Self-resetting three-dimensional damping rubber support based on SMA (Shape Memory Alloy) tows and damping method

Abstract

The invention relates to a self-resetting three-dimensional damping rubber support based on SMA tows and a damping method, and belongs to the field of civil engineering structure damping. The support comprises an upper connecting plate, a lower connecting plate and a shock insulation rubber support, I-shaped sliding rails are fixed to the upper connecting plate and the lower connecting plate respectively, sliding pieces are connected to the sliding rails in a buckled mode, and multidirectional displacement is coordinated through sliding piece connecting rods; the SMA tow system is composed of a fixing rod, a push-pull rod and an annular tow, the two ends of the SMA tow system are anchored to the sliding rail and the connecting rod respectively, and energy consumption and self-resetting are achieved by stretching the tow through a sliding piece. When an earthquake causes horizontal deformation of the support, the SMA tows utilize the hyperelastic hysteretic characteristic to efficiently dissipate energy, automatically recover deformation after the earthquake and drive the sliding piece to reset. According to the invention, the vertical tensile function, the horizontal bidirectional free deformation function and the self-resetting function are integrated, the structure is simplified through the sliding rail-sliding piece module, a complex mechanical device is avoided, and the energy consumption efficiency and the engineering applicability are remarkably improved. And the problems of large residual deformation, poor multidirectional coordination and material fatigue are solved.

Description

Technical Field

[0001] The invention belongs to the field of civil engineering structure shock absorption, and relates to a self-resetting three-dimensional shock-absorbing rubber bearing based on an SMA bundle and a shock absorption method. Background Art

[0002] In the field of construction and bridge engineering, seismic isolation rubber bearings are widely used as important shock-absorbing devices to reduce the impact of earthquakes on structures. Traditional seismic isolation rubber bearings achieve horizontal energy dissipation through the shear deformation and damping characteristics of the rubber layer, but they still have significant defects in vertical tensile capacity, horizontal bidirectional energy dissipation efficiency, and post-earthquake self-reset performance. Studies have shown that the tensile stiffness and compressive properties of rubber materials are quite different, which makes seismic isolation bearings prone to tensile damage when subjected to earthquake overturning moments or strong vertical earthquakes. To solve this problem, the addition of tensile limit devices or the improvement of bearing design are often used in engineering, but these methods often sacrifice the horizontal seismic isolation effect and are difficult to take into account multi-directional seismic requirements.

[0003] Regarding the horizontal bidirectional energy dissipation capacity, although the traditional rubber bearing has a certain shear deformation capacity, its energy dissipation efficiency determined by its damping characteristics is limited, and it is difficult to meet the shock absorption requirements under high-intensity earthquakes. In addition, the longitudinal and lateral deformations under multi-directional earthquakes are not coordinated enough, which can easily lead to excessive deformation in one direction, affecting the overall energy dissipation effect. More importantly, the residual deformation of the rubber bearing after the earthquake cannot be automatically restored and needs to be reset by external intervention, which not only increases the maintenance cost but also causes damage to the structural function. Among the existing improved technologies, the lead core rubber bearing improves the energy dissipation capacity through the plastic deformation of the lead core, but the irreversibility of the lead core makes it easy to fail in multiple earthquakes and cannot achieve self-reset; while the composite bearing based on shape memory alloy (SMA) can use the superelastic properties of the material to achieve the self-reset function, but the existing design is mostly limited to single-direction reset and relies on complex mechanical structures (such as springs, sliders, etc.), resulting in high manufacturing costs and limited durability.

[0004] Further research shows that the existing SMA composite bearings have poor coordination under multi-directional earthquakes, and it is difficult to simultaneously meet the coordinated requirements of vertical tensile resistance, horizontal bidirectional energy dissipation, and self-reset functions. In addition, the high cost of SMA materials, the difficulty in applying prestress, and fatigue problems also limit their practical applications. Although some literature proposes to improve performance by optimizing the structural layout, these solutions still have problems such as low matching accuracy between the slide rail and the sliding part, and the interference of the connecting rod with the rubber deformation, and cannot achieve a stable and reliable three-dimensional shock absorption effect in complex earthquake scenarios. Summary of the invention

[0005] In view of this, the purpose of the present invention is to provide a new type of bearing with a simple structure, controllable cost and the ability to simultaneously improve vertical tensile strength, horizontal energy dissipation and self-resetting capabilities, so as to break through the limitations of the existing technology and adapt to the needs of modern engineering for efficient seismic resistance.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A self-resetting three-dimensional shock-absorbing rubber bearing based on SMA tow, comprising:

[0008] An upper connecting plate, a lower connecting plate, and a seismic isolation rubber bearing disposed between the upper connecting plate and the lower connecting plate, wherein the seismic isolation rubber bearing is used to achieve vertical bearing and horizontal deformation;

[0009] An upper slide rail and a lower slide rail are fixed to the lower surface of the upper connecting plate and the upper surface of the lower connecting plate respectively;

[0010] The upper sliding member and the lower sliding member are respectively slidably connected to the upper sliding rail and the lower sliding rail to achieve vertical tensile resistance and horizontal unidirectional free sliding;

[0011] A sliding member connecting rod, connecting the upper sliding member and the lower sliding member, and used to coordinate the longitudinal and transverse horizontal deformation of the support;

[0012] The invention also provides an SMA module connected between the sliding member connecting rod and the upper and lower sliding rails. The SMA module utilizes superelasticity to provide a self-resetting force and enhance the energy dissipation capacity of the support.

[0013] Optionally, the SMA module includes a first SMA wire bundle fixing rod, a second first SMA wire bundle fixing rod, an SMA wire bundle push-pull rod and an annular SMA wire bundle, wherein:

[0014] The first SMA wire bundle fixing rod is fixed to the upper slide rail or the lower slide rail, the second SMA wire bundle fixing rod is fixed to the sliding member connecting rod, the SMA wire bundle push-pull rod is fixed to the upper sliding member or the lower sliding member, the two ends of the annular SMA wire bundle are respectively connected to the first SMA wire bundle fixing rod and the second SMA wire bundle fixing rod, and the SMA wire bundle push-pull rod slides with the sliding member to achieve stretching deformation;

[0015] The superelastic property of the SMA tow is used to provide a self-restoring force and enhance the energy dissipation capacity of the support.

[0016] Optionally, the upper slide rail and the lower slide rail are both I-beam steel components.

[0017] Optionally, the sliding member connecting rod is arranged at four corners of the support.

[0018] Optionally, the upper slide rail and the lower slide rail are respectively fixed to the upper connecting plate and the lower connecting plate by bolts or welding.

[0019] Optionally, the upper sliding member and the lower sliding member are composed of two C-shaped steel components, which are buckled with the upper sliding rail and the lower sliding rail to limit vertical separation.

[0020] Optionally, the SMA tow is pre-tensioned during installation to enhance the self-resetting capability.

[0021] A shock absorbing method using the above-mentioned support comprises the following steps:

[0022] When an earthquake causes the support to deform horizontally, the sliding member slides along the slide rail, driving the SMA wire bundle to stretch and deform, and absorbing the earthquake energy through superelastic hysteresis energy dissipation.

[0023] Optionally, after the earthquake ends, the elastic restoring force of the SMA tow drives the sliding member to reset, so that the support returns to its initial position.

[0024] The beneficial effects of the present invention are:

[0025] The self-resetting three-dimensional shock-absorbing rubber bearing based on SMA tow proposed in the present invention significantly improves the comprehensive performance of traditional seismic isolation bearings through innovative structural design and material application, which is specifically reflected in the following aspects:

[0026] Highly efficient self-resetting capability and energy dissipation performance

[0027] The superelastic property of the SMA bundle is the core driving force for the displacement recovery of the bearing. When the earthquake causes the bearing to deform horizontally, the slider slides along the slide rail and stretches the SMA bundle, causing it to enter the superelastic deformation stage. In this process, the SMA bundle converts seismic energy into heat energy through the hysteresis energy dissipation characteristics under large strain, significantly improving the energy dissipation efficiency of the bearing. After the earthquake, the superelastic recovery force of the SMA bundle drives the slider to move in the opposite direction along the slide rail, causing the bearing to automatically return to its initial position. Compared with traditional lead rubber bearings that rely on irreversible plastic deformation to dissipate energy, the cyclic stability of the SMA bundle can support reliable reset under multiple earthquakes, effectively avoiding the impact of residual deformation on structural function.

[0028] Coordinated control of vertical tensile strength and horizontal multi-directional deformation

[0029] The tensile strength of traditional seismic isolation rubber bearings is much lower than their compressive strength, and they are prone to tensile failure under strong vertical earthquakes or overturning moments. This solution uses the I-shaped structural design of the upper and lower slide rails, combined with the buckling method of the C-shaped sliding parts, to form a rigid vertical constraint, ensuring that the bearings can still slide freely horizontally while bearing tension. The sliding connecting rods are arranged at the four corners of the bearings, and the displacement of the longitudinal and transverse sliding parts is coordinated through rigid connections, so that the bearings can evenly distribute deformation under multi-directional earthquakes, avoiding the risk of failure caused by local stress concentration.

[0030] Simplified structure and improved engineering applicability

[0031] Existing SMA composite bearings often rely on complex mechanical structures such as springs and sliders to achieve the reset function, which not only increases manufacturing costs, but also affects long-term reliability due to component wear. This solution abandons redundant devices and only completes the energy consumption and reset functions through the synergy of the rail-slider module and the SMA wire bundle. The rail adopts an I-shaped steel component, which is directly fixed to the connecting plate by bolts or welding to simplify the installation process; the buckle design of the C-shaped sliding part reduces friction loss while ensuring vertical tensile stiffness. In addition, the SMA wire bundle is arranged in a ring and pre-tensioned, which further optimizes the reset response speed and material utilization. This highly integrated design makes the bearing both lightweight and highly reliable, suitable for a variety of scenarios such as bridges, high-rise buildings and large-span spatial structures.

[0032] Comprehensive improvement of multi-dimensional seismic performance

[0033] Improvements in the energy dissipation or reset capabilities of traditional seismic isolation bearings in a single direction often come at the expense of other properties. For example, the addition of a tensile limiter may limit the horizontal deformation capacity, while the introduction of a lead core will aggravate the residual displacement. This solution achieves horizontal bidirectional free deformation through the slide rail-slider module, and the symmetrical arrangement of the SMA wire bundles ensures that both longitudinal and lateral deformations can trigger the energy dissipation and reset mechanisms. At the same time, the core functions of the seismic isolation rubber bearing (vertical bearing, shear deformation, and base isolation) are not disturbed by additional structures, thereby fully retaining the seismic isolation advantages of traditional bearings while improving the tensile and reset capabilities.

[0034] Long life and low maintenance cost

[0035] The high fatigue life and corrosion resistance of SMA materials make them stable in long-term earthquake cycles, avoiding the problem of plastic accumulation damage of lead core bearings. The surface of the steel components of the rails and sliding parts can be treated with anti-corrosion to further extend the service life. In addition, the automatic reset feature of the bearing greatly reduces the need for manual intervention after the earthquake, which is particularly suitable for projects in remote areas with inconvenient transportation or difficult maintenance.

[0036] In summary, this scheme has achieved breakthrough optimization in vertical tensile strength, horizontal bidirectional energy dissipation, self-righting efficiency and engineering applicability through the combination of structural innovation and material properties, providing reliable guarantee for structural safety in complex seismic environments.

[0037] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in detail below in conjunction with the accompanying drawings, wherein:

[0039] Figure 1 It is a schematic diagram of the SMA tow deforming to the left;

[0040] Figure 2 Schematic diagram of the undeformed SMA tow;

[0041] Figure 3 It is a schematic diagram of the SMA bundle deforming to the right;

[0042] Figure 4 This is a first-person perspective diagram of this scheme;

[0043] Figure 5 This is another perspective diagram of this scheme;

[0044] Figure 6 This is the axonometric drawing of this scheme;

[0045] Figure 7 Schematic diagram of removing the upper connecting plate for this solution;

[0046] Figure 8 This is a schematic diagram of the slide rail setting method of this solution;

[0047] Fig. 9 This is a schematic diagram of the sliding part structure of this scheme.

[0048] Figure numerals: 1 upper connecting plate, 2 lower connecting plate, 3 seismic isolation rubber bearing, 4 upper slide rail, 5 lower slide rail, 6 upper sliding member, 7 lower sliding member, 8 sliding member connecting rod, 9 first SMA wire bundle fixing rod, 10 second SMA wire bundle fixing rod, 11 SMA wire bundle push-pull rod, 12 SMA wire bundle. DETAILED DESCRIPTION

[0049] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0050] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present invention. In order to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of actual products. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0051] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "front", "rear", etc. indicate the orientation or position relationship, they are based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0052] See also Figures 1 to 9 The implementation method of the self-resetting three-dimensional shock-absorbing rubber bearing based on SMA tow of the present invention is as follows:

[0053] Device assembly and core component connection

[0054] First, the upper connecting plate 1 is fixed to the upper structure (such as a bridge beam or a building frame) by bolts, and the lower connecting plate 2 is connected to the lower foundation in the same way. A seismic isolation rubber bearing 3 is arranged between the lower surface of the upper connecting plate 1 and the upper surface of the lower connecting plate 2, which is bonded to the upper and lower connecting plates by a vulcanization process, and is used to bear vertical loads and provide horizontal shear deformation capacity.

[0055] An I-shaped upper slide rail 4 is installed on the lower surface of the upper connecting plate 1, and a lower slide rail 5 is fixed to the upper surface of the lower connecting plate 2 through the same I-shaped steel member, and both are fastened to the connecting plate by bolts or welding. The I-shaped cross-section design of the upper slide rail 4 and the lower slide rail 5 is adapted to the buckling structure of the C-shaped sliding member.

[0056] The upper sliding member 6 is composed of two C-shaped steel members, which are connected to the I-shaped flange of the upper slide rail 4 by buckling to achieve vertical tensile constraint and horizontal unidirectional free sliding; the lower sliding member 7 adopts the same structure and is buckled with the lower slide rail 5. The sliding member connecting rod 8 is arranged at the four corners of the support, respectively connecting the cross ends of the upper sliding member 6 and the lower sliding member 7, and coordinating the longitudinal and lateral sliding displacements through the rigid rod to ensure the synchronization of multi-directional deformation.

[0057] Installation and configuration of SMA tow system

[0058] In each set of slide rail-slider module, the first SMA wire bundle fixing rod 9 is fixed to the end of the upper slide rail 4 or the lower slide rail 5, and the second SMA wire bundle fixing rod 10 is fixed to the end of the slide connecting rod 8 close to the slide. The SMA wire bundle push-pull rod 11 is fixed to the side wall of the upper slide 6 or the lower slide 7, and moves synchronously with the slide. The two ends of the annular SMA wire bundle 12 are respectively connected to the first SMA wire bundle fixing rod 9 and the second SMA wire bundle fixing rod 10, and the middle part bypasses the SMA wire bundle push-pull rod 11 to form an annular path.

[0059] Specifically, 4 sets of SMA bundle systems are arranged in each horizontal direction (longitudinal and transverse), for a total of 8 sets. During installation, a pre-tension is applied to the SMA bundle 12 to enhance its reset response speed. The superelastic material properties of the SMA bundle 12 cause it to generate hysteresis energy dissipation during stretching deformation, and automatically restore its original length after unloading.

[0060] Workflow and self-reset mechanism

[0061] When an earthquake causes horizontal force, the seismic isolation rubber bearing 3 undergoes shear deformation, driving the upper connecting plate 1 and the lower connecting plate 2 to produce relative displacement. At this time, the upper sliding member 6 and the lower sliding member 7 slide along the upper slide rail 4 and the lower slide rail 5, and the sliding member connecting rod 8 moves accordingly, pushing the SMA wire bundle push-pull rod 11 to stretch the annular SMA wire bundle 12. The SMA wire bundle 12 enters the superelastic deformation stage and dissipates the earthquake energy through large strain hysteresis.

[0062] After the earthquake, the superelastic restoring force of the SMA strands 12 drives the SMA strand push-pull rod 11 to move in the opposite direction, driving the slide member to reset along the slide rail. At the same time, the slide member connecting rod 8 coordinates the displacement of the four corners to ensure that the support as a whole is evenly restored to the initial position to avoid residual deformation.

[0063] Key parameters and optimized design

[0064] The I-shaped cross-sectional dimensions of the upper slide rail 4 and the lower slide rail 5 must match the snap-fit ​​clearance of the C-shaped upper slide member 6 and the lower slide member 7 to ensure smooth sliding and meet the vertical tensile stiffness standards.

[0065] The pre-tension of the SMA tow 12 is determined according to the design displacement, and is usually 20%-30% of the ultimate tension of the tow, so as to balance the reset efficiency and the fatigue life of the material.

[0066] The shear modulus of the seismic isolation rubber bearing 3 and the stiffness of the SMA bundle 12 need to be designed in a coordinated manner to avoid mutual interference between rubber deformation and bundle stretching.

[0067] Application scenarios and extensions

[0068] This bearing can meet the seismic isolation requirements of bridges, high-rise buildings and industrial plants. For long-span bridges, the energy dissipation capacity can be increased by increasing the number of SMA tow groups; for building structures, the length of the slide rail can be adjusted to meet the requirements of different inter-story displacement angles.

[0069] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the present invention.

Claims

1. A self-resetting three-dimensional shock-absorbing rubber bearing based on SMA tow, characterized in that: include: An upper connecting plate (1), a lower connecting plate (2), and a seismic isolation rubber bearing (3) arranged between the upper connecting plate (1) and the lower connecting plate (2), wherein the seismic isolation rubber bearing (3) is used to achieve vertical bearing and horizontal deformation; An upper slide rail (4) and a lower slide rail (5) are respectively fixed to the lower surface of the upper connecting plate (1) and the upper surface of the lower connecting plate (2); The upper sliding member (6) and the lower sliding member (7) are respectively slidably connected to the upper sliding rail (4) and the lower sliding rail (5) to achieve vertical tensile resistance and horizontal unidirectional free sliding; A sliding member connecting rod (8) connects the upper sliding member (6) and the lower sliding member (7) and is used to coordinate the longitudinal and transverse horizontal deformation of the support; And an SMA module connected between the sliding member connecting rod (8) and the upper sliding rail (4) and the lower sliding rail (5), wherein the SMA module utilizes superelasticity to provide a self-resetting force and enhance the energy dissipation capacity of the support.

2. The support according to claim 1, characterized in that: The SMA module comprises a first SMA wire bundle fixing rod (9), a second first SMA wire bundle fixing rod (10), an SMA wire bundle push-pull rod (11) and an annular SMA wire bundle (12), wherein: The first SMA wire bundle fixing rod (9) is fixed to the upper slide rail (4) or the lower slide rail (5), the second SMA wire bundle fixing rod (10) is fixed to the slide member connecting rod (8), the SMA wire bundle push-pull rod (11) is fixed to the upper slide member (6) or the lower slide member (7), the two ends of the annular SMA wire bundle (12) are respectively connected to the first SMA wire bundle fixing rod (9) and the second SMA wire bundle fixing rod (10), and the SMA wire bundle push-pull rod (11) slides with the slide member to achieve tensile deformation; The superelastic property of the SMA wire bundle (12) is used to provide a self-restoring force and enhance the energy dissipation capacity of the support.

3. The support according to claim 1, characterized in that: The upper slide rail (4) and the lower slide rail (5) are both I-shaped steel components.

4. The support according to claim 1, characterized in that: The sliding member connecting rods (8) are arranged at the four corners of the support.

5. The support according to claim 1, characterized in that: The upper slide rail (4) and the lower slide rail (5) are respectively fixed to the upper connecting plate (1) and the lower connecting plate (2) by means of bolts or welding.

6. The support according to claim 1, characterized in that: The upper sliding member (6) and the lower sliding member (7) are composed of two C-shaped steel components, and are buckled with the upper sliding rail (4) and the lower sliding rail (5) to limit vertical separation.

7. The support according to claim 1, characterized in that: The SMA wire bundle (12) applies a pre-tension during installation to enhance the self-resetting capability.

8. A vibration reduction method using the support according to any one of claims 1 to 7, characterized in that: The following steps are involved: When an earthquake causes the support to deform horizontally, the sliding member slides along the slide rail, driving the SMA wire bundle (12) to stretch and deform, thereby absorbing the earthquake energy through superelastic hysteresis energy dissipation.

9. The vibration reduction method according to claim 8, characterized in that: After the earthquake action ends, the elastic restoring force of the SMA wire bundle (12) drives the sliding member to reset, so that the support returns to the initial position.

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