JPH10168823A - Bridge fail preventing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To remove the limitation of mounting space and set a moving quantity from the viewpoint of moving portion of a superstructure by inserting a moving member to a guide member mounted under a connecting member, and mounting the upper part of the moving member on the lower part of the connecting member mounted on the lower surface of the superstructure and lower part to a stop member, respectively. SOLUTION: An upper part of a connecting member 2 formed of a pair of plate bodies is connected to the lower surface of a superstructure 6, and a cylindrical guide member 3 is mounted on the wall surface of a substructure 7 in the lower port thereof. The upward protruding part of a box-like moving member 4 inserted to the cavity part of the guide member 3 is rotatably connected between the lower parts of the connecting member 2, and a stop member 5 having a diameter larger than the guide member 3 is mounted on the lower protruding part. When the superstructure 6 beings to move in bridge falling direction, the moving member 4 is displaced so as to allow the movement to the moving quantity, and the movement is continued until the stop member 6 fixes the movement. Each member 2-5 is vertically situated, the limitation of mounting space of a bridge fall preventing device can be removed, and the moving quantity of the superstructure can be set.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for preventing a bridge from falling, and more particularly to a device for preventing a main girder as a superstructure from falling from an abutment as a substructure.

[0002]

2. Description of the Related Art The Hyogoken-Nanbu Earthquake caused severe damage to road bridges, and some bridges had to be dropped. On the other hand, the restoration specification required the installation of multiple anti-bridging devices that would not break even if a reaction force was applied. Specifically, it is the connection between superstructures, the connection between superstructures and substructures, and the installation of projections on substructures. In addition, it is disclosed that the device to be installed is configured to set a moving amount for the superstructure to start working after being moved to some extent and to have a structure capable of absorbing a shocking load.

[0003] The structure of the bridge-preventing device is relatively easy to connect to the superstructure and to install the projections on the substructure, but the connection between the superstructure and the substructure is limited by the mounting space as described later. Is often difficult.

[0004] The structure of the bridge-preventing device for connecting a superstructure and a substructure, which has been tried so far, is to connect the superstructure and the substructure with a chain or a PC cable so that the superstructure does not fall from the substructure. Those with a simple mechanism are common. For example, FIG. 8 shows a superstructure A placed on a substructure B via a shoe.
As shown in FIG. 9, the lower surface of the superstructure A and the lower surface of the substructure B are connected by a chain D via mounting members C and C attached to the wall surface of the substructure B. P via mounting members C, C mounted on the wall
It is a structure that is connected by a C cable. It should be noted that in the drawing, one of the facing superstructure and substructure is omitted.

[0005]

However, these structures have limitations on the mounting space due to the necessity of setting a movement amount for the superstructure to start working after being moved to some extent. For example, since an installation space is required to be long in the bridge axis direction, the installation of an overpass, an overpass, or the like becomes an obstacle to vehicles passing thereunder.

[0006]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and enables the installation of a moving amount for the superstructure to start working after being moved to some extent, and to absorb a shocking load. The proposed bridge prevention device is provided below.

First, the upper part of the connecting member having a vertical length is hinged to the lower surface of the superstructure via a mounting member, and a cylindrical guide member is positioned below the connecting member on the wall surface of the lower structure. So that a moving member having a length greater than the length of the guide member is inserted vertically into the guide member,
Provided is an apparatus for preventing a bridge from falling, wherein an upper protrusion of a moving member is hinged to a connecting member, and a stop member having a diameter larger than the diameter of the guide member is attached to the lower protrusion.

Second, the upper part of the connecting member having a vertical length is hinged to the lower surface of the superstructure via a mounting member, and a cylindrical guide member is positioned below the connecting member on the wall surface of the lower structure. So that a moving member having a length greater than the length of the guide member is inserted vertically into the guide member,
The upper protrusion of the moving member is hinged to the connecting member, a stop member having a diameter larger than the diameter of the guide member is attached to the lower protrusion, and a gap between the guide member and the moving member is filled with an elastic material. To provide a fall prevention device.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to FIGS.

The fall prevention device 1 comprises a connecting member 2, a guide member 3, a moving member 4, and a stop member 5, and connects an upper part 6 and a lower part 7. 8 is Kutsuto.

The connecting member 2 is composed of a pair of plate-like members 2a and 2b having a length in the vertical direction, and the upper part thereof is hinged to the lower surface of the superstructure 6 via a mounting member 9. Specifically, each of the mounting members 9 mounted by using the bolts 10 is hinged so as to be rotatable from the side using a shaft 11 and a nut 15.

The guide member 3 is formed into a cylindrical shape having a space 3b in which a moving member described later can move by a U-shaped cross-section plate-like body 3a and a mounting plate 12, so that the guide member 3 is located directly below the connecting member 2. The mounting plate 12 on the wall of the substructure 7
And are attached by bolts 13.

The moving member 4 is formed in a box shape and has a length greater than the length of the guide member. The moving member 4 is inserted into the gap 3 b of the guide member 3, and the upper projecting portion forms a pair of plate-like members forming the connecting member 2. A stop member 5 having a diameter larger than the diameter of the guide member is attached to the lower protruding portion, and is rotatably hinged between the lower portion of 2a and 2b using a shaft 14 and a nut 16.

These members are not limited to the above-described members. For example, the connecting members 2 do not need to form a pair, and the moving member 4 may have a columnar or plate shape. Good.

Here, the dimensions of the connecting member, the guide member, and the moving member are determined in consideration of the amount of movement for the superstructure to start working after being moved to some extent.

The space between the guide member 3 and the moving member 4 is filled with an elastic material such as synthetic resin or rubber. In the embodiment of the present invention, a two-pack type polybutadiene-based sealing material is filled.

In this way, a bridge prevention device is formed as a whole. Although not shown, a bridge prevention device and other bridge prevention devices according to the present invention are usually installed also on the lower construction side facing the other end side of the upper construction.

Next, FIG. 4 shows a bridge prevention process in the bridge prevention device according to the present invention, and FIG. 5 shows a state after operation.

In FIG. 4, (a) shows the state of the superstructure and the fall prevention device during normal times. In this state, when the superstructure 6 starts moving in the direction of the falling bridge, the superstructure 6 and the connecting member 2,
The action of the hinge connection between the connecting member 2 and the moving member 4 is as shown in FIG.
As shown in (2), the moving member 4 inserted through the connecting member 2 and the guide member 3 is displaced so as to allow the moving with respect to the moving amount. Then, when the movement of the superstructure 6 continues (c) and as shown in FIG. 5, the connecting member 2 and the moving member 4 are further displaced, and the movement is allowed until the movement is fixed by the stop member 5. These displacements are the movable amount.

During this series of operations, the elastic material filled in the gap between the guide member 3 and the moving member 4 suppresses the movement and absorbs energy.

FIG. 6 shows the relationship between the load and the amount of movement when the gap between the guide member and the moving member is filled with the elastic material and when the space is not filled with the elastic material. As shown in FIG. The measurement position of the degree of strain is a position 10 mm below the upper end of the guide member.

From these figures, it can be seen that the filling of the elastic material resists the movement of the superstructure from the initial stage.
It can be seen that the degree of strain of the guide member is reduced by filling even at the same load level. This has the effect of reducing the impact load and eliminating stress concentration.

[0023]

According to the first and second aspects, the upper part of the connecting member is connected to the lower surface of the superstructure, and a cylindrical guide member is mounted on the wall surface of the lower structure so as to be positioned below the connecting member. Since the moving member is inserted and the upper part of the moving member is connected to the connecting member, each member is located in the vertical direction, so that it is possible to eliminate the restriction on the mounting space when installing the fallen bridge prevention device.

Further, the connecting member and the upper surface are hingedly connected to each other, and the connecting member and the moving member are hinged to each other, and the moving member is inserted through a guide member having a gap in which the moving member can move, thereby displacing the connecting member and the moving member. Is the movable amount of the superstructure.

Further, the mounting of the stop member below the moving member is also effective in restricting the movement in the direction perpendicular to the bridge axis and in the upward direction.

According to the second aspect of the present invention, since the elastic material is filled in the gap of the guide member, an impact load applied to the bridge falling prevention device is reduced.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a bridge prevention device according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG. 2;

FIG. 4 is a conceptual diagram of a bridge prevention process of the bridge prevention device according to the present invention.

FIG. 5 is an explanatory view showing a state after the fall prevention device according to the present invention is operated.

FIG. 6 is a diagram showing a relationship between a moving amount and a load when a gap between a guide member and a moving member is filled with an elastic material and when the space is not filled, in the bridge falling prevention device according to the present invention.

FIG. 7 is a diagram showing a change in the degree of strain at the same load level when the gap between the guide member and the moving member is filled with the elastic material and when the gap is not filled in the bridge fall prevention device according to the present invention. is there.

FIG. 8 is an explanatory view showing a conventional bridge prevention device in which a superstructure and a substructure are connected.

FIG. 9 is another explanatory view showing a conventional bridge-fall prevention device in which a superstructure and a substructure are connected.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Bridge fall prevention device 2 Connecting member 3 Guide member 3b Air gap 4 Moving member 5 Stop member 6 Superstructure 7 Lower construction 8 Shoes 9 Mounting member 10 Bolt 11 Shaft 12 Mounting plate 13 Bolt 14 Shaft 15 Nut 16 Nut

Claims (2)

[Claims] An upper part of a connecting member having a length in the vertical direction is hinged to a lower surface of a superstructure through a mounting member so that a cylindrical guide member is positioned below the connecting member on a wall surface of the lower structure. A movable member having a length larger than the length of the guide member is inserted vertically into the mounting and guiding member, the upper projecting portion of the moving member is hinged to the connecting member, and the lower projecting portion is larger than the diameter of the guide member. A fall prevention device comprising a stop member having a diameter of at least one. 2. An upper part of a connecting member having a vertical length is hingedly connected to a lower surface of an upper part via a mounting member, and a cylindrical guide member is positioned below the connecting member on a wall surface of the lower part. A moving member having a length greater than the length of the guide member is inserted vertically into the mounting and guiding member, the upper projecting portion of the moving member is hinged to the connecting member, and the lower projecting portion is larger than the diameter of the guiding member. A fall member attached to the guide member and the moving member, wherein a gap between the guide member and the moving member is filled with an elastic material.