KR20200092014A - Elastomeric Bearing Pad equippied with the Wedges broken in a Strong earth-quake - Google Patents

Abstract

The present invention relates to an elastic support with a lower wedge broken in a range of earthquake force and, more specifically, to an elastic support, which is smoothly applied to general bridge behavior including movement, rotation and deflection during ordinary days, allows an upper wedge resisting a critical point of elastic movement and wind pressure caused by a temperature difference by a climate change to be separately attached thereto, and is designed such that a danger cross-section in which the lower wedge interlocked with the upper wedge is positioned between broken grooves in a destruction stress point so as to absorb and mitigate impact of great earthquake horizontal force generated in case of earthquakes by using free shear deformation of an elastic pad instead of critical resistance of a fixing wedge, thereby damping the earthquake horizontal force which is an original function of the elastic pad after only absorbing the same without the lower wedge in case of the earthquakes. Thus, the elastic support can safely protect a bridge.

Description

Elastic support where the lower wedge breaks in the seismic range {Elastomeric Bearing Pad equippied with the Wedges broken in a Strong earth-quake}

The present invention relates to an elastic support installed on a bridge, and in more detail, normally adapts to general bridge behavior including movement, rotation, deflection, etc., and resists at the limits of stretching and wind load due to temperature difference due to climate change. The upper wedge is attached separately, but the lower wedge interlocked with the upper wedge in order to absorb and cushion the shock by utilizing the free shear deformation of the elastic pad rather than the limit resistance of the fixed crusher for the tremendous seismic horizontal force generated during an earthquake. As the dangerous section located between the fracture grooves facing each other reaches the fracture stress point, it is installed so that it breaks when the earthquake occurs, so the lower wedge breaks in the upper and lower directions and does not interfere with the upper wedge. It relates to an elastic bearing that absorbs only and then attenuates it to provide an elastic support that safely protects the bridge, and the horizontal wedge breaks in the seismic force range by quantitatively calculating the seismic horizontal force.

In general, between the bridge girder constituting the superstructure of the bridge and the bridge constituting the substructure, it receives the vertical load acting on the superstructure, and the relative displacement and horizontality due to seasonal temperature changes, wind, earthquake, etc. An elastic bearing is installed to accommodate the shear displacement in the direction to extend the endurance life of the bridge.

The elastic bearing plays an important role in improving the durability of the bridge by absorbing various loads applied to the upper structure of the bridge, that is, the load of the bridge itself and the impact load and noise of the vehicle.

Therefore, the elastic bearing installed between the shift or bridge and the superstructure accommodates the load acting on the superstructure, and accommodates the relative displacement caused by temperature changes, impacts such as wind and earthquakes, and the shear displacement acting horizontally, resulting in the endurance life of the bridge. It is installed to extend.

In the elastic support, an elastic pad made of an elastic material is inserted between an upper plate fixed to the upper structure with an anchor and a lower plate fixed with an anchor to the pier.

When the vertical load is applied to the elastic bearing, the elastic pad expands and exerts a buffering force and resistance, and when a shear deformation in the horizontal direction occurs, the elastic pad is deformed to about 150% in thickness and shear deformation. Resists.

In the elastic support, horizontal displacement in a specific direction is allowed, but in order to limit horizontal displacement in other directions, the upper wedge protrudes downward in the upper plate and the lower wedge protrudes upward in the lower plate. , An elastic pad is positioned between the upper wedge and the lower wedge.

The elastic support constitutes a movable one-way elastic support in which the upper and lower wedges are installed only in the left-right or front-rear directions, so that the upper and lower wedges can move only in the direction in which the upper and lower wedges are not installed. Because it takes, movement is limited.

In addition, the horizontal displacement in all directions is limited to the fixed elastic support in which the upper and lower wedges are installed in the front, rear, left, and right directions from the elastic support.

However, the function of limiting the displacement in the horizontal direction from the one-way elastic support or the fixed elastic support should be exerted only in normal cases, but the upper and lower wedges are damaged even when a large external force threatening the safety of the bridge itself occurs, such as an earthquake. Since it is installed without falling out, the elastic bearing accommodates a larger shear strain.

If, in the event of an earthquake, the upper and lower wedges of the elastic bearing resist without falling off, the seismic load is concentrated on the fixed end of the bridge, as in the case of the steel bearing, so that the horizontal force greater than the horizontal force considered in the design of the bridge shears on the bridge itself. There is a risk of collapse.

To this end, the upper and lower wedges are easily broken at a certain load, and means for easily replacing or repairing the upper and lower wedges have been proposed.

The upper wedge is fixed to the bottom surface of the upper plate by welding, and the lower wedge is fixed to the upper surface of the lower plate by welding.

The upper and lower wedges fixed by welding as described above are limited when horizontal displacement occurs, but when horizontal displacement of more than the set load occurs, the upper wedge and the lower wedge should interfere and the lower wedge should break and fall out, but fixed by welding Because it did not break easily (破斷), if the lower wedge is not broken, there is a problem that the bridge collapses because it does not absorb and buffer the shock during an earthquake.

First, since the upper and lower wedges are fixed by welding, it is difficult to adjust to break and break at the fracture stress point, which is the limit resistance of the earthquake horizontal force.

In the process of fixing the upper and lower wedges by welding as described above, it is necessary to adjust the fracture stress point, which is the limit resistance, according to the width of the welding part, but it is not easy to adjust by welding.

Second, in order to fix the lower wedge or the upper wedge to the upper and lower plates, there was a hassle of performing a welding operation.

That is, there is a difficulty in performing an elaborate welding operation so that it breaks when a set load occurs.

Republic of Korea Patent Application No. 10-2008-0043553 "elastic support for bridges"

The present invention for solving the above problems, when the lower wedge among the upper and lower wedges attached to the upper and lower plates respectively reaches the fracture stress point, which is the limit resistance of the seismic horizontal force, the dangerous sections located between the breaking grooves formed on both left and right sides are broken and lowered. The aim is not to interfere with the upper wedge.

That is, an object of the present invention is to facilitate the calculation so that the lower wedge breaks in the lower plate when the seismic level reaches the limit by quantitatively calculating the stresses of the bending and shear loads received by the upper and lower wedges of the elastic bearing.

The present invention as a solution to the above problem, in the elastic support for a bridge, the upper wedge protruding downward from the bottom surface of the upper plate is fixed by welding, and the lower wedge protruding upward from the upper surface of the lower plate is on both sides. A fracture groove is formed to face in the "∠" shape in this inner direction, and a dangerous cross section is located between the fracture grooves so that when the fracture stress point is reached, the lower wedge is broken in the seismic force range. Provide elastic support.

As described above, the elastic support of the present invention secures the upper wedge to the upper plate by welding, the lower wedge is fixed to the upper surface of the lower plate by welding, and then the danger formed in the lower wedge in the process of pressing the lower wedge into the upper wedge When the cross-section reaches the fracture stress point, the lower wedge breaks in the upper and lower directions, and in the event of an earthquake, it absorbs only the seismic horizontal force, which is the unique function of the elastic pad, without the lower wedge, and attenuates it to protect the bridge safely.

The present invention can easily calculate the bending and shear loads received by the upper and lower wedges of the elastic bearing by quantitatively calculating the stress so that the lower wedge fixed to the lower plate breaks in the upper and lower directions when the seismic level reaches the limit. It has an effect.

1 is an exploded perspective view showing a one-way elastic bearing of the present invention.
Figure 2 is a combined perspective view showing the elastic support in one direction of the present invention.
Figure 3 is a perspective view showing the upper plate and the elastic pad removed from the elastic support in one direction of the present invention.
Figure 4 is a perspective view showing a state in which only the upper plate is removed from the one-way elastic bearing of the present invention and the one-way lower wedge and the elastic pad are combined.
Figure 5 is a perspective view showing a broken state of the lower wedge in the one-way elastic support of the present invention.
Figure 6 is a perspective view showing the lower wedge in the elastic support of the present invention.
7 is a plan view showing the one-way elastic support of the present invention.
Figure 8 is a front view showing a one-way elastic support of the present invention.
Figure 9 is a front view showing a broken state of the lower wedge in the one-way elastic support of the present invention.
Figure 10 is an exploded perspective view showing a fixed elastic support according to the present invention.
11 is a perspective view showing a fixed elastic support according to the present invention.
12 is a perspective view showing only the upper plate is removed from the fixed elastic support of the present invention.
13 is a plan view showing a fixed elastic support according to the present invention.

In order to achieve the above objects and effects, the present invention will be described in detail with reference to the accompanying drawings.

Figure 1 is an exploded perspective view showing the one-way elastic support of the present invention, Figure 2 is a combined perspective view showing the one-way elastic support of the present invention, Figure 3 is a perspective view showing the top plate and the elastic pad removed from the present invention one-way elastic support 4 is a perspective view showing a state in which only the upper plate is removed from the one-way elastic support and the one-way lower wedge and the elastic pad are combined.

In the present invention, the elastic support (1) has a lower one in which the lower wedge (5) protrudes upward from the upper surface of the one-way upper wedge (4a) and the lower plate (3) protruding downward from the bottom surface of the upper plate (2). An elastic pad 6 is positioned between the one-way upper wedge 4a after arranging so that the one-way upper wedge 4a is hung on the wedge 5.

The one-way upper wedge 4a protruding downward from the bottom surface of the upper plate 2 is fixed by welding, and the lower surface of the lower wedge 5 protruding upward in the upper surface of the lower plate 3 is in close contact. It is then attached to the lower plate 3 by welding.

The elastic support 1 is a type in which the upper wedge 4a and the lower wedge 5 in one direction are formed in one direction, and the upper wedge 4a and the lower wedge 5 are positioned in the left and right directions, and fixed in the left and right directions. In the front-rear direction, the upper wedge 4a and the lower wedge 5 in one direction are formed in a structure to which only the direction can be moved.

The upper and lower wedges 4a are positioned on both sides of the bottom surface of the upper plate 2, and then the upper surface of the one-way upper wedge 4a is fixed to the bottom surface of the upper plate 2 by welding.

On both sides of the upper surface of the lower plate 3, the lower wedge 5 is correspondingly positioned to face the one-way upper wedge 4a to be caught when a shear force is generated.

The lower wedge 5 is formed with opposing breaking grooves 8 in the shape of "∠" from both right and left sides inward, forming a dangerous section 7 between the breaking grooves 8, and then destroying the sound when an earthquake occurs. When the point is reached, the dangerous section 7 is formed in a structure that breaks, and then the one-way upper wedge 4a attached to the bottom surface is located on the upper plate 2 between the lower wedges 5, and the one-way upper wedge 4a Between the elastic pad 6 is located.

5 is a perspective view showing a state in which the lower wedge is broken in the one-way elastic support of the present invention, FIG. 6 is a perspective view showing a lower wedge in the present invention elastic support, and FIG. 7 shows the present invention one-way elastic support 8 is a front view showing a one-way elastic bearing of the present invention, and FIG. 9 is a front view showing a state where a lower wedge is broken in the one-way elastic bearing of the present invention.

In the present invention, the one-way elastic support (1) is located on the lower left and right wedges (5) on the left and right sides of the upper surface of the lower plate (3), and then fix the bottom surface of the lower plate (3) by welding.

When the lower wedge 5 is assembled as described above, the one-way upper wedge 4a and the lower wedge 5 are alternately positioned in the upper and lower directions, and the elastic pad 6 is seated between the one-way upper wedges 4a. Is formed.

The lower wedge 5 adjusts the value of the maximum shear stress at the fracture stress point at intervals formed between the breaking grooves 8 so that the dangerous section 7 breaks in the upper and lower directions when an earthquake occurs in the lower plate 3.

On the other hand, the bending and shear loads received by the upper wedge 4a and the lower wedge 5 in one direction of the elastic bearing 1 are quantitatively calculated to calculate the stress, and when the seismic level reaches the threshold, the lower wedge in the lower plate 3 The method of calculating the quantity so that (5) breaks is as follows.

Arrangement of upper and lower wedge by direction of seismic force

Comparison of welded wedge and assembled new technology wedge according to seismic force

(When the earthquake occurs, the one-way type with a small number of wedges is selected from the thrust angle (X-X') where the structure is weak)

A) Examine the bending stress of upper and lower parts

Maximum bending stress generated by the wedge welded to the top (σbm)

Breaking force stress (σbn) under the new technology wedge

Coefficient when the maximum bending stress (σbm) generated on the wedge welded to the top and the fracture bending stress received by the new wedge technology

The range of the maximum shear stress that breaks when the earthquake occurs is limited to within 1.01 to 3.99.

B) Review the shear force at the top and bottom

Maximum shear force generated by the wedge welded to the top (τm)

Coefficient of maximum shear force (τm) generated at the wedge welded to the top and fracture shear force (τn) received by the new technology wedge at the bottom

Therefore, the lower wedge meshed with the one-way upper wedge 4a to absorb and absorb shock by utilizing the free shear deformation, which is a unique function of the elastic pad 6, rather than the limiting resistance of the one-way upper wedge 4a, which is caused by an earthquake when the earthquake occurs. When (5) reaches the fracture stress point, the lower wedge (5) is designed so that the dangerous section (7) located between the breaking grooves (8) breaks. It is broken in the upper and lower directions and does not get caught in the upper wedge 4a in one direction, so that the seismic horizontal force is absorbed by the elastic pad 6 to safely protect the bridge.

10 is an exploded perspective view showing the fixed elastic support of the present invention, FIG. 11 is a combined perspective view showing the fixed elastic support of the present invention, and FIG. 12 is a perspective view showing only the upper plate removed from the fixed elastic support of the present invention, FIG. 13 is a plan view showing a fixed elastic support according to the present invention.

Elastic pad (1) of the present invention, the upper and lower plates (2, 3) are stacked, the elastic pad (6) positioned between the fixed upper wedge (4b) of the upper plate (2) elastic pad so that it does not move in all directions The fixed upper wedge 4b is attached in the front, rear, left and right directions of (6), and the fixed upper wedge 4b is a structure that is installed twice as much as the one-way upper wedge 4a.

The lower wedge 5 located on the upper surface of the lower plate 3 is formed to face the breaking grooves 8 in opposite directions from both right and left sides in a state where the bottom surface is fixed by welding, and between the breaking grooves 8 A dangerous section 7 is formed.

The upper plate (2) located on the lower plate (3) is positioned at a fixed upper wedge (4b) in a corresponding position so as to engage the lower wedge (5) located in the front, rear, left and right directions, and then fixed upper wedge (4b) by welding ) Is fixed to the bottom of the upper plate 2, and the elastic pad 6 is positioned between the fixed upper wedges 4a.

The fixed upper wedge (4a) is bent in the shape of an "a", so when the lower wedge (5) is inserted into the bent portion, it remains fixed without moving in all directions, and fixes the tremendous earthquake horizontal force generated during an earthquake. Rather than the limit resistance of the upper wedge 4b, the fixed upper wedge 4b and the lower wedge 5 engaged with the stationary upper wedge 4b are absorbed and absorbed by the use of free shear deformation, which is an intrinsic function of the elastic pad 6, which is a dangerous section at the fracture stress point ( 7) This is designed to break, and when an earthquake occurs, if the lower wedge 5 breaks and breaks in the upper and lower directions around the dangerous section 7, the seismic function of the elastic pad 6 without the lower wedge 5 The bridge is safely protected by absorbing and damping only the horizontal force.

That is, in the present invention, the elastic support 1 has a shorter cross section than the other part of the lower wedge 5, because the dangerous section 7 formed on the lower wedge 5 has a shorter stress point than the other section when the earthquake occurs. And lead to breakage.

In addition, the lower wedge 5 adjusts the fracture stress point and the maximum shear stress point at intervals between the fracture grooves 8 so that they break when an earthquake occurs in the bottom plate 3.

1: Elastic support 2: Top plate
3: lower plate 4a: one-way upper wedge
4b: Fixed upper wedge 5: Lower wedge
6: Elastic pad 7: Hazardous section
8: Breaking groove

Claims (4)

In the elastic support that the elastic pad is located between the upper wedge protruding downward in the lower surface of the upper plate and the lower wedge protruding upward in the upper direction on the lower surface of the upper plate and the lower wedge arranged in the upper and lower wedges,
The one-way upper wedge 4a or the fixed upper wedge 4b protruding downward from the bottom surface of the upper plate 2 is fixed by welding, and the upper wedge protruding upward from the upper surface of the lower plate 3 ( After fixing the bottom surface of the 5) by welding, the right and left sides of the lower wedge 5 are formed with opposing fracture grooves 8 in the inner direction, and a dangerous cross-section between the fracture grooves 8 ( 7) After forming, when the earthquake reaches the breaking sound point, the lower wedge, characterized in that the dangerous section (7) breaks, is an elastic bearing that breaks in the range of the seismic force.
The seismic force of claim 1, wherein the lower wedge (5) adjusts the fracture stress point and the maximum shear stress point at intervals between the fracture grooves (8) to break when an earthquake occurs in the lower plate (3). Elastic support that breaks in range.
The method according to claim 1, wherein the lower wedge (5) has the same structure that can be applied to both the one-way upper wedge (4a) and the fixed upper wedge (4b). The lower wedge breaks in the seismic force range. Elastic support.
The maximum bending stress coefficient of the lower wedge (5) that breaks when the earthquake occurs is in the range of 1.01 to 3.99, and the maximum shear stress coefficient of the lower wedge (5) that breaks is limited to the range of 1.01 to 3.99. Elastic support that the lower wedge to be broken breaks in the seismic force range.

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