JPH11315510A - Connecting bridge fall prevention device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a connecting bridge fall prevention device capable of solving the deflection of a tendon, thinning a safety stopper and reducing the weight thereof. SOLUTION: A connecting bridge fall prevention device 10 is prevented a fall of bridge by connecting bridge girders to each other. The connecting bridge fall prevention device 10 is located at the left side from the viewpoint of the side. A device pulling a coil spring 12 out of the normal connecting bridge fall prevention device 10 is located at the right side. It is mounted to horizontal girders C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connecting type fall prevention device which is particularly suitable for a multi-span continuous girder.

[0002]

2. Description of the Related Art In recent years, in the field of bridges such as road bridges and railway bridges, bridge girder has become continuous due to economical efficiency, running performance and safety.
It is getting longer. In particular, since the Great Hanshin Earthquake, safety has been emphasized, and the continuation of bridge girder has become remarkable. This is because, if one bridge girder is covered over multiple spans, even if both ends of the bridge girder are dropped, there is a high possibility that the bridge girder will be supported by the remaining pier.

In order to further enhance safety, it is obligatory to install a bridge prevention device in continuous girder from the viewpoint of bridge prevention (for example, "Data on Seismic Design of Road Bridge" edited by Japan Road Association).

Conventionally, various devices have been developed and provided as such a bridge prevention device. One of them is a connection-type bridge prevention device that connects adjacent bridge girders.

[0005] By the way, when the bridge girder becomes longer, the "girder length" of the bridge girder on the abutment or pier becomes longer. According to "documentation on Seismic Design of Highway Bridges", "digit takes length" is because is calculated based on the length of the bridge girder (S _E: the article 2.6.1).

Accordingly, the maximum design movement (= the amount of deformation of the elastic bearing) in proportion to the "girder length" increases (S
_F : The above document 2.6.3).

[0007] Therefore, it was necessary to lengthen the stroke of the connection type fall prevention device.

[0008]

However, if the stroke of the articulated bridge prevention device according to the prior art is lengthened as it is, the following problems arise.

When the spring provided at the end of the tendon such as PC steel is adjusted to the stroke length, the spring must be softened, and as a result, the tendon is bent.

In addition, if the stroke is lengthened, the contact height (height in a state where the spring is completely contracted = wire diameter × number of turns) increases, so that the safety stopper which starts contracting before the contact height must be thickened. did not become.

Further, as the length of the spring and the safety stopper increases, the weight increases in proportion thereto.

In particular, these problems are greater in a continuous girder between multiple diameters.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to eliminate the bending of the tendon, to reduce the thickness of the safety stopper, and to reduce the weight. It is in providing a fall prevention device.

[0014]

The gist of the present invention resides in that an end of a connecting member suspended between a bridge girder and a bridge girder or abutment adjacent thereto is fixed to the bridge girder or abutment to prevent dropping of a bridge. A tubular body positioned at an end of the connecting member and inserted through the connecting member, and a biasing member for biasing the tubular body toward an end of the connecting member. Means, a fixture fixed to an end of the connecting member, and a connection / rupture member that restrains relative movement between the connecting member and the cylindrical body and breaks when a predetermined stress is generated. It is in the feature of the connection type fall prevention device. The gist of the invention according to claim 2 resides in the connection-type fall prevention device according to claim 1, wherein the cylinder is urged via a support plate. The gist of the invention described in claim 3 is that the cylinder is provided with a flange, and the urging means is interposed between the flange and the pier or the abutment. In the articulated fall prevention device. The gist of the invention according to claim 4 resides in a connection type fall prevention device according to claim 1 or 3, wherein a supporting plate is provided between the urging means and the bridge girder or the abutment. The gist of the invention according to claim 5 is a connection type fall prevention device for fixing an end portion of a connecting material suspended between a bridge girder and an adjacent bridge girder or abutment to the bridge girder or abutment to prevent a bridge from falling. A cylindrical member positioned at an end of the connecting member and inserted through the connecting member, a fixing member fixed to an end of the connecting member, and restricting relative movement between the connecting member and the cylindrical member. A connection / rupture member that breaks when a predetermined stress is generated. The gist of the invention according to claim 6 is that the fixing tool is a nut and a washer, and the connecting / breaking member is inserted through the cylinder and screwed to a side surface of the washer. The present invention resides in a connecting type fall prevention device according to any one of claims 1 to 5. The gist of the invention according to claim 7 is that the connection / rupture member penetrates the tubular body and locks the washer. It is in the articulated bridge prevention device. The gist of the invention according to claim 8 is that the cushioning material is interposed on the bridge girder or the abutment side of the supporting plate, wherein the connection type fall prevention device according to any one of claims 1 to 7 is provided. Exists. The gist of the invention according to claim 9 is a connection type fall prevention device for fixing a bridge girder and an end portion of a connecting material suspended between the bridge girder and an abutment to the bridge girder or the abutment to prevent a bridge from falling. A cylindrical body that is inserted into the connecting member at an end of the connecting member,
There is provided a connection-type bridge prevention device, comprising: a fixing member fixed to an end portion of the connection member; and a restraining member for restraining relative movement between the connection member and the cylindrical body. Claim 10
The gist of the present invention resides in a connection-type fall prevention device according to any one of claims 1 to 9, wherein a cap is attached to an end of the cylindrical body. Claim 1
The gist of the invention described in (1) resides in the connection type fall prevention device according to any one of claims 1 to 10, wherein the support plate is covered by a casing.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings. As shown in FIG. 1, a connection-type bridge prevention device 10 according to the present embodiment is to prevent a bridge from being dropped by connecting bridge girders. It is a connection type fall prevention device 10 according to the embodiment. On the right side, the coil spring 12 has been removed from the normal connection-type fall prevention device 10. In the figure, reference symbol C denotes a horizontal beam, which is attached to the horizontal beam in the present embodiment. 1 to 4 is an embodiment of the invention described in claims 1 and 2. FIG.

[0016] The support tube 11 (cylindrical body) covering the end of the PC steel stranded wire L (connecting material), the PC steel stranded wire L, and the support tube 11 are urged toward the end of the PC steel stranded wire L. A coil spring 12 (biasing means), a support plate 13 interposed between the support tube 11 and the coil spring 12,
It comprises a W nut 14a and a washer 14b (fixing tool) screwed to the end of the PC steel strand L, and a knock-off bolt 15 (connection / breaking member) for connecting the support pipe 11 and the PC strand L. ing.

The PC steel stranded wire L is provided with sleeves Ls having male threads cut at both ends, so that the W nut 14a can be screwed thereon, and the remainder is coated with polyethylene.

The support tube 11 is opened at both ends, and has a flange 11a formed on the outer surface thereof, and is in contact with the support plate 13. The diameter of the flange 11a is the same as that of the support plate 13. A rust prevention cap 16 is attached to an end of the support tube 11.

The supporting plate 13 is a disc-shaped steel plate having a hole formed at the center thereof through which a PC stranded wire L is inserted, and having an outer surface coated with rust prevention. The urging force from the coil spring 12 is transmitted to the support tube 11.

The coil spring 12 is interposed between the support plate 13 and the cross beam.

The knock-off bolt 15 restrains the relative movement between the fixture and the support tube 11 and breaks when a predetermined stress is generated.

The washer 14b is rust-proof coated, and a female screw is cut radially on a side surface thereof, and a knock-off bolt 15 is screwed.

Further, a safety stopper 17 (buffer) is interposed on the bridge girder side of the support plate 13. The safety stopper 17 is made of chloroprene rubber and has a donut shape in which a hole into which the end of the coil spring 12 can be inserted is opened at the center.

The support plate 13 and the safety stopper are covered by a casing.

Next, the operation of the articulated bridge prevention device 10 will be described.

The state shown in FIG. 2 is a stationary state (no vibration).

When vibration occurs and a relative displacement occurs between the bridge girders, the spring retracts as shown in FIG. 3 and abuts on the flange 11a of the support pipe 11 with the safety stopper. Responsible for small / medium-scale earthquakes, live loads, temperature expansion / contraction, etc. with the stroke until it comes into contact with the safety stopper. In other words, the stroke determined by the length of the coil spring 12 and the safety stopper is reduced by a small
The length should be long enough to absorb the amplitude due to a medium-scale earthquake or the like.

When a large-scale earthquake occurs, the relative displacement between the bridge girders increases, and the PC steel is further pulled rightward from the state in which the flange 11a of the support pipe 11 is in contact with the safety stopper shown in FIG. As shown in 4,
The rupture stress is generated in the knock-off bolt 15, and the knock-off bolt 15 is ruptured, and the washer 14b contacts the safety stopper via the support plate 13. It is desirable that such a state occurs before the design maximum movement amount S _F described in the related art is reached. Usually, because it is designed to be larger than the allowable deformation amount designed maximum travel S _F of the elastic bearing, also not destroyed elastic support.

[0029] The articulated bridge prevention device 10 according to the embodiment.
Is configured as described above, and has the following effects.

Of the maximum design travel, only the temperature change, live load, and travel due to small and medium scale earthquakes are handled by springs, and the travel due to a large earthquake up to the design maximum travel is knock-off bolt 15. This is achieved by ensuring the movement of the tendon end due to the breakage of the support tube 11 or the breakage of the support tube 11.
As a result, the present invention can be applied to continuous girders without increasing the length of the spring.

The articulated bridge prevention device 1 according to the present embodiment.
According to 0, it is not necessary to reduce the coefficient of the spring, so that the bending of the tendon can be eliminated. Also, the safety stopper can be made thinner and the weight can be made smaller.

Also, by changing the length of the support tube 11, it is possible to cope with the design maximum movement amount S _F , and since it is not necessary to change the length of the coil spring 12, the PC steel stranded wire L is bent. I have no choice.

Further, the operation timing can be arbitrarily set only by changing the strength and thickness of the knock-off bolt 15.

Further, the length of the sleeve Ls can be shortened.

Further, it is possible to assemble and carry in the factory, and therefore, it is easy to install the bridge girder. In such a case, only the opposite side of the PC stranded wire L may be assembled.

Further, a cradle required for the articulated bridge-preventing device 10 according to the prior art is not required.

In addition, vibrations due to small / medium-scale earthquakes can be absorbed by the coil spring 12 and the knock-off bolt 15 can be prevented from being broken, so that maintenance is easy. The knock-off bolt 1
Even when 5 is broken, only the knock-off bolt 15 needs to be replaced, so that repair can be performed simply and inexpensively.

In the present embodiment, the bridge girders are connected to each other. However, the present invention is not limited to this, and the bridge girders can be applied to a bridge girder or the like suitable for applying the present invention.

In the above embodiment, the support tube 11
Although it is provided on the outside of the flange 11a provided in the above, it may be provided on the inside.

Further, in the above-mentioned portable device, it is installed directly on the horizontal girder, but it can also be installed on the side of the main girder using a bracket.

Although the knock-off bolt 15 is used as the connecting / breaking member, a rod-shaped hooking member or the like can be made suitable for practicing the present invention. In such a case, the washer may be hooked on the side of the side beam.

Further, the connection type fall prevention device 20 shown in FIG.
As described above, the cylindrical body is provided with a ring-shaped locking flange 21 extending radially outward, and a biasing means 22 may be interposed between the locking flange 21 and the pier or abutment.
FIGS. 6 and 7 show the operation of such an articulated bridge prevention device. Note that the locking flange may be discontinuous in the radial direction, and may have any shape as long as the urging means can be locked. The connection type fall prevention device 20 shown in FIGS. 5 to 7 is an embodiment of the invention described in claims 3 and 4.

As shown in FIG. 8, the biasing means may be provided in the other connection-type bridge prevention device (prior art) P, and may not be used in the connection-type bridge prevention device 30 according to the present invention. . The connection type fall prevention device 30 is an embodiment of the invention according to any one of claims 5 to 8.

Further, the connection type fall prevention device 40 shown in FIG.
As a result, the knock-off bolt is omitted, and the cylindrical bodies 43, 44, 4
5 itself can be destroyed so that it can cope with large amplitudes. FIG. 9 shows a state in which the connection type fall prevention device 40 is crushed. In the drawing, the symbol is PC steel strand L
Bolt 41 (restraining member) for restraining relative movement between the cylinder and the cylinder, and is screwed to the washer 42. Restraint bolt 4
Reference numeral 1 denotes a steel material and diameter that does not break even when vibrated by a large-scale earthquake, and the cylindrical body is destroyed first. Examples of the shape of such a cylindrical body are shown in FIGS. The cylindrical body 43 shown in FIG. 10 has a bellows shape and is easily crushed. Further, the cylindrical body 44 shown in FIG. 11 swells outward in the radial direction and is easily crushed. In addition, the cylindrical body 45 shown in FIG. 12 is provided with slits on the side surface along the longitudinal direction at equal intervals in the circumferential direction. 10 to 12, the right side is a side view of the cylindrical bodies 43, 44, 45, and the left side is the cylindrical bodies 43, 44, 4.
5 is a front view of FIG. 9 to 12 is an embodiment of the invention according to claims 9 to 11.

The number, position, shape, and the like of the above-mentioned constituent members are not limited to the above-described embodiment, but can be set to a number, position, shape, and the like suitable for carrying out the present invention. In the drawings, the same components are denoted by the same reference numerals.

[0046]

Since the present invention is configured as described above, the following effects can be obtained. Of the maximum design travel, only spring movement responds to temperature changes, live loads, and travel due to small and medium-scale earthquakes, and knock-off bolts are broken or supported for travel due to large earthquakes up to the design maximum travel. This will be dealt with by ensuring the movement of the tendon end due to the tube breaking. As a result, without increasing the length of the spring,
It can be applied to continuous digits. Therefore, according to the present invention, it is not necessary to reduce the coefficient of the spring, and the bending of the tendon can be eliminated. Also, the safety stopper can be made thinner and the weight can be made smaller.

[Brief description of the drawings]

FIG. 1 is a vertical cross-sectional view showing a state in which a connecting type bridge prevention device according to an embodiment of the present invention is attached to a cross beam.

FIG. 2 is a longitudinal sectional view showing the operation of the articulated type fall prevention device shown in FIG.

FIG. 3 is a longitudinal sectional view showing the operation of the articulated type fall prevention device shown in FIG. 1;

FIG. 4 is a longitudinal sectional view showing an operation of the articulated bridge prevention device shown in FIG. 1;

FIG. 5 is a longitudinal sectional view of a connection type fall prevention device according to another embodiment of the present invention.

FIG. 6 is a view showing the operation of the articulated dropping prevention device shown in FIG. 5;

FIG. 7 is a view showing the operation of the articulated type fall prevention device shown in FIG. 5;

FIG. 8 is a longitudinal sectional view of a connection type fall prevention device according to another embodiment of the present invention.

FIG. 9 is a longitudinal sectional view of a connection type fall prevention device according to another embodiment of the present invention.

FIG. 10 is a view showing a modified example of the cylindrical body of the connection-type bridge prevention device of the present invention.

FIG. 11 is a view showing a modified example of the cylindrical body of the connection type fall prevention device of the present invention.

FIG. 12 is a view showing a modified example of the cylinder of the articulated type fall prevention device of the present invention.

[Explanation of symbols]

 C Cross girder L PC steel strand (connection material) Ls sleeve P Connection type bridge prevention device (conventional technology) 10 Connection type bridge prevention device 11 Support pipe (tubular body) 11a Flange 12 Coil spring (biasing means) 13 Pressure plate 14a, 14b W nut and washer (fixing tool) 15 Knock-off bolt (connecting / breaking member) 16 Rust prevention cap 17 Safety stopper (buffer material) 20 Linkage type bridge prevention device 21 Locking flange 22 Biasing means 30 Linkage type bridge prevention Apparatus 40 Connecting type fall prevention device 41 Restraint bolt 42 Washer 43,44,45 Cylindrical body 45a Slit

Claims (11)

[Claims] 1. A connection type bridge prevention device for fixing an end of a connecting member suspended between a bridge girder and a bridge girder or abutment adjacent thereto to the bridge girder or abutment to prevent the bridge from falling. A tubular body positioned at an end portion and inserted through the connecting member; an urging means for urging the tubular body toward an end of the connecting member; and a fixed member fixed to an end portion of the connecting member. And a connection / rupture member that restrains relative movement between the connecting member and the cylindrical body and breaks when a predetermined stress is generated. 2. The bridge-type bridge prevention device according to claim 1, wherein the cylinder is urged via a support plate. 3. The connection type bridge prevention device according to claim 1, wherein a flange is provided on the cylindrical body, and the urging means is interposed between the flange and the pier or the abutment. apparatus. 4. The connection type fall prevention device according to claim 1, wherein a support plate is provided between the urging means and the bridge girder or the abutment. 5. A connection type fall prevention device for fixing an end of a connecting member suspended between a bridge girder and a bridge girder or abutment adjacent thereto to the bridge girder or abutment to prevent a bridge from falling off, comprising: A tubular member positioned at an end portion and inserted through the connecting member; a fixing member fixed to an end portion of the connecting member; and restraining relative movement between the connecting member and the cylindrical member, and a predetermined stress is reduced. A connection-type bridge prevention device having a connection / break member that breaks when it occurs. 6. The fixing device according to claim 1, wherein the fixing member is a nut and a washer, and the connecting / breaking member is inserted through the cylindrical body and is screwed to a side surface of the washer. 6. The connection type fall prevention device according to any one of 1 to 5. 7. The connection-type bridge prevention device according to claim 1, wherein the connection / rupture member penetrates the cylindrical body and locks the washer. . 8. The connection type bridge prevention device according to claim 1, wherein a cushioning material is interposed on the bridge girder or the abutment side of the support plate. 9. A connection type bridge prevention device for fixing an end of a connecting member suspended between a bridge girder and a bridge girder or abutment adjacent to the bridge girder to the bridge girder or the abutment, thereby preventing a bridge from being dropped. A tubular body that is inserted at the end side of the connecting member and is fixed to an end of the connecting member; and a restraint member that restrains relative movement between the connecting member and the tubular body. An articulated bridge-prevention device characterized by having: 10. The connection-type fall prevention device according to claim 1, wherein a cap is attached to an end of the cylindrical body. 11. The connection-type fall prevention device according to claim 1, wherein the support plate is covered with a casing.