition of no silicone grease lubrication, the cumulative linear wear rate of 50 km of reciprocating sliding is less than 10 μm / km, the ultimate compressive strength is ≥200 MPa, the allowable compressive stress is ≥50 MPa, and there is no damage under the rapid shearing action of 500 mm / s.

12. A variable damping friction pendulum seismic isolation bearing according to any one of claims 1 to 5, characterized in that: The first shear pin (4) and the second shear pin (10) are set with different shear forces, wherein the second shear pin (10) is sheared preferentially under the action of an E1 earthquake, while the first shear pin (4) remains intact; under the action of an E2 earthquake, both the first shear pin (4) and the second shear pin (10) are sheared, thereby achieving graded energy dissipation and displacement control.

13. A variable damping friction pendulum vibration isolation method, characterized in that: The invention is realized by applying the variable damping friction pendulum seismic isolation support according to any one of claims 1 to 12, comprising: S100: Under normal operating conditions, the bearing mainly relies on the first and second rotating friction pairs to work together to achieve flexible longitudinal or lateral sliding. At this time, the third rotating friction pair remains stationary. The first rotating friction pair uses a smaller friction coefficient, which allows the bearing to significantly reduce the additional force generated by sliding during the sliding process, ensuring its long-term safe and stable operation. At the same time, the first equivalent seismic isolation radius formed by the first and second rotating friction pairs is large, which effectively reduces the amount of lift at the beam end during normal use of the bridge, greatly improving the smoothness of the road surface. S200: When encountering working conditions such as earthquakes, the first rotating friction pair and the second rotating friction pair are activated first and coordinately rotated and slipped by virtue of their smaller friction coefficient and larger first equivalent seismic isolation radius, thereby dispersing and consuming earthquake energy; S300: As the earthquake force continues to act, when the bearing slides to the limit position of normal displacement, that is, after the limit is formed between the lower seat plate (11) and the middle steel lining plate (7), the second rotating friction pair and the third rotating friction pair begin to work in relay cooperation. The third rotating friction pair adopts a larger friction coefficient, and the second equivalent seismic isolation radius formed by the second rotating friction pair and the third rotating friction pair is smaller, which can generate a larger horizontal damping force, thereby improving the horizontal damping performance of the bearing, so that it can effectively absorb and dissipate seismic energy in an earthquake, control the displacement of the bridge, avoid damage to the bridge structure due to excessive displacement, and provide reliable safety protection for the bridge in earthquake disasters.

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