KR20110019587A - Damper separting type seismic isolation device lead - Google Patents

Abstract

PURPOSE: A damper detachable seismic support is provided to enable a user to easily monitor the deformation of the damper in use of the seismic support. CONSTITUTION: A damper detachable seismic support comprises a cover plate(1), a bottom plate(2), an elastic pad(3) and a damper unit(4). The cover plate is fixed on the upper side of a bridge. The bottom plate is installed in the substructure for the bridge support or the bridge post. The elastic pad is made of rubber and the metal plate loaded on the first floor.

Description

Damper separable seismic isolation device {Damper separting type Seismic Isolation Device lead}

The present invention relates to a seismic stand for bridges, and more particularly, has a low vibration energy absorption capacity and a low primary stiffness, which is a disadvantage of the existing elastic bearings that are disadvantageous for the constant loads (eg, wind load, vehicle starting load and braking load, etc.) of the bridge. At the same time, it is difficult to check the shape deformation of lead rods, the size and number of lead rods are limited, and it is related to a new base isolation base that can solve the disadvantages of the existing lead base bearings, which had to be replaced in order to repair the lead rods.

In general, bridge bearings are located at the junctions of bridge decks and bridges or bridges to support loads on vertical loads such as dead loads and live loads, and to slide against horizontal displacements such as temperature expansion and drying shrinkage / creeping of bridge decks. It is a kind of important member in the bridge structure, which has the function of rolling, which can accommodate the rotation of the bridge deck due to the vehicle load, so that the stress caused by the displacement of the superstructure is not transmitted to the alternating and pier excessively. to be.

As the bridge bearing, an elastic plate made of an elastic plate made of rubber or the like forming the initial elastic material layer and an inner reinforcing metal plate constituting the rigid material layer were alternately laminated, and these were bonded to each other and bonded to each other.

However, the elastic bearing protects the structure from earthquake loads by distributing the seismic input acceleration, but it is disadvantageous for the constant loads of bridges (e.g. wind load, vehicle starting load, braking load, etc.) due to low vibration energy absorption capacity and low primary stiffness. There were various problems in practical use.

In other words, the elastic bearing has a wedge (shear key) that controls the constant amount of movement of the upper structure of the bridge to have a direction to the bridge structure, the wedge is a resistance to the supporting load after the wedge is dropped during the seismic load action Because the design assumes that the structure is designed to meet the design theory, the actual support load may not be consistent with the design theory.

Thus, in order to have both the vibration energy absorbing capacity and the ability to reduce and restore the seismic input acceleration of the elastic body in plastic deformation, the elastic plate made of the rubber or the like and the metal plate constituting the rigid material layer are alternately laminated. Lead rubber bearings ("LRBs") have been developed to allow columnar lead to be embedded through an elastomer. In other words, the lead rubber bearing (LRB) is made of a laminated structure of rubber plates and steel plates, but penetrates the lead rods to increase the initial stiffness and attenuation, thereby absorbing seismic loads by lead and plastic behavior of lead. · It is a well-known and common technique that is widely used at home and abroad as an earthquake isolation device to reduce damage of structures during earthquakes by making the structure long-term by dissipation.

However, the conventional napyeonjibyeon has the following problems.

First, since the existing lead napjin bearing has a structure that is installed inside the elastic bearing, it is difficult to check the shape deformation of the lead rod that may occur during the use of the lead napji bearing is difficult to use and maintain.

Next, the existing lead napjin bearing is limited in size and number of lead rods because the lead is installed in the center of the base. In particular, when the magnitude of the earthquake load and the constant load increases, the size and number of lead must be increased.

In another problem, the existing lead-based earthquake bearings had disadvantages in terms of economics because the entire bearing base had to be replaced when deformation of the lead rods occurred due to the external loads such as the constant cyclic load and the earthquake load.

The present invention is to solve the above-mentioned problems, low vibration energy absorption capacity and low primary stiffness to solve the disadvantages of the existing elastic support disadvantageous to the constant load of the bridge and at the same time difficult to determine the shape deformation of the lead rods and the size and number of lead rods Its purpose is to provide a new structure of lead-free support that can solve the shortcomings of the existing lead-free support that had to be replaced in order to repair the lead.

In order to achieve the above object, the present invention, the upper plate is fixed to the bridge upper structure, such as bridge top plate; A lower plate installed on a bridge supporting substructure such as shifts or bridge piers; An elastic pad made of rubber and a steel plate laminated therein at least one layer and interposed between the upper plate and the lower plate to elastically support a load transmitted through the upper structure and to allow horizontal displacement of the bridge top plate; ; A damper-separated seismic isolator is provided comprising a damper unit detachably installed between an upper plate and a lower plate outside the elastic pad installation area.

The effects of the present invention are as follows.

First of all, unlike the existing napjin bearing, the damper is installed so that the damper is exposed to the outside of the elastic bearing. Therefore, the shape deformation of the damper that can occur during the use of the seismic bearing is easily checked with the naked eye. Do.

Next, unlike the existing lead base bearings, which have limited size and number of lead dampers due to the fact that the lead rods are installed at the center of the base plate, the base damping plate of the present invention has a damper made of lead lamps in accordance with the magnitude of the earthquake load and the constant load. Seismic performance can be improved by increasing the size and number, and for this purpose, it is not necessary to increase the overall size of the seismic bearing, which enables economic and reasonable design and construction.

In addition, the seismic isolator according to the present invention is economical because only the damper or damper unit needs to be replaced without replacing the entire support when deformation of the damper, such as lead, occurs due to the external load such as the constant cyclic load and the earthquake load. Excellent and very advantageous for maintenance and maintenance.

In addition, since the damper made of lead, tin, polyurethane, and the like comes out of the elastic pad, the seismic isolator according to the present invention can adjust the horizontal stiffness and the vertical stiffness according to the direction of the normal load and the earthquake load acting on the structure. Do.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, FIGS. 1 to 12.

1 is a perspective view showing the structure of a damper type seismic isolation base according to a first embodiment of the present invention, Figure 2 is a plan view of Figure 1, Figure 3 is a cross-sectional view along the line I-I of Figure 2, Figure 4 It is sectional drawing along the II-II line | wire of FIG.

Referring to these drawings, the damper-separated seismic isolator according to the first embodiment of the present invention includes: an upper plate (1) fixed to a bridge upper structure such as a bridge top plate; A lower plate (2) installed on the bridge supporting lower structure such as shifts or bridge piers; A horizontal displacement of the bridge upper structure while elastically supporting the load transmitted through the upper structure interposed between the upper plate (1) and the lower plate (2) made of rubber and steel plate laminated therein at least one layer therein An elastic pad 3 to allow; It comprises a damper unit (4) detachably installed between the upper plate (1) and the lower plate (2) outside the installation area of the elastic pad (3).

At this time, the damper unit 4 is coupled to the lower surface of the upper plate (1) or the upper surface of the lower plate (2) and the damper fixture (42) having a recessed groove (42a) is inserted into the end of the damper, and the damper fixture It comprises a damper 41, the end of which is positioned and fixed in the recess groove 42a of the 42.

In addition, the damper 41 is made of any one of lead, polyurethane and tin capable of dissipating energy by elastic behavior and plastic behavior, thereby achieving a "straight shape".

That is, according to the present embodiment, the damper 41 made of lead, polyurethane, or tin is installed separately from the elastic pad 3, and has a "straight shape" between the upper plate 1 and the lower plate 2. It is installed to achieve.

The action of the base isolator of this embodiment configured as described above is as follows.

The base isolating base according to the present embodiment is an isolating base which connects the upper structure and the lower structure of the bridge is a base of the structure for separating and mounting the damper 41 made of lead, polyurethane, tin, etc. to the outside of the elastic pad (3).

Accordingly, the damper-separated seismic isolator according to the present embodiment has energy dissipation capacity by the elastic and plastic behavior of lead, polyurethane, and tin, and is in harmony with the restoring ability of the elastic pad 3. Function as.

 That is, the damper type seismic isolation base according to the present embodiment is equipped with a damper 41 having an energy dissipation capacity of lead, polyurethane, tin, etc. in the outer region of the elastic pad 3 to resist constant horizontal force and earthquake load. In addition, the damper 41 having a nonlinear characteristic is combined with the characteristics of the elastic pad 3 having a restoring performance to perform a function of isolating base support.

For reference, tin is basically a material that is stronger than lead, and yield yield is 1.7 times larger than lead, and tin is recrystallized at room temperature like lead. In recent years, efforts have been made to apply tin, which is a substitute for lead, to seismic isolators under the slogans `` reduce the burden on the environment '' and `` reduce the use of harmful substances. '' On the other hand, the polyurethane can be made to function as a damper by adjusting the hardness.

Therefore, the existing lead napjin bearing is difficult to check the shape deformation of the lead rod that may occur during the use of the support because the lead rod is installed inside the elastic pad, there is a difficulty in useability and maintenance, according to the present embodiment Damper type seismic isolation base is a structure that is installed so that the damper 41 made of lead rod, polyurethane, tin, etc. is separated from the elastic pad (3) to be exposed to the outside, the shape deformation can be visually confirmed and easy to maintain.

In addition, the existing lead nap base bearing is limited to the size of the lead rod and the number of installations because the lead rod is installed at the inner center of the elastic pad, and accordingly, the size and number of lead should be increased as the magnitude of the earthquake load and the constant load increases. In this case, the size of the elastic pad must be increased, so the overall size of the base support base must be increased.

However, the damper-separated seismic isolator according to this embodiment adjusts the size and number of dampers 41 made of lead rods, polyurethane, or tin in accordance with the magnitude of the earthquake load and the constant load, thereby appropriately disposing the entire bearing. The desired performance can be achieved without increasing the size.

In other words, by adjusting dampers of different specifications or increasing the number of installations in response to the magnitude of the earthquake load and the constant load, the seismic isolator can exhibit the desired performance, thereby enabling economical and rational design and construction.

In addition, the existing lead surface bearings have to be repaired by replacing the entire lead surface bearings when deformation of the lead rod inside the elastic pad occurs due to external loads such as constant repetitive loads and earthquake loads. The base isolator is very excellent in terms of economics because it is necessary to replace only the damper 41 separated from the elastic pad (3) when the replacement is necessary to check the shape change of the damper 41 while leaving other parts intact.

In addition, since the damper 41 made of lead, tin, polyurethane, or the like comes out of the elastic pad, the seismic isolator according to the present invention can adjust the horizontal and vertical stiffness according to the direction of the normal load and the earthquake load acting on the structure. It is also advantageous for design.

As described above, the damper-separated seismic isolator according to the present invention eliminates the wedge applied to the existing elastic bearing, and instead of installing a damper 41 having energy dissipation capacity such as lead, polyurethane, tin, etc., an additional cost By changing the existing elastic bearing to seismic isolator which absorbs and dissipates seismic loads, it is possible to induce economical design of the bridge substructure to reduce the cost of bridge construction and improve seismic performance.

5 to 10 are perspective views showing the damper-separated seismic isolation base and its damper unit according to the second to fourth embodiments of the present invention. Small bridges made of "S-shaped", "C-shaped", "U-shaped", etc. instead of the "straight-shaped" of the first embodiment and varying in shape depending on the size of the superstructure moving amount, constant load, and earthquake load. In addition, since it can be applied to long bridges, it shows excellent applicability.

Figure 11 is a perspective view showing another embodiment of the damper fixture of the present invention, Figure 12 is a plan view showing a coupling state of the damper fixture of Figure 11, the damper fixture 42 of the present embodiment is a structure divided into two halves to the left and right As the parts divided left and right are joined to each other, the recess groove 42a into which the end of the damper 41 is inserted is completed.

Therefore, according to the present embodiment, when the damper 41 is replaced due to the separate damper fixture 42, the damper 41 can be separated in a state in which only one part of the damper fixture 42 is released. Therefore, partial replacement work can be performed more easily.

13 illustrates the behavior of the damper-separated seismic isolator according to each embodiment of the present invention as shown in FIG. 13.

Referring to FIG. 13, resistance to initial stiffness of lead is applied to short-term loads acting at high speeds such as wind load, braking load, and earthquake load to resist shaking of the bridge structure and lead to long-term load caused by temperature change of the bridge deck. Due to the creep deformation property, it resists with small yield stiffness and does not affect the substructure.

Therefore, the damper-separated lead seismic isolator of the present invention exhibits excellent performance as a seismic isolator of a long bridge, and thus is suitable for seismic bearing of a new bridge, and is suitable for improving performance of an existing bridge to which seismic design is not applied.

On the other hand, the damper-separated seismic isolator of the present invention, by changing the cross-sectional shape of the lead, tin or polyurethane damper can adjust the horizontal and vertical stiffness. By changing the horizontal stiffness (adjusting the cross-sectional shape and size), it is possible to induce reasonable and economical design in the structure design by appropriately changing the rigidity according to the direction of the constant load and the seismic load acting on the structure. The cross-sectional shape may be any cross-sectional shape as well as a circular shape shown in the embodiment drawing, a rectangle, a rounded rectangle, a pentagon, an octagon, an ellipse, a track shape, and the like.

In other words, the conventional lead flat needles have a circular cross-section only, so that they cannot be usefully applied depending on the direction and size of the load, but the damper is rectangular, rounded rectangle, pentagon, It can be octagonal, elliptical, or track shape, so that the cross-sectional shape can be changed usefully according to the direction and size of the load.

In other words, structures such as bridges are analyzed by modeling them as elements in three-dimensional space (mainly X direction: longitudinal direction, Y direction: transverse direction, Z direction: vertical direction).

At this time, the load acting on the structure such as the bridge is divided into normal load and earthquake load, and the normal load is fixed load acting in the direction of gravity like wind weight, wind load acting horizontally, starting load and braking load of the vehicle, etc. It is divided into. In the case of earthquake loads, the civil engineering design specification (road bridge design criteria) of Korea is specified to consider only horizontal loads (vertical and lateral) (except vertical loads).

The seismic isolator is a device to prepare for the case of earthquake load once every several hundred years and the purpose is to reduce the earthquake damage on the structure by absorbing and dissipating the earthquake load, but the seismic isolator should be safe at all times.

Since the wind load is a load acting on the side of the bridge (lateral direction), only the stiffness (primary stiffness) of the lateral damper is theoretically required to withstand the constant wind load.

In the case of the starting load and the braking load, which are the longitudinal loads, theoretically, only the longitudinal rigidity of the damper is required. That is, the magnitude of the horizontal load acting on the structure is measured according to the road bridge specification, and the shape change is made according to the magnitude of the damper to appropriately adjust the stiffness. For example, if the load acting on a structure is dominant in wind load, economical design can be induced by increasing the lateral stiffness of the damper of the present invention and making the longitudinal stiffness relatively small.

The present invention is not limited to the above embodiments, and various changes and modifications can be made in various forms without departing from the scope of the technical spirit of the present invention. For example, in the drawings of the present embodiment, but only one damper unit 4 is shown on one side, it is a matter of course that several damper units may be installed on one side instead of only one.

Accordingly, the rights of the present invention are not limited to the embodiments described above, but are defined by what is stated in the claims, and those skilled in the art can make various modifications and adaptations within the scope of the claims. It is self evident.

As described above, the seismic isolator of the present invention is easy to check the deformation of the damper that may occur during use because the damper, such as lead is mounted on the outside, very convenient to use and maintenance, the size of earthquake load and constant load As the size and number of lead dampers can be increased to improve seismic performance, economical and reasonable design and construction are possible, and deformation of lead dampers can be caused by external loads such as cyclic loads and earthquake loads. Even if only the damper or damper unit needs to be replaced without replacing the whole support, the economic feasibility is very excellent, and thus the industrial applicability is very high.

1 is a perspective view showing the structure of a damper type seismic isolation base according to a first embodiment of the present invention;

2 is a plan view of FIG. 1

3 is a cross-sectional view taken along line II of FIG. 2.

4 is a cross-sectional view taken along the line II-II of FIG.

5 is a perspective view showing a damper-type seismic isolation base according to a second embodiment of the present invention;

Figure 6 is an enlarged front view of the damper unit of Figure 5

7 is a perspective view showing a damper-type seismic isolation base according to a third embodiment of the present invention;

8 is an enlarged front view of the damper unit of FIG. 7;

9 is a perspective view showing a damper-type seismic isolation base according to a fourth embodiment of the present invention;

10 is an enlarged front view of the damper unit of FIG.

11 is a perspective view showing another embodiment of the damper fixture of the present invention

12 is a plan view illustrating a coupled state of the damper fixture of FIG.

Explanation of symbols on the main parts of the drawings

1: upper plate 2: lower plate

3: elastic pad 4: damper unit

41: damper 42: damper fixture

42a: Indentation groove

Claims (5)

An upper plate fixed to a bridge upper structure such as a bridge top plate; A lower plate installed on a bridge supporting substructure such as shifts or bridge piers; An elastic pad made of rubber and a steel plate laminated therein at least one layer and interposed between the upper plate and the lower plate to elastically support a load transmitted through the upper structure while allowing horizontal displacement of the bridge upper structure. Wow; And a damper unit detachably installed between the upper plate and the lower plate outside the elastic pad installation area. The method of claim 1, The damper unit, A damper separation type comprising: a damper fixture fastened to a lower surface of an upper plate or an upper surface of a lower plate and having a recess groove into which an end of the damper is inserted, and a damper fixed at an end thereof to the recess groove of the damper fixture. Base isolation. The method of claim 2, The damper is a damper type seismic isolation base, characterized in that made of any one of lead, polyurethane, tin capable of elastic behavior and plastic behavior. The method of claim 3, wherein The damper is a damper type seismic isolation base, characterized in that forming any one of a straight, S-shaped, C-shaped, U-shaped. The method of claim 2, The damper fixture is a damper-separated seismic isolation, characterized in that the structure is divided into left and right sides.

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