CN104278620A - Resettable roll-in type swinging seismic-isolation pier stud with flanges - Google Patents

Abstract

The self-resetting ball-entry swinging pier with wings is a self-resetting shock-isolation structure of the swinging pier, which includes a main beam, a pier, a cap, a semi-protruding spherical Pier bottom, pier wing plate, rubber cushion, hollowed out hemispherical cap, shape memory alloy shear bolt, oblique section stopper. It changes the consolidation of the pier and the cap to a hinge that can produce swing. The spherical pier bottom of the bridge pier is embedded in the hollow hemisphere on the top of the cap. On both sides of the upper part of the spherical pier bottom of the pier are pier flange plates, and the flange plates are anchored to the caps through shape memory alloy shear bolts. The rubber pad is arranged between the semi-protruding spherical pier bottom and the hollowed out hemispherical top, between the cap and the pier flange, and between the side of the pier flange and the cap block. The invention separates the bridge pier column from the foundation, swayes and filters the seismic energy, and protects both the bridge pier and the foundation; the structure has good social and economic benefits and is worthy of popularization and application.

Description

Self-resetting ball-entry swinging seismic isolation pier with wings

technical field

The invention relates to the field of seismic isolation technology of bridge engineering and river crossing engineering, in particular to a self-resetting swinging seismic isolation pier.

Background technique

Most areas in my country are located in earthquake-prone areas, especially in North China and Southwest China, which are still strong earthquake areas. When constructing structures in these areas, it is necessary to consider the anti-seismic performance of structures and adopt reasonable structural forms to reduce the damage caused by earthquakes. The recent major earthquakes at home and abroad have shown the serious consequences of bridge engineering damage. Effective anti-seismic measures must be taken to reduce the damage of bridges and keep the traffic lifeline unimpeded in earthquake relief and post-earthquake reconstruction. According to different anti-seismic mechanisms of structures, it can be divided into three methods: "anti-seismic", "shock absorption and energy dissipation" and "seismic isolation". The seismic isolation design of the bridge is mainly to replace the traditional bridge bearings with various seismic isolation bearings between the upper and lower structures of the bridge, so as to prolong the natural vibration period of the structure and stagger the frequency band where the seismic energy is concentrated, and at the same time dissipate part of the seismic energy. The ductile seismic design of bridges mainly utilizes the plastic deformation of bridge piers, but it is difficult to repair damage to the plastic hinge area of bridge piers, which may lead to bridge structure collapse in severe cases. In the high-intensity area, for medium-short bridge piers, in order to ensure safety when the bending moment in the plastic hinge area is too large, it is very uneconomical to increase the cross-sectional area, and it is difficult to guarantee the ductility. In view of the above problems, this paper applies the idea of seismic isolation to the bridge pier, and proposes a self-resetting seismic isolation structure of swinging pier columns. The pier column isolation structure can effectively release the bending moment at the bottom of the pier, so no plastic hinges will be formed at the bottom of the pier, effectively controlling the response of the pier in the earthquake, thereby protecting the bridge and achieving the purpose of the bridge's seismic design.

Contents of the invention

In order to solve the problems of bridge piers in the aseismic design of bridges described in the background technology, the present invention proposes a self-resetting swaying pier isolation structure, which can improve the aseismic capacity of the bridge and can be repaired quickly after the connection is damaged. Realize the joint application of "energy dissipation" and "seismic isolation" in the anti-seismic of bridge piers, effectively control the damage of the structure under the action of earthquakes, and ensure the recoverable function of the structure.

In order to achieve the above purpose, the technical solution adopted by the present invention is a self-resetting ball-into-wing swinging seismic isolation pier, which is a self-resetting vibration isolation structure of a swinging pier, which includes a main Beam 1, pier 2, cap 3, semi-protruding spherical pier bottom 5, pier wing plate 6, rubber cushion 7, hollowed hemispherical cap cap 8, shape memory alloy shear bolt 10, oblique section stopper 12. It changes the traditional way of connecting the pier beam to the pier beam consolidation, and changes the consolidation of the pier 2 and the cap 3 to a swingable hinge.

The bottom of the pier 2 is prefabricated into a semi-protruding spherical pier bottom 5; the top of the cap 3 is prefabricated into a hollowed hemispherical top 8; the pier 2 is connected to the cap 3 in a "ball-in" manner, and rubber pads are filled in between Layer 7 better completes both sliding and turning and protects the contact surface. On both sides of the upper part of the spherical pier bottom of the pier are pier flange plates, and the flange plates are anchored and connected to the caps 3 through shape memory alloy shear bolts 10 . The shape memory alloy shear bolt 10 is positioned and placed through the pre-embedded shape memory alloy shear bolt sleeve 9 , and both ends are anchored by the end anchoring steel plate 11 . There are oblique section stoppers 12 that are higher than the pier flange plates around the platform cap 3, and rubber pads 7 are filled between the oblique section stoppers 12 and the sides of the pier wing plates 6.

The rubber cushion layer 7 is arranged between the semi-protruding spherical pier bottom 5 and the hollowed hemispherical top 8, between the cap 3 and the pier wing 6, and between the side of the pier wing 6 and the cap block 12 .

The radius R ₁ of the hemisphere of the semi-protruding spherical pier bottom 5 is smaller than the radius of the pier or the minimum size of the section, the concave radius R ₂ of the platform 3 is less than half of the thickness of the platform, and R ₁ is smaller than R ₂ . A rubber cushion layer 7 with a thickness D is filled between the pier wing plate 6 and the cap 3. Through this incompletely fixed connection, the pier column achieves the purpose of "shock isolation".

The thickness D of the rubber layer needs to meet the requirements of the relative deformation of the contact surfaces of the rubber cushion layer 7 and the bearing platform 3 during the swing. There are protruding pier wing plates 6 on both sides of the pier 2, the width L of the pier wing plate 6 is greater than the radius of the pier or the maximum size of the section, and the height H of the pier wing plate 6 is 1/3 to 1/2 of the height of the cap 3.

The pier wing plate 6 and the platform cap 3 are connected by shape memory alloy shear bolts 10 . Shape memory alloy material (SMA) has a unique shape memory effect and phase transition superelastic properties, making it capable of producing large recovery stress and recovery strain. The shape memory alloy shear bolt 10 can provide pulling force and shear force for the bridge pier 2, and help the bridge pier 2 to reset. The shape memory alloy shear bolts 10 are evenly arranged on the pier wing plate 6 .

The platform 3 is surrounded by oblique section stoppers 12, which can be in the form of a new type of anti-seismic stopper; this oblique section stopper 12 is composed of concrete wedges, vertical steel bars, horizontal steel bars, polystyrene foam spacers and anti-bonding thin layers , with resettable and easy repairability. According to the design idea of sacrificial components, the width B of the oblique section stopper 12 meets the structural performance requirements under the design earthquake, and serves as a secondary safety defense line for the pier's seismic resistance to limit excessive displacement when the pier is swaying. In extreme cases, the oblique section stopper Block 12 is breakable, thereby protecting the main body of the bridge structure.

The beneficial effects of the present invention are:

The shock-absorbing structure of the self-resetting swing pier column of the present invention has a remarkable shock-absorbing effect under the action of an earthquake, which is mainly reflected in the following points:

1. Since the connection between the pier and the cap can be simplified as a hinge, the bending moment at the bottom of the pier is released during the earthquake, and the pier and foundation are basically free of damage after the earthquake, and the integrity is good. In addition, the design of existing conventional bridge piers is less changed by sway isolation, which is easy to implement and has a wide range of applications.

2. The ball-in-type connection of the swinging pier column can reset itself under a small turning angle. The rubber cushion is embedded in the connection between the pier and the bearing platform to facilitate swinging, and there are shape memory alloy shear bolts to help reset, and the stoppers around the bearing platform Limit excessive displacement of piers. Therefore, the structure can realize the sway in the earthquake and achieve the effect of earthquake isolation.

3. In the present invention, the traditional pier-beam hinged connection is replaced by consolidation, and no support is provided at the connection between the pier and the main girder, which avoids the girder falling caused by the slippage of the support and the excessive relative displacement of the main girder during the earthquake; at the same time, due to There is a durability problem in the support, and the support needs to be regularly inspected and replaced in time during the service period, and this structure avoids such problems well.

4. While satisfying relevant design specifications, the present invention separates the pier column from the foundation, swaying and filtering earthquake energy, and protects both the pier and the foundation.

5. The design of the present invention makes the pier of the structure less stressed during the earthquake, so the design section and reinforcement of the pier can be reduced; the pier will not be damaged or slightly damaged after the earthquake, and can be used after a little repair, reducing the repair work after the earthquake The volume and economic cost ensured smooth traffic and won precious time for post-earthquake disaster relief and post-disaster reconstruction. Therefore, this structure has good social and economic benefits and is worthy of popularization and application.

Description of drawings

Figure 1 is a schematic diagram of the longitudinal bridge section of the seismic isolation structure of the self-resetting swinging pier column;

Fig. 2 is a cross-sectional schematic diagram of a seismic isolation structure of a self-resetting swing pier column;

Figure 3 is a top view of the self-resetting swing pier from the rubber cushion;

Fig. 4 is a schematic front sectional view of a stopper with an oblique section.

In the figure: 1. Main girder; 2. Pier; 3. Cap; 4. Pier; 5. Semi-protruding spherical pier bottom; 6. Pier wing; 7. Rubber cushion; Table top; 9. Shape memory alloy shear bolt sleeve; 10. Shape memory alloy shear bolt; 11. End anchor steel plate; 12. Oblique section block; L, pier flange width; H, pier flange thickness ; R ₁ , the radius of the ball at the bottom of the semi-protruding spherical pier; R ₂ , the radius of the top ball of the hollowed hemispherical surface; D, the thickness of the rubber cushion; B, the maximum section width of the oblique section stopper.

Detailed ways

The seismic isolation structure of a self-resetting swaying pier column of the present invention under the action of natural disasters such as earthquakes dissipates seismic energy through swaying to achieve the two purposes of "energy dissipation" and "seismic isolation". The structure is mainly used in bridge engineering and river-crossing engineering seismic isolation technology, and can also be used in frame shear wall structures with small height-to-width ratios.

As shown in Figures 1-4, the present invention is a specific embodiment of a self-resetting structure under the action of natural disasters such as earthquakes. , pier wing plate 6, rubber cushion 7, hollowed out hemispherical cap platform top 8, shape memory alloy shear bolt 10, oblique section stopper 12.

For the pier structure that can be self-resetting, the traditional way of connecting the pier beam to the pier beam is changed to the pier beam consolidation, and the consolidation of the pier 2 and the cap 3 is changed to a swingable hinge.

The bottom of the pier 2 is prefabricated into a semi-protruding spherical pier bottom 5; the top of the cap 3 is prefabricated into a hollowed hemispherical top 8; the pier 2 is connected to the cap 3 in a "ball-in" manner, and rubber pads are filled in between Layer 7 better realizes the sliding and turning of both. On both sides of the upper part of the spherical pier bottom of the pier are pier flange plates, and the flange plates are anchored and connected to the caps 3 through shape memory alloy shear bolts 10 . The shape memory alloy shear bolt 10 is positioned and placed through the pre-embedded shape memory alloy shear bolt sleeve 9 , and both ends are anchored by the end anchoring steel plate 11 . There are oblique section stoppers 12 higher than the pier flange plates around the cap 3, and rubber interlayers are filled between the oblique section stoppers 12 and the sides of the pier flanges 6.

The rubber cushion layer 7 is arranged between the semi-protruding spherical pier bottom 5 and the hollowed hemispherical top 8, between the cap 3 and the pier wing 6, and between the side of the pier wing 6 and the cap block 12 .

The radius R ₁ of the hemisphere of the semi-protruding spherical pier bottom 5 is smaller than the radius of the pier or the minimum size of the section, the concave radius R ₂ of the platform 3 is less than half of the thickness of the platform, and R ₁ is smaller than R ₂ . A rubber cushion layer 7 with a thickness D is filled between the pier wing plate 6 and the cap 3. Through this incompletely fixed connection, the pier column achieves the purpose of "shock isolation".

The thickness D of the rubber layer needs to meet the requirements of the relative deformation of the contact surfaces of the rubber cushion layer 7 and the bearing platform 3 during the swing. There are protruding pier wings 6 on both sides of the pier 2. The width L of the pier wings 6 is slightly smaller than the width of the cap 3 and larger than the radius of the pier or the maximum size of the section. The height H of the pier wings 6 is 1/3 to 1/3 2 of the platform 3 height.

The pier wing plate 6 and the platform cap 3 are connected by shape memory alloy shear bolts 10 . Shape memory alloy material (SMA) has a unique shape memory effect and phase transition superelastic properties, making it capable of producing large recovery stress and recovery strain. The shape memory alloy shear bolt 10 can provide pulling force and shear force for the bridge pier 2, and help the bridge pier 2 to reset. The shape memory alloy shear bolts 10 are evenly arranged on the pier wing plate 6 .

The platform 3 is surrounded by oblique section stoppers 12, which can be in the form of a new type of anti-seismic stopper; this oblique section stopper 12 is composed of concrete wedges, vertical steel bars, horizontal steel bars, polystyrene foam spacers and anti-bonding thin layers , with resettable and easy repairability. According to the design idea of sacrificial components, the width B of the oblique section stopper 12 meets the structural performance requirements under the design earthquake, provides a secondary line of defense for the pier's anti-seismic safety, and limits the excessive displacement of the pier when it swings. In extreme cases, the oblique section stopper Block 12 is breakable, thereby protecting the main body of the bridge structure.

Under the action of the earthquake, due to the horizontal overturning moment, the interface between the foundation and the pier column is lifted, and the repeated lifting and returning cause the bridge body to sway, and the internal force (bending moment) at the bottom of the pier is released. The ball-in-type connection can realize smooth swing and position limit of the pier. The shape memory alloy shear bolts 10 dissipate seismic energy during the swing process, constrain the pier flange, and provide restoring force for the pier. Stoppers 12 around the cap limit the excessive displacement of the bridge pier to ensure that the bridge pier resets. The hinge joint between the bottom of the pier and the cap releases the bending moment at the bottom of the pier and reduces the size of the section of the pier. In addition, the shear bolts 10 between the cap and the pier wing are placed and positioned through the sleeves pre-embedded in the foundation and the pier, so they are not exposed, are not easily damaged by aging, can increase their service life, and are easy to replace. This structure no longer uses supports, which solves the problem that traditional bridges need to replace supports during the entire life cycle of the bridge, and greatly improves economic benefits. The self-resetting joint construction method has strong self-adaptability, and under normal loads (such as foundation displacement, vehicle load, vehicle braking force, etc.), there will be no separation between the pier column and the cap. Under the action of small earthquakes, the pier realizes the sway of the structure through the deformation of the rubber cushion, reducing the stress on the main body of the structure; under the action of major earthquakes, a large relative displacement and lift-off occurs between the pier body and the cap. The memory alloy shear bolts help the pier reset, and at the same time, the oblique section stoppers around the cap limit greater swing displacement. Due to the hinged connection between the pier and the cap, the release of the bending moment reduces the earthquake force of the structure, ensuring that the bearing capacity of the structure does not decrease after the earthquake. Therefore, it not only protects the bridge pier column but also protects the cap foundation, and can also prevent falling beams, which can meet the high requirements of the structure's seismic performance. The self-resetting swaying pier-column isolation structure has good performance under normal service loads and accidental earthquake loads, and is worthy of popularization and application in practical engineering.

Claims (6)

1. the ball of Self-resetting can enter the formula band wing and wave shock insulation pier stud, it is characterized in that: this pier stud be a kind of can the isolation structure waving pier stud of Self-resetting, this shock insulation pier stud comprises (5), bridge pier wing plate (6) at the bottom of girder (1), bridge pier (2), cushion cap (3), the spherical pier of semi-convex formula, rubber spacer (7), hollows out hemisphere face cushion cap top (8), marmem shear studs (10), sloping section block (12); Traditional bearing is connected the mode of Dun Liang and changes pier consolidation into by it, bridge pier (2) and the consolidation of cushion cap (3) is changed into and can produce wave hinged;

The bottom of bridge pier (2) is prefabricated at the bottom of the spherical pier of semi-convex formula (5); The top of cushion cap (3) is prefabricated into and hollows out hemispherical top (8); Bridge pier (2) is connected with cushion cap (3) in " ball enters formula " mode, therebetween filled rubber bed course (7) realize both slippage and rotation protect contact surface; At the bottom of the spherical pier of bridge pier, both sides, top are bridge pier frange plates, and frange plate is by marmem shear studs (10) and cushion cap (3) anchor connection; Marmem shear studs (10) positions arrangement by pre-buried marmem shear studs sleeve (9), and anchoring is carried out by end anchorage steel plate (11) in two ends; The surrounding of cushion cap (3) has the sloping section block (12) higher than bridge pier frange plate, filled rubber bed course (7) between sloping section block (12) and bridge pier wing plate (6) side.

2. according to claim 1ly the ball of Self-resetting can to enter the formula band wing and wave shock insulation pier stud, it is characterized in that: described rubber spacer (7) is arranged on (5) at the bottom of the spherical pier of semi-convex formula and hollows out between hemispherical top (8), between cushion cap (3) and bridge pier wing plate (6), between bridge pier wing plate (6) side and cushion cap block (12).

3. according to claim 1ly the ball of Self-resetting can to enter the formula band wing and wave shock insulation pier stud, it is characterized in that: the radius R of (5) hemisphere at the bottom of the spherical pier of semi-convex formula ₁bridge is less than the radius of pier or the minimum dimension in cross section, the depression radius R of cushion cap (3) ₂be less than the half of cushion cap thickness, and R ₁be less than R ₂; The rubber spacer (7) of filling thickness D between described bridge pier wing plate (6) and cushion cap (3), by this not exclusively fixing connected mode, pier stud reaches " every " object of shaking.

4. according to claim 1ly the ball of Self-resetting can to enter the formula band wing and wave shock insulation pier stud, it is characterized in that: the demand of the relative deformation of rubber spacer (7) and cushion cap (3) contact surface when rubber layer thickness D demand fulfillment waves; There is the bridge pier wing plate (6) stretched out bridge pier (2) both sides, the width L of bridge pier wing plate (6) is slightly less than the width of cushion cap (3) and is greater than the maximum size in bridge pier radius or cross section, bridge pier wing plate (6) height H be the cushion cap (3) of 1/3 ~ 1/2 highly.

5. according to claim 1ly the ball of Self-resetting can to enter the formula band wing and wave shock insulation pier stud, it is characterized in that: bridge pier wing plate (6) is connected by marmem shear studs (10) with cushion cap (3); Marmem shear studs (10) can provide pulling capacity and shearing resistance for bridge pier (2), helps bridge pier (2) to reset; Marmem shear studs (10) is evenly arranged on bridge pier wing plate (6).

6. according to claim 1ly the ball of Self-resetting can to enter the formula band wing and wave shock insulation pier stud, it is characterized in that: cushion cap (3) surrounding is sloping section block (12), novel earthquake-proof link stopper form can be adopted; This sloping section block (12) is made up of concrete wedge, vertical reinforcement, horizontal reinforcement, polystyrene foam spacing block and anti-stick thin layer, has resettability and easy prosthetic; The width B of sloping section block (12) meets structural performance demand under site ground motion; there is provided the secondary defence line of bridge pier quake-resistant safety, displacement excessive when restriction bridge pier waves, under extreme case; sloping section block (12) can destroy, thus protection bridge construction main body.