JP3500463B2 - Buffer material and structure for preventing falling bridge using the buffer material - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shock absorbing material and a fall bridge preventing structure installed between a pier and a girder using the shock absorbing material.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 13, a seismic isolation rubber bearing member 1 in which steel plates are laminated in rubber is buried between the bridge piers and girders in the vertical load direction, and Is a pad 2 made of an elastic material that responds to expansion and contraction due to temperature changes of the girder.
Has been placed.

[0003]

However, in the Hyogoken Nanbu Earthquake, the girders and the piers of the viaducts such as railroad bridges and highways having the above-described structure were dropped and the piers were destroyed. Various studies were carried out on it, and the necessity of a cushioning material to reduce seismic force and the necessity of a cushioning material to prevent the girder from falling were proposed.

Therefore, since the breaking point is not clear in a general cushioning material mainly composed of rubber, when a huge force such as an earthquake acts, the structure attached by the reaction force rather than the cushioning material. Or, there is a problem that a secondary destruction occurs in which the opposing structure is destroyed. Even in the case of a small-scale earthquake where the generated load is less than the design load, a large displacement occurs in the cushioning material and girder structure, and rather a displacement occurs in the girder structure that does not cause any trouble and is restored after that. There is a problem that it requires a lot of labor and cost.

[0005]

Therefore, the present invention is characterized in that an elastic body is housed in a rigid body to form a composite cushioning body, and the cushioning body is horizontally arranged on any one of the pier and the girder. It is mounted so as to face the girder so as to buffer the movement of the girder in the horizontal direction.When the generated load is less than the design load, a rigid body with less displacement is used Displacement generated in the girder is within the design allowance to enable quick service of earthquake knowledge, and for large-scale earthquakes that exceed the design seismic intensity, the rigid body ruptures after buckling etc. It has a composite structure that the possible elastic body bears. Further, the elastic body may have a structure in which cloth-like bodies are embedded in layers in order to clarify the breaking point.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of the cushioning material, and FIG. 2 is a plan view. In the figure, 3 is an elastic body, natural rubber,
A cloth-like body 5 made of a woven or non-woven fabric made of natural fibers, synthetic fibers, metal fibers or the like is partially or entirely contained in an elastic member 4 such as a synthetic rubber or a synthetic resin in the horizontal direction of the elastic member 4. And are buried alternately. This embedded state may be over the entire elastic body 3 or may be partial. Note that the shape is a flat columnar body having a circular planar shape in FIG. 2, but may be a truncated cone shape as shown in FIG. 3, or may be an elongated shape having an arbitrary shape such as a rectangular shape or a trapezoidal plane shape. Good.

Reference numeral 6 is a hollow rigid body made of a rigid material such as FRP, synthetic resin, metal or the like, which is placed in close contact with the outer peripheral surface of the elastic body 3 or is arranged with a space therebetween, and its height is elastic. The height is equal to or higher than the height of the body 3. Further, in some cases, as shown in FIG. 4, a lid 7 and / or a bottom plate 8 may be provided to enhance the integrity to obtain high rigidity. Further, as shown in FIG. 5, a fixing flange portion 9 may be provided. May be.

As shown in FIG. 6, the rigid body 6 may be further provided with a breaking portion 10 for concentrating the breakage due to a notch or a groove. The rigidity of the rigid body 6 depends on the structure. The load should be equal to or slightly higher than the design load. The breaking portion 10 makes it possible to quantify the breaking load. When the cushioning material 11 is composed of the elastic body 3 and the rigid body 6 in this way, the load acting in the initial stage is borne by the rigid body 6 having high rigidity, but the displacement generated is small. Therefore, if the rigid body 6 is, for example, FRP, when the buckling point is reached, the displacement progresses while the internal fibers of the FRP are fractured one after another. As a result, the shortage of spring characteristics due to the elastic body 3 is compensated.

Therefore, in the cushioning member 11 formed by the elastic body 3 and the rigid body 6, both the elastic body 3 and the rigid body 6 bear the load after the displacement and the load are matched. In addition, by stacking the cloth-like bodies 5 as described above, the elastic body 3 can not only increase the energy absorption amount but also improve the spring characteristics and clarify the breaking point. Becomes In addition, a fracture progresses in a chained manner due to elongation fracture occurring in a part of the laminated cloth-like bodies 5,
Eventually, the elastic pair will be completely destroyed, and the reaction force at the time of the first break of the cloth-like body 5 is the maximum, and the load decreases as the cloth-like body 5 breaks. In the elastic body 1 as described above, the absorbed energy is not only the strain energy of the elastic material itself but also the breaking energy of the cloth-like body 5, and therefore the absorbed energy is larger than that of a normal single elastic material. Moreover, it becomes possible to clarify the maximum value of the reaction force.

Further, making the rigid body 6 higher than the height of the elastic body 3 is effective in clarifying the buckling failure point of the rigid body 6, but if it is too high, the elastic body 3 will yield after buckling and the elastic body 3 will be bent. The impact phenomenon may occur because the load difference before the action is large. Cushioning material 11 configured in this way
7 is installed between the pier 12 and the girder 13, as shown in FIG. 7, it is possible to design the installation location of the cushioning material 11 in advance in the case of a new installation, but the installation space is narrow in the existing installation. Therefore, the height of the cushioning material 11 is limited, and a high load bearing spring property is required.

Therefore, in order to cope with a high load, when the pier 12 is mounted, if it is fixed to the structure with bolts, the bolts become thicker and the nuts become thicker to form a very huge locking portion as a whole. Since inconvenience occurs, as shown in FIG. 8, the anchor 14 is embedded in the structure,
It is preferable to attach the rigid body 6 by fixing it to the anchor 14.

Further, in consideration of workability, as shown in FIG. 9, if a support plate 15 such as a steel plate is attached to the structure side of the elastic body 3 by adhesion or the like, the positioning becomes easy. Also,
As shown in FIG. 10, by forming the locking portion 16 inside the head of the rigid body 6 at a position matching the height of the elastic body 3, the elastic body 3 can be held and workability is improved. Can be measured.

The cushioning material 11 is, as shown in FIG.
Since there is a supporting wall not only in the longitudinal direction of the girder 13 but also in the width direction of the girder 13 on the pier 12, the end of the girder 13 is installed on the pier 12 so as to be surrounded by the protective wall. Therefore, the cushioning body 11 may be installed in each of the longitudinal direction and the width direction, but as shown in the figure, the cushioning body 11 may be formed in an angle shape in advance and installed on the pier 12.

According to the cushioning material attached between the bridge pier 12 and the girder 13 in this way, when an earthquake occurs, when the seismic intensity of the earthquake is within the design seismic intensity, the girder 13 vibrates and the cushioning material 11 Although the external force is transmitted, since the rigid body 6 is within its elastic deformation, it does not buckle or break, and is immediately restored by the end of the earthquake. As a result, trains and trains that had been stopped due to the earthquake can resume operation immediately after inspecting the facility, and there will be no traffic obstruction due to long-term stops.

If the distance between the tip of the cushioning material 11 and the end face of the girder 13 is large, there is a risk that the swinging of the girder 13 collides with the cushioning material 11 and an impact force is generated.
It is advisable to reduce the distance between the tip of No. 1 and the end face of the girder 13, or to reduce the distance by interposing a liner therebetween. Next, when an earthquake larger than the design seismic intensity occurs, the digit 1
3 in addition to the buckling fracture energy of the rigid body 6 and the high absorbed energy due to the buckling deformation, the cloth body 5 inside the elastic body 3
Absorbs by adding destruction energy such as
In order to prevent the fall of the girder, damage can be minimized by making the degree of convergence of the girder's movement or the phenomenon of destruction to a large extent, and the supporting fuse theory that is effective in preventing the girder's fall is realized. Can be converted.

Further, the breaking load of the shock absorbing material 11 is designed to be lower than or equal to the allowable load of the girder 13 and the bridge pier 12, and the breaking point against the load is clear, so that the breaking load of the girder 13 and the pier 12 is clear. If there is no damage and only movement, return the girder 13 to its original position and add a new cushioning material 11
There will be cases where restoration work is completed simply by installing the.

The function of the cushioning material 11 described above is shown in a graph as shown in FIG. 12, and the section A in which the rigid body 6 elastically deforms, the X point at which the rigid body 6 breaks, and the rigid body 6 breaks. B section in the process, Y section in which the elastic body 3 and the rigid body 6 bear the load, C section in which the cloth-like body 5 embedded in the rigid body 6 is successively broken, and D section until the elastic body 3 is completely broken. It is possible to minimize damage to the girders 13 and bridge piers 12 by elastically deforming within the design earthquake and damaging the cushioning material 11 by self-destruction above the design earthquake.
It will exhibit many functions that conventional spring materials and cushioning materials do not have.

[0018]

According to the present invention described in detail above, the buffer body is constructed by accommodating the elastic body in the rigid body, and the breaking point of both is the allowable load of the structure on the installation side of the buffer body or the structure on the opposite side thereof. Since the structure is set lower than that, when it is installed between the pier and the girder, the rigidity of the rigid body corresponds to the seismic intensity below the design seismic intensity and the seismic intensity above the design seismic intensity Minimize damage to structures such as piers and girders by absorbing the kinetic energy received from structures, such as buckling fracture energy of rigid bodies, strain energy of elastic bodies and fracture energy of laminated fabrics. Has the effect of being able to.

Further, as a result of the above, there is an effect that the amount of work for the restoration work can be reduced and speeded up, and the resumption of traffic can be speeded up.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a cushioning material.

2 is a plan view

FIG. 3 is a cross-sectional view showing another example of the shape of the elastic body.

FIG. 4 is a cross-sectional view showing another example of the shape of the rigid body.

FIG. 5 is a cross-sectional view showing another example of the shape of the rigid body.

FIG. 6 is a cross-sectional view showing another example of the shape of the rigid body.

[Fig. 7] Explanatory diagram provided between the pier and the girder

FIG. 8 is an explanatory view of a state in which a cushioning material is attached to the pier.

FIG. 9 is an explanatory view of a state where a cushioning material is attached to the pier.

FIG. 10 is an explanatory view of a state where a cushioning material is attached to the pier.

FIG. 11 is an explanatory diagram showing an example of the shape of a buffer body.

FIG. 12 is a graph showing the action state of the buffer body.

FIG. 13 is an explanatory diagram of a conventional technique.

[Explanation of symbols]

3 elastic body 4 elastic material 5 cloth 6 rigid body 7 Lid 8 bottom plate 9 Flange 10 Destruction part 11 cushioning material 12 piers 13 digits 14 anchor

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Innovator Nobuyasu Ikoma 1058 Nakao Uozumi-cho Akashi-shi, Hyogo Shibata Industry Co., Ltd. (72) Shinjiro Nishikawa 1058 Nakao Uozumi-cho Akashi-shi, Hyogo Shibata Industry Co., Ltd. (72) Inventor Yasushi Nishimoto 1058 Nakao, Uozumi-cho, Akashi-shi, Hyogo Shibata Industry Co., Ltd. (72) Ink, Mikio Fukuchi 1058 Nakao, Uozumi-cho, Akashi-shi, Hyogo Shibata Industry Co., Ltd. (56) References JP-A-9-105441 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) F16F 7/00 E01D 19/04 101 F16F 15/04

Claims (6)

(57) [Claims] 1. A cushioning material, characterized in that an elastic body is housed in a rigid body, and a breaking point of both is set to be lower than an allowable load of an installation side structure or an opposing side structure thereof. 2. The cushioning material according to claim 1, wherein the elastic body is embedded by alternately laminating the cloth-like body with the elastic material. 3. The cushioning material according to claim 1, wherein the height of the rigid body is made higher than the height of the elastic body. 4. The cushioning material according to claim 1, wherein the height of the rigid body is the same as the height of the elastic body. 5. The cushioning material according to claim 1, wherein a breaking portion is formed in the rigid body. 6. A cushioning body, in which an elastic body is housed in a rigid body, is attached to any one of the pier and the girder in a state of horizontally confronting it, so as to cushion the girder from moving in the horizontal direction. Characteristic falling bridge prevention structure.