Friction pendulum multi-stage isolation bearing based on shear thickening fluid

Abstract

The present invention discloses a friction pendulum multi-stage seismic isolation bearing based on shear thickening fluid, comprising an upper bearing plate fixedly connected to an upper structure and a lower bearing plate fixedly connected to a foundation; a hinged slider is welded to the lower part of the upper bearing, and the hinged slider is connected to the sliding surface of the lower bearing by sliding cooperation; a lateral displacement energy dissipation device is welded to the lower bearing; the lateral displacement energy dissipation device is mainly composed of a cylinder body, a piston, a piston rod, a shear thickening fluid, a ring-shaped baffle and an upper cover; the lower bearing is sealed and fixedly connected to the cylinder body by welding, an annular piston is arranged in the cylinder body, and a shear thickening fluid is filled between the cylinder body and the piston; the ring-shaped baffle is sleeved on the periphery of the hinged slider, and a movable space is left between the ring-shaped baffle and the cylinder body; one end of the piston rod passes through the cylinder body and is welded to the piston, and the other end of the piston rod is fixedly fixed to the ring-shaped baffle by riveting; a sealing ring is arranged between the piston rod and the cylinder body; and an upper cover is welded on the top of the cylinder body to form a sealed cavity. The present invention can rotate freely in all directions, has a large vertical bearing capacity, and has good durability.

Description

Technical Field

[0001] The invention belongs to the technical field of vibration reduction of engineering structures, and in particular relates to a friction pendulum multi-stage seismic isolation support based on a shear thickening fluid with good limiting function and damping energy dissipation characteristics. Background Art

[0002] Earthquake is one of the major natural disasters faced by mankind. my country is one of the countries most seriously affected by earthquakes in the world, and also the country with the most continental strong earthquakes, accounting for about 35% of the world's continental strong earthquakes. Taking the Wenchuan earthquake as an example, the confirmed death toll is 69,227, the missing persons are 17,923, and the direct economic loss is 845.2 billion yuan. Therefore, the research on engineering structure vibration reduction technology has important economic value for the development of society.

[0003] Sliding isolation structure is the first research direction in China. The bearing transfers the seismic energy of the lower structure to the upper structure through the friction of the contact surface. The smaller friction coefficient ensures that the force on the upper structure will not be too large, and the seismic energy is consumed by friction, which has a good isolation and energy dissipation effect. The earliest sliding friction isolation bearing is a polytetrafluoroethylene bearing. The sliding surface is a plane and lacks an automatic reset mechanism. It often needs to be used with an active reset device. In order to overcome this shortcoming, FPS (Friction Pendulum Isolated System) was invented later. The sliding surface is changed from a plane to a spherical surface, but this also increases the seismic force transmitted to the upper structure, and the influence of the input frequency is also increased. At present, the composite isolation system with both reset ability and energy dissipation characteristics is favored by researchers and engineers.

[0004] Shear thickening fluid (STF) is a smart material with excellent performance. The characteristics of STF depend on its shear strain rate. When subjected to high strain rate load, the surface of the contact interface undergoes shear thickening behavior, and its viscosity changes dramatically, even from liquid phase to solid phase. At this time, the shear modulus of STF is much larger than its initial shear modulus. Importantly, when the load is removed, STF can instantly change from solid phase to liquid phase, and this change is reversible. Therefore, the damper based on the material characteristics of STF can quickly and effectively consume the external energy acting on it. Summary of the invention

[0005] In response to the above technical problems, the present invention discloses a friction pendulum multi-stage seismic isolation bearing based on shear thickening fluid, which gives full play to the advantages of STF's passive high energy consumption and the friction pendulum bearing's self-recovery characteristics and good seismic isolation performance, and develops a composite seismic isolation system with both excellent reset ability and energy consumption characteristics, solving the problems of insufficient energy consumption of traditional bearings and limited applicable frequency range.

[0006] The technical solution adopted to achieve the purpose of the present invention is:

[0007] A multi-stage seismic isolation bearing of a friction pendulum based on shear thickening fluid, comprising an upper bearing plate fixed to an upper structure and a lower bearing plate fixed to a foundation; an articulated slider is welded to the lower part of the upper bearing, and the articulated slider is slidably connected to the sliding surface of the lower bearing; a lateral energy dissipation device is welded to the lower bearing; the lateral energy dissipation device is mainly composed of a cylinder body, a piston, a piston rod, a shear thickening fluid, a ring-shaped baffle and an upper cover; the lower bearing is sealed and fixedly connected to the cylinder body by welding, an annular piston is arranged in the cylinder body, and a shear thickening fluid is filled between the cylinder body and the piston; the ring-shaped baffle is sleeved on the periphery of the articulated slider, and a movable space is left between the ring-shaped baffle and the cylinder body; one end of the piston rod passes through the cylinder body and is welded to the piston, and the other end of the piston rod is riveted and fixed to the ring-shaped baffle; a sealing ring is arranged between the piston rod and the cylinder body; an upper cover is welded on the top of the cylinder body to form a sealed chamber.

[0008] Compared with the prior art, the effects and benefits of the present invention are:

[0009] 1. The present invention has excellent energy dissipation properties and self-resetting performance; it solves the problems of insufficient energy dissipation of traditional bearings, limited applicable frequency range, and single-direction movement of bearings. The seismic isolation bearing simultaneously exerts the seismic isolation effect of the friction pendulum and the energy dissipation and shock absorption effect of the energy dissipation device.

[0010] 2. The present invention is adaptable to a wide range of loads. Under the action of a small earthquake, the slider moves on the slideway of the lower support, changing the natural vibration period of the structure and dissipating energy through friction work. Under the action of a large earthquake, the slider moves with a large amplitude. At this time, the collision between the slider and the baffle further drives the piston rod to move, thereby forcing the STF to flow through the gap in the cylinder body and consume energy, ultimately consuming the energy of structural vibration.

[0011] 3. The seismic isolation bearing of the present invention has a simple structure, does not require a large number of connecting parts, and is easy to install and disassemble, thus solving the problem that traditional seismic isolation bearings require a large number of connecting parts and are inconvenient to construct during application. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a schematic diagram of the three-dimensional structure of the seismic isolation support provided by the present invention.

[0013] Figure 2 for Figure 1 AA cross-section diagram.

[0014] Figure 3 for Figure 1 BB cross-section diagram.

[0015] Figure 4 This is a schematic diagram of the internal structure of the seismic isolation bearing provided by the present invention. DETAILED DESCRIPTION

[0016] The following is attached to the instruction manual Figure 1-4 The present invention is further described in detail with reference to the accompanying drawings.

[0017] A friction pendulum multi-stage seismic isolation bearing based on shear thickening fluid, comprising an upper bearing plate 1 fixed to an upper structure, and a lower bearing plate 2 fixed to a foundation; a hinged slider 3 is welded to the lower part of the upper bearing 1, and the hinged slider 3 is slidably connected to the sliding surface of the lower bearing 2; a lateral displacement energy dissipation device is welded to the lower bearing 2;

[0018] The lateral displacement energy dissipation device is mainly composed of a cylinder 4, a piston 5, a piston rod 7, a shear thickening fluid 6, a ring-shaped baffle 8 and an upper cover 9;

[0019] The lower support 2 and the cylinder body 4 are fixedly connected by welding and sealing. An annular piston 5 is arranged in the cylinder body 4, and a shear thickening fluid 6 is filled between the cylinder body 4 and the piston 5. The ring-shaped baffle 8 is sleeved on the periphery of the hinged slider 3, and a movable space is left between the ring-shaped baffle 8 and the cylinder body 4.

[0020] One end of the piston rod 7 passes through the cylinder body 4 and is welded to the piston 5, and the other end of the piston rod 7 is riveted and fixed to the ring-shaped baffle 8; a sealing ring is provided between the piston rod 7 and the cylinder body 4;

[0021] An upper cover 9 is welded on the top of the cylinder body 4 to form a sealed chamber.

[0022] The articulated slider 3 is cylindrical, and its lower surface is a convex spherical surface, which is arranged in the concave spherical sliding surface of the lower support 2, and the sliding surface is coated with polytetrafluoroethylene lubricating material.

[0023] The gap width in the cylinder body 4 is 15-25cm.

[0024] A sealing rubber ring is provided at the connection between the cylinder body 4 and the upper cover 9.

[0025] The gap between the piston 5 and the upper cover 9 is 1-2 mm.

[0026] Shear thickening fluid (STF).

[0027] Working principle: Under the action of an earthquake, the articulated slider moves on the slide of the lower support, changing the natural vibration period of the structure and dissipating energy through friction work. When the structural vibration frequency is high, the movement amplitude of the articulated slider is large. At this time, the contact between the articulated slider and the baffle further drives the movement of the piston rod, and then the piston forces the STF to flow through the gap in the cylinder to consume energy, and finally consumes the energy of the structural vibration. The seismic isolation bearing of the present invention can rotate freely in all directions, has a large vertical bearing capacity and good durability, and gives full play to the advantages of friction pendulum sliding energy dissipation and STF passive, rapid and high energy consumption, etc., meeting the requirements of both good limiting function and damping energy dissipation characteristics.

[0028] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. A friction pendulum multi-stage seismic isolation bearing based on shear thickening fluid, comprising an upper bearing (1) fixedly connected to an upper structure, and a lower bearing (2) fixedly connected to a foundation; characterized in that: A hinged slider (3) is welded to the lower part of the upper support (1), and the hinged slider (3) is connected to the sliding surface of the lower support (2) in a sliding fit; a lateral energy dissipation device is welded to the lower support (2); The lateral displacement energy dissipation device is mainly composed of a cylinder body (4), a piston (5), a piston rod (7), a shear thickening fluid (6), a ring-shaped baffle (8) and an upper cover (9); The lower support (2) and the cylinder body (4) are fixedly connected by welding and sealing, an annular piston (5) is arranged in the cylinder body (4), and a shear thickening fluid (6) is filled between the cylinder body (4) and the piston (5); a ring-shaped baffle (8) is sleeved on the periphery of the hinged slider (3), and a movable space is left between the ring-shaped baffle (8) and the cylinder body (4); One end of the piston rod (7) passes through the cylinder body (4) and is welded to the piston (5), and the other end of the piston rod (7) is fixed to the ring-shaped baffle (8) by riveting; a sealing ring is provided between the piston rod (7) and the cylinder body (4); An upper cover (9) is welded on the top of the cylinder body (4) to form a sealed chamber; The hinged slider (3) is cylindrical, and its lower surface is a convex spherical surface, and is arranged in the concave spherical sliding surface of the lower support (2), and the sliding surface is coated with polytetrafluoroethylene lubricating material; A sealing rubber ring is provided at the connection between the cylinder body (4) and the upper cover (9).

2. The friction pendulum multi-stage seismic isolation support based on shear thickening fluid according to claim 1, characterized in that: The internal gap of the cylinder body (4) is 15-25 cm wide.

3. The friction pendulum multi-stage seismic isolation support based on shear thickening fluid according to claim 1, characterized in that: The gap between the piston (5) and the upper cover (9) is 1-2 mm.

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