JPH09125316A - Preliminary shearing deformation holding device for elastic support device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To execute a hold releasing work of preliminary shearing deformation simply and safely. SOLUTION: This preliminary shearing deformation holding device of an elastic support device is constituted of a fixed member 12 provided on a lower shoe for holding preliminary shearing deformation applied to an elastic shoe, a first taper liner 15 arranged between the fixed member 12 and an upper shoe 1 and movable in the direction of preliminary shearing deformation, a second taper liner 16 arranged between the fixed member 12 and the upper shoe 1, engaged with the first taper liner 15, and movable in the perpendicular direction to the preliminary shearing deformation direction, and a pressing means 32 pressing the second taper liner 16 so as to control the movement.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a preliminary shear deformation holding device for an elastic bearing device. More specifically, in an elastic bearing device arranged between a bridge girder that is an upper structure and a bridge abutment or pier that is a lower structure in a bridge,
The present invention relates to a device for holding a pre-shear deformation applied to an elastic shoe.

[0002]

2. Description of the Related Art In bridges, bridge girders are installed on abutments and piers via bearing devices. As a bearing device, an elastic bearing device in which a rubber shoe is arranged between an upper shoe and a lower shoe is known. In the case of this elastic bearing device, if the bridge girder is composed of concrete girder or prestressed concrete girder,
The bridge girder contracts due to the introduction of prestress, creep, drying, etc., which causes shear deformation of the rubber slag. If such shear deformation persists for a long period of time, it causes breakage and damage of the rubber cake.

For this reason, conventionally, a method has been adopted in which a preliminary shear deformation corresponding to the shrinkage amount of concrete is applied to a rubber shaving in a direction opposite to the shrinking direction. FIG. 9 shows an example of a conventional method. That is, upper shoe 51 and lower shoe 5
The rubber shoe 53 disposed between the second shoe 2 and the second shoe 5 is pre-shear-deformed, and the side block 54 fixed to the lower shoe 52 and the upper shoe 5
The two taper liners 56, 57 are interposed between the end surface of the cutout portion 55 formed in the first taper liner 1 and the taper liner 56,
57 holds the pre-shear deformation. In the elastic bearing device shown in FIG. 9, the upper shoe 51 and the lower shoe 52 are
Are fixed to the bridge girder 60 and the bridge pier 61 via anchor bars 58 and anchor bolts 59, respectively.

When the concrete of the bridge girder 60 is cast and hardened, the taper liners 56 and 57 are pulled out. However, a large load is applied to the taper liners 56 and 57 due to the shrinkage force of concrete, and one of the taper liners must be pulled out using a jack or the like. In addition, when the liner is pulled out, the liner may suddenly pop out, which is dangerous for the work.

[0005]

SUMMARY OF THE INVENTION The present invention has been made on the basis of the above technical background, and has the following objects.

SUMMARY OF THE INVENTION An object of the present invention is to provide a preliminary shear deformation holding device for an elastic bearing device which can easily and safely carry out the pre-shear deformation holding release operation.

[0007]

The present invention employs the following means to achieve the above object.

That is, the present invention relates to an elastic bearing device having an elastic shoe arranged between an upper shoe, a lower shoe and an upper shoe, and a device for holding a preliminary shearing deformation applied to the elastic shoe, A fixing member provided on the lower shoe, a first taper liner arranged between the fixing member and the upper shoe and movable in a preliminary shear deformation direction, and arranged between the fixing member and the upper shoe. And a second taper liner that is engaged with the first taper liner and is movable in a direction perpendicular to the preliminary shearing deformation direction, and a pressing means that presses the second taper liner and restricts its movement. It is in the pre-shear deformation holding device of the device.

Further, according to the present invention, the relationship between the taper angle θ of the first taper liner and the second taper liner and the friction coefficient μ between the tapered surfaces satisfies μ <tan θ. Pre-shear deformation holding device.

According to the present invention, when the pressing of the second taper liner by the pressing means is gradually released, the second taper liner moves in the direction perpendicular to the preliminary shearing deformation direction.
Along with that, the first taper liner moves in the preliminary shear deformation direction, and the deformation holding is released. In particular, if the relationship between the taper angle θ and the friction coefficient μ between the tapered surfaces is set to satisfy μ <tan θ, the second taper liner will move naturally due to the component force of the force acting on the second taper liner in the preliminary shear deformation direction. To do.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. The following embodiments are examples in which the present invention is applied to an elastic bearing device installed between a bridge girder, which is an upper structure in a bridge, and an abutment and a pier, which are lower structures.

FIG. 1 is a plan view showing an elastic bearing device in which a preliminary shearing deformation holding device according to the present invention is incorporated.
In FIG. 1, X indicates the bridge axis direction, and Y indicates the bridge axis orthogonal direction. FIG. 2 is a side view along the bridge axis direction. The elastic bearing device has an upper shoe 1 and a lower shoe 2 made of metal, and upper and lower shoes 1, 2
A rubber shoe 4, which is an elastic shoe, is fixedly arranged between the two via a boss 3. The upper shoe 1 is fixed to a concrete bridge girder 7 via an anchor bar 6. The lower shoe 2 is fixed to the pier 9 via an anchor bolt 8.

Notches 10 of a predetermined length are formed on both sides of the upper shoe 1 along the bridge axis direction X, and each notch 10 has a step 11. Side blocks 12, which are fixing members, are fixed to both sides of the lower shoe 2 along the bridge axis direction X. The upper end of the side block 12 is engaged with the step portion 11 to prevent the upper shoe 1 from rising.

In the elastic bearing device as described above, the rubber shoe 4 is pre-shear-deformed in the bridge axis direction X, that is, in the contraction direction of the bridge girder 7 in a factory or the like, and is held on the bridge pier 9 in a state where the deformation is held by the holding device 13. Is installed. In this embodiment, the holding device 13 is arranged between the side block 12 and the side end surface of the cutout 10.

The holding device 13 includes a mounting bracket 14 and a first bracket.
The taper liner 15 and the second taper liner 16 are included. FIG. 3 is a plan view of the mounting bracket 14, and FIG. 4 is a front view. The mounting bracket 14 has a bottom plate 17, and one end of the bottom plate 17 is provided with a side plate 18 extending upward and downward. A bolt mounting hole 19 for mounting the mounting bracket 14 to the side block 12 is formed in a lower portion of the side plate 18.

At one end of the side plate 18, an extension portion 20 extending in a hook shape is formed on the bottom plate 17. The extension portion 20 is formed with a screw hole 21 for screwing a pressure bolt described later. The inner surface 22 of the side plate 18 is a sliding surface of the second taper liner 16, and a low friction plate (not shown) such as a Teflon (trade name) plate is attached to this inner surface 22 or molybdenum disulfide and Teflon are used. Apply powder to form a low friction layer.

FIG. 5 is a plan view showing the first taper liner 15, and FIG. 6 is a side view. Guides 23, 23 for guiding the second taper liner 16 are formed on both sides of the tapered surface 22 of the first taper liner 15. Tapered surface 2
A low friction layer is formed on 2 by the same material as described above. At one end of the first tapered liner 15, a hook-shaped extending portion 24 is formed on the tapered surface 22 side. An elongated hole 25 for inserting a pressing bolt is inserted into the extending portion 24.
Are formed. A screw hole 26 for a bolt for fixing a plate liner described later is formed at the base end of the extending portion 24.

FIG. 7 is an enlarged plan view showing a state in which the holding device 13 is incorporated in the elastic support device, and FIG. 8 is a front view.
The mounting bracket 14 is fixed to the side surface of the side block 12 by a fixing bolt 28 on the side plate 18. First taper liner 15 and second taper liner 1
6 is mounted on the bottom plate 17 of the mounting bracket 14 in a state in which the rubber shoe 4 is pre-shear-deformed, and is engaged (wedge engagement) with each other by the tapered surfaces 22 and 27. In addition, the first taper liner 15 has an extension 24
Are arranged so as to contact the outer side surface of the extending portion 20 of the mounting bracket 14, whereby the bolt hole 21 and the elongated hole 25 overlap.

The first tapered liner 15 has a tapered surface 22.
A plurality of plate liners 29, 30 are fixed to the surface on the opposite side by bolts 31 penetrating them. The plate liner 29 and the plate liner 30 have different plate thicknesses, and can be made to correspond to a predetermined amount of preliminary deformation by appropriately increasing or decreasing the number of plates.

A pressing bolt 32, which is a pressing means, is inserted into the elongated hole 25 of the first taper liner 15, and the mounting bracket 1
4 is screwed into the screw hole 21. Due to the restoring force of the rubber shoe 4 after the preliminary shear deformation, a component force in the direction Y perpendicular to the bridge axis acts on the second taper liner 16.
And the extension portions 20 and 24 receive the reaction force as a reaction force, so that the pre-shear deformation state is maintained.

After the concrete of the bridge girder 7 is hardened, the holding of the preliminary shear deformation is released. Here, the relationship between the taper angle θ (see FIG. 5) of the first taper liner 15 and the second taper liner 16 and the friction coefficient μ between the taper surfaces 22 and 27 is set so as to satisfy μ <tan θ. Has been done. Preferably, tan θ = 0.12 to 0.18.

Therefore, when the pressing bolt 32 is loosened,
The second taper liner 16 moves outward in the same direction by the component force in the direction Y perpendicular to the bridge axis due to the contracting force of concrete. Further, along with that, the first taper liner 15 moves toward the side block 12 in the bridge axis direction, and the preliminary shear deformation holding is released. After releasing, the holding device 13 is removed. In this way, the preliminary shearing deformation holding can be released easily and safely by only operating the pressing bolt 32.

The above-described embodiment is merely an example, and the present invention can be modified in various ways. For example, although the side block is used as the fixing member, a member different from this may be provided in the lower shoe. Further, the preliminary shearing deformation holding device of the present invention also functions as a temporary fixing jig by incorporating a total of four on both sides of one side block.

[0024]

As described above, according to the present invention, the work of releasing the preliminary shearing deformation can be easily and safely performed.

[Brief description of the drawings]

FIG. 1 is a plan view showing an elastic bearing device in which a preliminary shearing deformation holding device according to the present invention is incorporated.

FIG. 2 is a side view along the bridge axis direction.

FIG. 3 is a plan view showing a mounting bracket.

FIG. 4 is a front view.

FIG. 5 is a plan view showing a first taper liner.

FIG. 6 is a side view.

FIG. 7 is an enlarged plan view showing a state where the holding device is incorporated in the elastic support device.

FIG. 8 is a front view.

FIG. 9 is a diagram showing a conventional example.

[Explanation of Codes] 1 ... Upper shoe 2 ... Lower shoe 4 ... Rubber shoe 7 ... Bridge girder 9 ... Bridge pier 10 ... Notch 12 ... Side block 13 ... Preliminary shear deformation holding device 14 ... Mounting bracket 15 ... First taper liner 16 ... Second taper liner 32 ... Press bolt

Claims (2)

[Claims] 1. An elastic bearing device having an elastic shoe arranged between an upper shoe, a lower shoe and an upper shoe, for holding a pre-shear deformation imparted to the elastic shoe, wherein the lower shoe A first taper liner disposed between the fixing member and the upper shoe and movable in the pre-shear deformation direction; and disposed between the fixing member and the upper shoe, Preliminary shearing of an elastic bearing device comprising a second taper liner that engages with the first taper liner and is movable in a direction perpendicular to the direction of preliminary shear deformation, and a pressing means that presses the second taper liner and restricts its movement. Deformation holding device. 2. The elastic bearing according to claim 1, wherein the relationship between the taper angle θ of the first taper liner and the second taper liner and the friction coefficient μ between the tapered surfaces satisfies μ <tan θ. Pre-shear deformation holding device for the device.