JP2023007956A - Fitting structure of bridge-suspending cable - Google Patents

Abstract

To provide a fitting structure of a bridge-suspending cable which can be easily installed with a conventional simple structure.SOLUTION: In a cable 10 for a power or a communication, linked to a road bridge 2, an excess length part 11 bent like a lateral 8-shape in an end part of a first bridge girder 3. Upper end parts 11a and 11b of the excess length part 11 are supported by excess part holding members 12 and 12. Each excess part holding member 12 includes: a cylinder member 15 inserted into the cable 10; and a plurality of connection ropes 16 and 16 for coupling a part of the cylinder member 15 to a support member 14. An annular part 18a on a tip side of a release liner member 18 as a holding release mechanism is engaged to the connection ropes 16 and 16 of each excess part holding member 12, and the annular part on a base side is coupled to a lateral girder 20 on a second bridge girder 4 side. When displacement exceeding a reference value occurs between the first bridge girder 3 and the second bridge girder, a tension occurs in the release liner member 18 to cut each connection rope 16, and holding of the excess part 11 by each excess part holding member 12 is released.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to an installation structure for a power or communication cable that is attached to a bridge.

2. Description of the Related Art Conventionally, as a structure for mounting power or communication cables on a bridge, there has been known a structure configured to reduce the influence of the displacement of the constituent members of the bridge. As such a cable mounting structure, conventionally, a cable is curved in a mountain shape to form surplus length portions near two adjacent bridge girder ends, and the bridge girder end portions of each surplus length portion are opposed to each other. A proposal has been made to connect to an arm member extending from the end of a bridge girder (see Patent Document 1).

In this bridge-attached cable mounting structure, the tip portions of the two arm members are fitted so as to be guided by guide members provided on the opposing bridge girder end sides. Also, a displacement reduction device is installed near the tip of one of the arm members to reduce the displacement of the connecting portion of the excess length of the cable at the end of the other bridge girder to half the displacement of the arm member. .

When a displacement occurs between adjacent bridge girders, the connecting portion of the cable to the arm member moves in the direction in which the arm member is guided, and the movement distance of the two connecting portions is equalized by the displacement reduction device. . Thereby, the two surplus length portions of the cable are configured to be expanded and contracted evenly.

JP-A-02-250612

However, the conventional bridge-mounted cable mounting structure includes an arm member, a connecting member that connects the cable to the arm member, a guide member that guides the arm member, and a displacement reducing device, so the number of parts is relatively small. In addition, there is the inconvenience that installation takes time and effort. In addition, since a relatively large space is required for installation of the arm member, the guide member, and the displacement reduction device, there is an inconvenience that installation may not be possible depending on the structure of the bridge. Moreover, since the displacement reducing device includes mechanical elements such as a rack and a pinion, it is troublesome in maintenance and relatively low in durability.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a bridge-attached cable mounting structure that can be easily installed with a relatively simple configuration, can be installed in a relatively narrow space, and has high durability.

In order to solve the above problems, the bridge-attached cable mounting structure of the present invention is a mounting structure for a communication or power cable that is stretched between a first member and a second member of a bridge,
an extra length portion provided near the end of the first member or the second member of the cable;
a surplus length portion holding member that holds the surplus length portion of the cable at a holding position set in the first member or the second member;
When a relative displacement exceeding a reference value occurs between the first member and the second member, the surplus length portion of the cable can be extended by releasing the holding of the surplus length portion of the cable by the surplus length portion holding member. It is characterized by comprising a holding release mechanism for holding.

According to the above configuration, the extra length part is positioned near the end of the first member or the second member in the cable attached to the bridge by spanning between the first member and the second member. It is formed. Here, the extra length portion may be formed in one of the first member and the second member, or may be formed in both the first member and the second member, and the number of extra length portions is particularly limited. not. The first member and the second member of the bridge are members that constitute the bridge, and correspond to members that are mutually displaced due to various causes such as an earthquake, vehicle load, and wind load. For example, the first member and the second member correspond to a bridge girder and a bridge girder adjacent to each other. Further, for example, the first member and the second member correspond to a bridge girder and abutment adjacent to each other. The above cables are cables for communication or electric power that are attached to bridges, and correspond to those using conductors such as copper and aluminum, and those using optical fibers. The surplus length portion of the cable is held at the holding position set in the first member or the second member by the surplus length portion holding member. The holding position is set to the member on the side where the extra length portion is formed. For example, when the extra length portion is formed near the end of the first member, the holding position is set to the first member. . Here, when the relative displacement exceeding the reference value occurs between the first member and the second member, the retention of the excess length portion of the cable by the excess length portion holding member is released by the retention release mechanism. As a result, the excess length of the cable can be extended. As a result, the cable can follow the relative displacement of the first member and the second member, thereby reducing the influence on the cable and effectively preventing problems such as disconnection or disconnection of the cable. The structure for mounting the bridge-attached cable having the above-described configuration is relatively simple with the excess length portion holding member for holding the extra length portion and the holding release mechanism, so that it can be easily installed and installed in a relatively narrow space. . Moreover, since it does not include mechanical elements such as racks and pinions, it requires little maintenance and has high durability.

In one embodiment of the bridge-attached cable mounting structure, the excess length portion holding member includes a linear member that connects the excess length portion of the cable to the first member or the second member,
The holding release mechanism includes a tension member that exerts a tensile force when a relative displacement exceeding a reference value occurs between the first member and the second member, and the excess length portion holding member due to the tensile force of the tension member. and a cutting member for cutting the linear member.

According to the above embodiment, the excess length portion holding member includes the linear member, and the excess length portion of the cable is connected to the first member or the second member by the linear member. The linear member may be connected to the first member or the second member either directly or indirectly via another member. Along with this, the holding release mechanism includes a tension member and a cutting member, and when a relative displacement exceeding a reference value occurs between the first member and the second member, the tensile force generated in the tension member causes the cutting member to move to the above position. The linear member of the extra length holding member is cut. When the linear member of the extra length holding member is cut by the cutting member, the excess length of the cable is disconnected from the first member or the second member, so that the extra length can be extended. As a result, the cable can follow the relative displacement between the first member and the second member, thereby preventing breakage or cutting of the cable.

In one embodiment of the bridge-attached cable mounting structure, the tensile member of the holding release mechanism is formed of a linear member having a higher strength than the linear member of the excess length portion holding member,
The cutting member of the holding release mechanism is provided at the tip of the linear member as the tension member, and is formed by an annular portion that engages with the linear member of the excess length holding member.

According to the above embodiment, the holding release mechanism is formed by the linear member as the tension member and the annular portion provided at the tip of the linear member. When a relative displacement exceeding a reference value occurs between the first member and the second member of the bridge, a tensile force acts on the annular portion due to the tension generated in the linear member as the tension member. Here, since the linear member as the tension member of the retention release mechanism has a higher strength than the linear member of the extra length holding member, the linear member of the excess length holding member is cut by the annular portion. As a result, the retention of the surplus length portion of the cable by the surplus length portion holding member is effectively released. Here, the annular portion as the cutting member of the holding release mechanism may be formed by bending the tip of the linear member as the tension member into an annular shape and fixing it in the middle of the linear member. That is, the pulling member and the cutting member of the holding release mechanism may be integrally formed by a linear member.

In one embodiment of the bridge-attached cable mounting structure, the tension member of the holding release mechanism is formed of a linear member,
The cutting member of the holding release mechanism is formed of a cutting blade that is driven by the tensile force of the linear member as the pulling member to cut the linear member of the excess length portion holding member.

According to the above embodiment, the holding release mechanism is formed including the linear member as the tension member and the cutting blade driven by the tensile force acting on the linear member. When a relative displacement exceeding a reference value occurs between the first member and the second member of the bridge, the tension generated in the linear member as the tension member drives the cutting blade, and the cutting blade drives the extra length holding member. of linear members are cut. As a result, the retention of the excess length portion of the cable by the excess length portion holding member is effectively released.

In one embodiment of the bridge-attached cable mounting structure, the excess length portion holding member includes an engaging fitting that engages with the first member or the second member,
When the holding release mechanism generates a relative displacement exceeding a reference value between the first member and the second member, a tensile force acts. A tension member is included to disengage the member.

According to the above embodiment, the engaging metal fittings of the surplus portion holding member are engaged with the first member or the second member to hold the surplus portion of the cable at the holding position of the first member or the second member. Here, the engaging fitting may be directly engaged with the first member or the second member, or indirectly engaged via another member provided on the first member or the second member. may The retention release mechanism includes a tension member, and a tensile force acts on the tension member of the retention release mechanism when relative displacement between the first member and the second member exceeds a reference value. The engagement of the engaging fitting with the first member or the second member is released by the pulling force of the pulling member of the holding release mechanism. As a result, the retention of the excess length portion of the cable by the excess length portion holding member is effectively released.

In one embodiment of the bridge-attached cable mounting structure, the excess length portion holding member includes a magnet that attracts the excess length portion of the cable to the first member or the second member,
In the holding release mechanism, when a relative displacement exceeding a reference value occurs between the first member and the second member, a tensile force acts, and the tensile force acts on the magnet to the first member or the second member. includes a tension member that releases the adsorption of the

According to the above embodiment, the magnet of the extra length holding member is attracted to the first member or the second member to hold the excess length of the cable at the holding position of the first member or the second member. Here, the magnet may be directly attracted to the first member or the second member, or may be indirectly attracted to another member provided on the first member or the second member. The retention release mechanism includes a tension member, and a tensile force acts on the tension member of the retention release mechanism when relative displacement between the first member and the second member exceeds a reference value. The attraction of the magnet to the first member or the second member is released by the pulling force of the pulling member of the holding release mechanism. As a result, the retention of the excess length portion of the cable by the excess length portion holding member is effectively released.

In one embodiment of the bridge-attached cable mounting structure, the tension member of the retention release mechanism is a member, of the first member and the second member, having an extra length portion that is released from retention by the retention release mechanism. connected to a different member.

According to the above embodiment, the holding and releasing mechanism for the extra length portion arranged on one of the first member and the second member is such that the tension member of this holding and releasing mechanism is connected to the other member. , a tensile force acts on the tensile member as the relative displacement between the first member and the second member exceeds a reference value. Therefore, the holding release mechanism can reliably release the holding of the surplus portion of the cable by the surplus portion holding member.

In one embodiment of the bridge-attached cable mounting structure, the surplus length portion of the cable at the holding position is bent in a mountain shape.

According to the above-described embodiment, the surplus portion of the cable can be easily formed by forming the shape of the surplus portion in a mountain shape.

In one embodiment of the bridge-attached cable mounting structure, the surplus length portion of the cable at the holding position is bent in a figure-of-eight shape.

According to the above-described embodiment, by forming the surplus portion of the cable into a figure 8 shape, it is possible to prevent twisting of the cable when the surplus portion is extended. can effectively prevent damage caused by

In one embodiment of the bridge-attached cable mounting structure, the surplus length portion of the cable at the holding position is formed of two wound portions that are wound on opposite sides.

According to the above-described embodiment, the excess length of the cable is formed by two wound portions that are wound on opposite sides of each other, so that twisting of the cable when these two excess lengths are extended can be prevented. can be prevented. Therefore, it is possible to effectively prevent damage caused by torsion, such as wire breakage. Here, it is preferable that the wound portion of the cable is formed near the end of the first member and near the end of the second member.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic diagram showing a bridge provided with a bridge-attached cable mounting structure according to a first embodiment of the present invention; FIG. 4 is a side view showing a first extra length holding member in the bridge-attached cable mounting structure of the first embodiment; FIG. 4 is a schematic diagram showing the mounting structure of the bridge-attached cable of the first embodiment when an earthquake occurs. FIG. 10 is a cross-sectional view showing a surplus length portion holding member and a holding release mechanism in the bridge-attached cable mounting structure of the second embodiment; FIG. 11 is a plan view showing a surplus length portion holding member and a holding releasing mechanism in the bridge-attached cable mounting structure of the second embodiment; FIG. 10 is a cross-sectional view showing an extra length portion holding member and a holding releasing mechanism in the bridge-attached cable mounting structure of the second embodiment when an earthquake occurs. FIG. 11 is a plan view showing a surplus length portion holding member and a holding releasing mechanism in the bridge-attached cable mounting structure of the third embodiment; FIG. 11 is a side view showing a surplus length portion holding member and a holding releasing mechanism in the bridge-attached cable mounting structure of the third embodiment; FIG. 11 is a plan view showing the surplus length portion holding member and the holding release mechanism in the attachment structure of the bridge attached cable of the third embodiment when an earthquake occurs. FIG. 11 is a side view showing an extra length holding member and a holding release mechanism in the bridge-attached cable mounting structure of the fourth embodiment; FIG. 11 is a side view showing the surplus length portion holding member and the holding release mechanism in the attachment structure of the bridge attached cable of the fourth embodiment when an earthquake occurs. FIG. 14 is a side view showing an extra length holding member and a holding release mechanism in the bridge-attached cable mounting structure of the fifth embodiment. FIG. 14 is a side view showing the surplus length portion holding member and the holding release mechanism in the bridge attachment cable mounting structure of the fifth embodiment when an earthquake occurs. FIG. 11 is a schematic diagram showing a bridge provided with a bridge-attached cable mounting structure according to a sixth embodiment; FIG. 11 is a schematic diagram showing a bridge provided with a bridge-attached cable mounting structure according to a seventh embodiment;

The present invention will be described in detail below with reference to the illustrated embodiments.

FIG. 1 is a schematic diagram showing a portion of a bridge provided with a bridge-attached cable mounting structure according to a first embodiment of the present invention. This bridge-attached cable mounting structure 1 is installed between a first bridge girder 3 as a first member and a second bridge girder 4 as a second member of a road bridge 2 as a bridge. This road bridge 2 is a girder bridge, and adjacent ends of a first bridge girder 3 and a second bridge girder 4 are supported by bearings 6 and 7 installed at the upper ends of bridge piers 5 .

A power or communication cable 10 is attached to the superstructure of the road bridge 2 while being supported by cable racks 8 and 9 installed on bridge girders 3 and 4 . Here, the material of the cable 10 is not particularly limited as long as it is a cable used for electric power or communication. The cable 10 corresponds to, for example, a cable using a conductor such as copper or aluminum, or a cable using an optical fiber. Also, the number of conductors and optical fibers housed in the cable 10 is not limited. The mounting structure 1 of the bridge-attached cable of this embodiment prevents the disconnection of the cable 10 when displacement occurs between the first bridge girder 3 and the second bridge girder 4. It is installed to follow the displacement of the bridge girder 4 of 2.

The mounting structure 1 of the bridge-attached cable of the first embodiment includes a surplus length portion 11 of the cable provided at the end portion of the first bridge girder 3, and the surplus length portion 11 is attached to the end portion of the first bridge girder 3. Two extra length portion holding members 12, 12 held at the set holding position, and two release lines functioning as a holding release mechanism for releasing the holding of the excess length portion 11 by the extra length portion holding members 12, 12. It is configured including shaped members 18 , 18 . The surplus portion 11 of the cable is formed by bending the cable 10 into a horizontal figure-eight shape.

The surplus length 11 of the cable in the mounting structure 1 for the bridge attached cable is set to a length larger than the maximum value of displacement that can be assumed between the first bridge girder 3 and the second bridge girder 4 when extended. It is That is, the displacement between the first bridge girder 3 and the second bridge girder 4 that can be assumed during an earthquake, for example, is lower than when the cable 10 is arranged in a straight line between the first bridge girder 3 and the second bridge girder 4. A portion corresponding to a length obtained by adding a marginal length to the maximum value is set as a marginal length portion 11 . The extra length portion 11 has its lower end portion disposed on the cable rack 8, and its two upper end portions 11a and 11b of the horizontal figure 8 are supported by two extra length portion holding members 12 and 12, respectively. there is

FIG. 2 is a schematic diagram showing an enlarged surplus portion holding member 12 that supports one upper end portion 11a of the surplus portion 11. As shown in FIG. The excess length holding member 12 is connected to a bar-shaped metal support member 14 fixed to the first bridge girder 3 . Note that the shape and material of the support member 14 are not particularly limited as long as the excess length portion holding member 12 can be connected so as to be able to support the extra length portion 11 . The surplus portion holding member 12 includes a flexible tubular member 15 through which the cable 10 is inserted, and a plurality of linear members that wind and connect the covering portion of the cable 10 with the tubular member 15 and the support member 14 . It has connecting cords 16, 16 as members. The tubular member 15 can be formed of, for example, a corrugated rigid polyethylene tube. The connecting string 16 can be formed of, for example, a braid made of vinylon.

As shown in FIG. 2 , a plurality of connecting cords 16 , 16 are engaged with the distal end of a releasing linear member 18 in the extra length holding member 12 . The release linear member 18 is made of, for example, a stainless steel wire, and is eye-processed at both ends to form an annular portion. An annular portion 18a on the distal end side of the releasing linear member 18 is engaged with a plurality of connecting cords 16, 16 of the excess length portion holding member 12 in a chain shape. Further, the base end side of the releasing linear member 18 is connected to the second bridge girder 4, which is a member different from the member on which the excess length portion 11 is installed. The base end side of the releasing linear member 18 is connected to a connecting hole provided in the horizontal beam 20 on the side of the second bridge girder 4 by engaging an annular portion thereof. This releasing linear member 18 has a higher strength than the connecting string 16 of the excess length holding member 12 . As a result, the annular portion 18a on the distal end side of the release linear member 18 functions as a cutting member of the retention release mechanism, and the other portion of the release linear member 18 functions as a tension member of the retention release mechanism. is formed as The surplus length portion holding member 12 that supports the other upper end portion 11b of the surplus length portion 11 also has the same configuration as the surplus length portion holding member 12 that supports the one upper end portion 11a of the surplus length portion 11 . The releasing linear member 18 normally bends and does not substantially generate tension, but when the distance between the first bridge girder 3 and the second bridge girder 4 reaches a reference value, the linear member 18 is tense and tension is generated. is set to The reference value of the distance between the first bridge girder 3 and the second bridge girder 4 is a value smaller than the maximum value of possible displacement between the first bridge girder 3 and the second bridge girder 4 .

The bridge-attached cable mounting structure 1 configured as described above operates as follows. First, when the road bridge 2 is subjected to a live load from a vehicle, a wind load, or a temperature change, the distance between the first bridge girder 3 and the second bridge girder 4 is several millimeters. to a few centimeters. Such a displacement is smaller than the reference value, and tension is not generated in the releasing linear member 18 . Therefore, the surplus length portion 11 of the cable is held in a figure 8 shape by holding the upper ends 11a and 11b by the surplus portion holding members 12 and 12. As shown in FIG. In this state, when a displacement of several millimeters to several centimeters occurs between the first bridge girder 3 and the second bridge girder 4, the cable 10 slides inside the tubular members 15 of the excess length holding members 12, 12. By doing so, the surplus length portion 11 of the cable expands and contracts while maintaining the figure-eight shape. In this way, the bridge-attached cable mounting structure 1 eliminates the influence on the cable 10 due to slight displacement between the first bridge girder 3 and the second bridge girder 4 .

On the other hand, if an earthquake or the like causes displacement between the first bridge girder 3 and the second bridge girder 4 of the road bridge 2 to exceed the reference value, the release linear member 18 is tensed to generate tension. By this tension, the connecting cords 16, 16 of the excess length holding members 12, 12 engaged with the annular portions 18a, 18a on the distal end side of the two releasing linear members 18, 18 are cut, and the excess length is cut. The connection between the upper ends 11a, 11b of and the support member 14 is released. Thus, the holding of the extra length portion 11 by the extra length portion holding members 12, 12 is released. As a result, the surplus length portion 11 of the cable can be extended, and as shown in FIG. It stretches following the displacement that occurs between them. Depending on the displacement that occurs between the first bridge girder 3 and the second bridge girder 4, the figure 8 shape of the surplus length portion 11 is eliminated. In this way, according to the bridge-attached cable mounting structure 1 of the present embodiment, even if a large displacement occurs between the bridge girders 3 and 4 due to an earthquake or the like, it is possible to effectively prevent the inconvenience of disconnection or the like in the cable 10. It can demonstrate earthquake resistance.

FIG. 4A is a cross-sectional view showing an extra length holding member and a holding release mechanism provided in the bridge attached cable mounting structure of the second embodiment of the present invention, and FIG. 4B is a plan view of the extra length holding member and the holding release mechanism. FIG. 4C is a cross-sectional view showing the extra length holding member and the holding release mechanism when an earthquake occurs. FIG. 4A is a cross-sectional view taken along line A-A' in FIG. 4B. The bridge-attached cable attachment structure of the second embodiment has the same configuration as the bridge-attached cable attachment structure 1 of the first embodiment except for the holding release mechanism. In the second embodiment, parts having the same functions as in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

The surplus length portion holding member 12 provided in the bridge attachment cable mounting structure of the second embodiment includes cylindrical members 15 provided at the upper ends 11a and 11b of the surplus length portion 11 of the cable, as in the first embodiment. , a connecting string 16 for connecting the portion of the cable 10 covered with the tubular member 15 to the support member 14 . A connecting string cutting device 23 is provided on the extra length holding member 12 . The connecting cord cutting device 23 includes a casing 24 having an arcuate recess that contacts the outer surface of the tubular member 15, a slide plate 25 that slides along the inner surface of the casing 24, and the outer surface of the slide plate 25. and a cutting blade 27 provided on the inner surface of the slide plate 25 . The casing 24 is provided with connecting string insertion holes 28 through which the connecting string 16 is inserted on the upper surface and the lower surface in FIG. 4A. Further, the casing 24 is provided with openings through which the annular portion 18a of the release linear member 18 is inserted, on the front side and the back side in FIG. 4A. This connecting cord cutting device 23 has a casing 24 attached so that the concave portion is in contact with the outer surface of a tubular member 15 , and the upper end portion of the excess length portion 11 of the cable is cut by the connecting cord 16 inserted through the connecting cord insertion hole 28 . It is connected to the support member 14 together with 11a and 11b. Also, the annular portion 18a of the releasing linear member 18 is engaged with the locking member 26 to include the outer surface of the slide plate 25, and is inserted through the opening of the casing 24 so as to include the connecting cord 16. , a releasing linear member 18 is attached. The connecting string cutting device 23 and the releasing linear member 18 constitute a holding release mechanism.

The mounting structure of the bridge attached cable of the second embodiment, in which the retention release mechanism having the above configuration is installed, is such that, due to an earthquake or the like, the load between the first bridge girder 3 and the second bridge girder 4 of the road bridge 2 exceeds the reference value. When the displacement occurs, the releasing linear member 18 is tensed to generate tension. This tension drives the slide plate 25 of the connecting cord cutting device 23, which is contained in the annular portion 18a on the distal end side of the release linear member 18, toward the back of the casing 24 as indicated by the arrow B in FIG. 4C. be done. As a result, the cutting edge 27 on the inner surface of the slide plate 25 is pressed by the connecting string 16 inserted into the casing 24 to cut the connecting string 16, thereby supporting the upper ends 11a and 11b of the extra length portion 11 of the cable. The connection between members 14 is released. As a result, the extra length portion 11 is released from being held by the extra length portion holding member 12 , and the extra length portion 11 extends following the displacement occurring between the first bridge girder 3 and the second bridge girder 4 . Thus, according to the bridge-attached cable mounting structure of the second embodiment, even if excessive displacement occurs between the first bridge girder 3 and the second bridge girder 4 due to an earthquake, disconnection or breakage of the cable 10 can be effectively prevented. can be prevented.

FIG. 5A is a plan view showing an extra length holding member and a holding release mechanism provided in the bridge attachment cable mounting structure of the third embodiment of the present invention, and FIG. 5B is a side view of the extra length holding member and the holding release mechanism. FIG. 5C is a plan view showing the extra length holding member and the holding release mechanism when an earthquake occurs. The bridge-attached cable attachment structure of the third embodiment has the same configuration as the bridge-attached cable attachment structure 1 of the first embodiment except for the holding release mechanism. In the third embodiment, parts having the same functions as in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

The surplus length portion holding member 12 provided in the bridge attachment cable mounting structure of the third embodiment includes cylindrical members 15 provided at the upper ends 11a and 11b of the surplus length portion 11 of the cable, as in the first embodiment. , a connecting string 16 for connecting the portion of the cable 10 covered with the tubular member 15 to the support member 14 . A connecting cord cutting tool 33 as shown in FIG. 5A is provided on the excess length holding member 12 . This connecting cord cutting tool 33 is formed in a generally rectangular shape in a plan view, and has a plate-like body 34 having a cutout whose depth side is enlarged, and a cutting blade 35 provided at the depth of the cutout of the plate-like body 34. . The cutouts of the plate-like body 34 are generally rectangular in plan view, and a plurality of connecting cords 16, 16, . . . , so that the connecting string cutting tool 33 is fixed in contact with the side surface of the tubular member 15 . A cutting blade 35 is fixed to the short side of the rectangular notch provided in the plate-like body 34 with the cutting edge facing the inside of the notch. The blade edge of the cutting blade 35 cuts the connecting cord 16 when the connecting cord 16 wound in contact with the long side of the notch moves relatively to the short side along with the movement of the plate-like body 34 . It is formed in a U shape so that it does. A connection hole 36 is formed on the opposite side of the plate-like member 34 of the connecting cord cutting tool 33 from the side on which the cutting blade 35 is provided, and the annular portion 18a at the tip of the release linear member 18 is inserted through the connection hole 36. and the releasing linear member 18 is connected. The connecting string cutting tool 33 and the releasing linear member 18 constitute a holding releasing mechanism.

The installation structure of the bridge attached cable of the third embodiment, in which the retention release mechanism having the above configuration is installed, is such that, due to an earthquake or the like, there is an increase in the distance between the first bridge girder 3 and the second bridge girder 4 of the road bridge 2 that exceeds the reference value. When the displacement occurs, the releasing linear member 18 is tensed to generate tension. Due to this tension, the connecting string cutting tool 33 connected to the distal end side of the releasing linear member 18 is pulled toward the connection hole 36 of the plate-like body 34 and moved. As a result, the connecting cord 16 moves relatively toward the cutting blade 35 in the notch of the plate-like body 34, and the connecting cord 16 is cut by the cutting blade 35 as shown in FIG. The connection between the upper ends 11a, 11b of the portion 11 and the support member 14 is released. As a result, the extra length portion 11 is released from being held by the extra length portion holding member 12 , and the extra length portion 11 extends following the displacement occurring between the first bridge girder 3 and the second bridge girder 4 . Thus, according to the bridge-attached cable mounting structure of the third embodiment, even if an excessive displacement occurs between the first bridge girder 3 and the second bridge girder 4 due to an earthquake, disconnection or breakage of the cable 10 can be effectively prevented. can be prevented.

FIG. 6A is a side view showing an extra length holding member and a holding release mechanism provided in the bridge attachment cable mounting structure according to the fourth embodiment of the present invention, and FIG. It is a side view which shows a release mechanism. The bridge-attached cable attachment structure of the fourth embodiment has the same configuration as the bridge-attached cable attachment structure 1 of the first embodiment except for the excess length portion holding member and the holding release mechanism. In the fourth embodiment, parts having the same functions as in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

The surplus length portion holding member 42 provided in the bridge-attached cable mounting structure of the fourth embodiment is connected to a support member 45 provided in the superstructure of the road bridge 2 . The support member 45 is fixed to the lower surface of the floor slab 44 supported by the first bridge girder 3 . The surplus length portion holding member 42 of the fourth embodiment includes an engaging metal fitting 46 detachably engaged with the support member 45 and tubular members provided at the upper ends 11a and 11b of the surplus length portion 11 of the cable. 15 and a connecting string 16 for connecting the portion of the cable 10 covered with the tubular member 15 to the engaging fitting 46 .

As shown in FIG. 6A, the engaging fitting 46 has a fitting main body 47 formed in a substantially U shape in a side view, and an engaging fitting disposed so as to face each other at the distal end portion of the U-shaped fitting main body 47 . It has a pawl 48 , an engaging screw 49 , and a connecting string attachment ring 50 connected to the metal fitting main body 47 . The support member 45 has an L-shaped cross section, the upper end of the vertical portion of the support member 45 is fixed to the floor slab 44 , and the horizontal portion of the support member 45 is engaged with an engaging fitting 46 . The engaging fitting 46 engages with the engaging screw 49 by screwing the engaging screw 49 toward the engaging claw 48 with the tip portion of the U-shaped fitting main body 47 inserted into the horizontal portion of the supporting member 45 . By sandwiching the horizontal portion of the support member 45 with the dowel 48 , it is fixed to the support member 45 . A connecting string 16 that winds the portion of the cable 10 covered with the tubular member 15 is inserted through the connecting string attachment ring 50 located below the engaging metal fitting 46 fixed to the support member 45, thereby connecting the cable. The upper ends 11a and 11b of the extra length portion 11 are held. A tip of a releasing linear member 18 as a holding release mechanism is connected to the engaging fitting 46 . Specifically, the annular portion 18 a at the tip of the releasing linear member 18 is inserted through the U-shaped metal fitting main body 47 to connect the releasing linear member 18 .

The mounting structure of the bridge attached cable of the fourth embodiment in which the excess length portion holding member 42 and the holding release mechanism of the above configuration are installed may be damaged by an earthquake or the like. If a displacement greater than a reference value occurs between , the releasing linear member 18 is tensed and tension is generated. This tension pulls the fitting body 47 of the fitting fitting 46, disengages the fitting screw 49 and the fitting claw 48 from the supporting member 45, and pulls the fitting from the supporting member 45 as shown in FIG. 6B. 46 leaves. As a result, the extra length portion 11 is released from the extra length portion holding member 42 , and the extra length portion 11 extends following the displacement occurring between the first bridge girder 3 and the second bridge girder 4 . Thus, according to the bridge-attached cable mounting structure of the fourth embodiment, even if excessive displacement occurs between the first bridge girder 3 and the second bridge girder 4 due to an earthquake, disconnection or breakage of the cable 10 can be effectively prevented. can be prevented.

FIG. 7A is a side view showing an extra length holding member and a holding release mechanism provided in the bridge attachment cable mounting structure according to the fifth embodiment of the present invention, and FIG. It is a side view which shows a release mechanism. The bridge-attached cable attachment structure of the fifth embodiment has the same configuration as the bridge-attached cable attachment structure 1 of the first embodiment except for the excess length portion holding member and the holding release mechanism. In the fifth embodiment, portions having the same functions as in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

The surplus length portion holding member 52 included in the bridge-attached cable mounting structure of the fifth embodiment is fixed to the lower surface of the floor slab 44 that constitutes the superstructure of the road bridge 2 . The floor slab 44 is supported by the first bridge girder 3 . The surplus length portion holding member 52 of the fifth embodiment includes an adsorption portion 53 that is detachably attracted to the floor slab 44 by magnetic force, and cylindrical members provided at the upper ends 11a and 11b of the surplus length portion 11 of the cable. 15 and a connecting cord 16 that connects the portion of the cable 10 covered with the tubular member 15 to the suction portion 53 .

The attraction part 53 is formed using a permanent magnet such as a neodymium magnet, and has a magnetic force capable of holding the surplus length part 11 of the cable even when an earthquake occurs. A connecting ring 54 is attached to the side opposite to the attracting surface of the attracting portion 53 , and the connecting cord 16 for winding the portion of the cable 10 covered with the tubular member 15 is inserted through and fixed to the connecting ring 54 . It is An annular portion 18a at the tip of a releasing linear member 18 as a holding releasing mechanism is inserted through the connecting ring 54, and the releasing linear member 18 is connected.

The mounting structure of the bridge attached cable of the fifth embodiment, in which the excess length portion holding member 52 and the holding release mechanism of the above configuration are installed, may be damaged by an earthquake or the like, causing the first bridge girder 3 and the second bridge girder 4 of the road bridge 2 to If a displacement greater than a reference value occurs between , the releasing linear member 18 is tensed and tension is generated. The suction portion 53 is pulled by this tension, the suction of the floor slab 44 by the suction portion 53 is released, and the suction portion 53 is separated from the floor slab 44 . As a result, the extra length portion 11 is released from being held by the extra length portion holding member 52 , and the extra length portion 11 extends following the displacement occurring between the first bridge girder 3 and the second bridge girder 4 . Thus, according to the bridge-attached cable mounting structure of the fifth embodiment, even if excessive displacement occurs between the first bridge girder 3 and the second bridge girder 4 due to an earthquake, disconnection or breakage of the cable 10 can be effectively prevented. can be prevented.

FIG. 8 is a schematic diagram showing a highway bridge 2 provided with a bridge-attached cable mounting structure 101 according to the sixth embodiment. The bridge-attached cable attachment structure 101 of the present embodiment has the same configuration as the bridge-attached cable attachment structure 1 of the first embodiment, except for the shape and arrangement position of the excess length portion 111 of the cable. In the sixth embodiment, portions having the same functions as in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

In the bridge attached cable mounting structure 101 of the sixth embodiment, the surplus length portion 111 of the cable is two windings formed at the end of the first bridge girder 3 and at the end of the second bridge girder 4 respectively. It is formed including portions 112 and 113 . These two winding portions 112 and 113 are formed by winding the cable 10 on opposite sides. Specifically, the wound portion 112 at the end of the first bridge girder 3 is wound from the front side to the back side of the paper surface from the left side to the right side in FIG. On the other hand, the winding portion 113 at the end of the second bridge girder 4 is wound from the back side to the front side of the paper as it goes from the left side to the right side in FIG. Upper ends 112a and 113a of these winding portions are supported by excess length portion holding members 12 and 12, respectively.

In the bridge-attached cable mounting structure 101 of the sixth embodiment, the proximal end portions of the two releasing linear members 18, 18 functioning as the retention release mechanism for the excess length portion holding members 12, 12 are connected to the winding portion 112, 113 are connected to bridge girders 4, 3 different from the installed bridge girders 3, 4. Specifically, the surplus length portion holding member 12 that holds the winding portion 112 arranged at the end of the first bridge girder 3 is engaged with the connecting cord 16 by the annular portion 18a on the distal end side of the release linear member 18. At the same time, the base end of this releasing linear member 18 is connected to the cross beam 20B on the side of the second bridge girder 4 . On the other hand, the excess length portion holding member 12 that holds the winding portion 113 arranged at the end of the second bridge girder 4 engages the connecting string 16 with the annular portion 18a on the tip side of the release linear member 18. At the same time, the base end of this releasing linear member 18 is connected to the horizontal beam 20A on the side of the first bridge girder 3 .

In the bridge-attached cable mounting structure 101 configured as described above, when an earthquake or the like causes a displacement greater than a reference value between the first bridge girder 3 and the second bridge girder 4 of the road bridge 2, each bridge girder 3, 4 The linear members 18, 18 for releasing connected to are tensed to generate tension. By this tension, the connecting cords 16, 16 of the excess length holding members 12, 12 engaged with the annular portions 18a, 18a on the distal end side of the two releasing linear members 18, 18 are cut, and the excess length is cut. The connection between the upper ends 112a, 113a and the support member 14 is released. In this way, the winding portions 112 and 113 of the extra length portion 111 are released from being held by the extra length portion holding members 12 and 12 . As a result, the surplus length 111 of the cable is unwound from the two windings 112 and 113 and extends following the displacement occurring between the first bridge girder 3 and the second bridge girder 4 . Here, since the two winding portions 112 and 113 are wound on the opposite sides to each other, when the winding portions 112 and 113 are untwisted, the twists of the winding portions 112 and 113 are canceled and the cable 10 is twisted. can stretch without causing In this way, according to the bridge-attached cable mounting structure 101 of the present embodiment, even if a large displacement occurs between the bridge girders 3 and 4 due to an earthquake or the like, problems such as twisting and disconnection of the cable 10 can be effectively prevented. It is possible to demonstrate high earthquake resistance.

FIG. 9 is a schematic diagram showing a road bridge 2 provided with a bridge-attached cable mounting structure 121 according to the seventh embodiment. The bridge-attached cable attachment structure 121 of the present embodiment has the same configuration as the bridge-attached cable attachment structure 1 of the first embodiment, except for the shape of the extra length portion 131 of the cable. In the seventh embodiment, portions having the same functions as in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

In the bridge-attached cable mounting structure 121 of the seventh embodiment, an extra length portion 131 formed by bending the cable 10 in a mountain shape is provided at the end portion of the first bridge 3 . An upper end portion 131 a of the mountain-shaped extra length portion 131 is supported by the support member 14 of the first bridge 3 by the extra length portion holding member 12 .

In the bridge-attached cable mounting structure 121 having the above configuration, when an earthquake or the like causes a displacement greater than a reference value between the first bridge girder 3 and the second bridge girder 4 of the road bridge 2, each bridge girder 3, 4 The release linear member 18 connected to is tensed and tension is generated. Due to this tension, the connecting cords 16, 16 of the excess length holding member 12 engaged with the annular portion 18a on the distal end side of the release linear member 18 are cut, and the upper end 131a of the excess length and the support member 14 are cut. The connection between is broken. In this way, the extra length portion 131 is released from being held by the extra length portion holding member 12 . As a result, the extra length 131 of the cable extends following the displacement occurring between the first bridge girder 3 and the second bridge girder 4 . In this way, according to the bridge-attached cable mounting structure 121 of the present embodiment, even if a large displacement occurs between the bridge girders 3 and 4 due to an earthquake or the like, problems such as twisting and disconnection of the cable 10 can be effectively prevented. It is possible to demonstrate high earthquake resistance.

In the bridge-attached cable mounting structures 1, 101, and 121 of the first, sixth, and seventh embodiments, the surplus length portions 11, 111, and 131 of the cables are held by the surplus portion holding members 12 including the connecting cords 16. In addition to supporting, the holding function of the extra length holding member 12 is released by the holding release mechanism of the release linear member 18, but other extra length holding member or holding release mechanism may be provided. For example, the bridge-attached cable mounting structures 1, 101, and 121 of the first, sixth, and seventh embodiments may be provided with a hold release mechanism using the connecting cord cutting device 23 of the second embodiment. A holding release mechanism using the connecting cord cutting tool 33 of the third embodiment may be provided, an excess length portion holding member 42 using the engaging metal fitting 46 of the fourth embodiment may be provided, or a holding member 42 of the fifth embodiment may be provided. A surplus portion holding member 52 using an adsorption portion 53 may be provided.

In addition, in the bridge-attached cable mounting structures 1, 101, and 121 of each of the above-described embodiments, the connecting cord 16 made of vinylon is used as the linear member of the excess length holding member, and the pulling member and cutting member of the holding release mechanism are used. As the linear member to be formed, the linear member 18 for releasing the wire made of stainless steel was used, but the linear member of the extra length portion holding member and the linear member of the holding release mechanism are not limited to these materials. The material is not particularly limited as long as the linear member of the holding release mechanism has a higher strength than the linear member of the extra length holding member.

Further, in each of the above-described embodiments, the reference value for the displacement between the first bridge girder 3 and the second bridge girder 4 at which the hold release mechanism operates is generated between the first bridge girder 3 and the second bridge girder 4. It can be set appropriately according to the situation. For example, the reference value can be set to the maximum possible displacement of the first bridge girder 3 and the second bridge girder 4 supported by the bridge piers 5 . In addition, an earthquake support mechanism is provided to support the first bridge girder 3 and/or the second bridge girder 4 separated from the bridge pier 5 at the time of an earthquake, and the first bridge girder 3 and the second bridge girder 4 supported by the earthquake support mechanism are provided. A displacement occurring between two bridge girders 4 may be set as a reference value.

In addition, in the first to seventh embodiments, the mounting structures 1, 101, 121 for the bridge-attached cables are arranged between the first bridge girder 3 as the first member and the second bridge girder 4 as the second member. Although installed, the first and second members are not limited to bridge girders. For example, the present invention can be widely applied between members that constitute a bridge, such as using bridge girders and abutments as the first member and the second member, where there is a possibility of displacement.

Further, each of the above-described embodiments exemplifies the case where the bridge-mounted cable mounting structure of the present invention is applied to the road bridge 2 having the bridge girders 3 and 4, but various bridge girders such as I-girders and box girders can be used. It can be applied to bridges, and the structure of bridges is not limited. Moreover, the use of bridges is not limited to roads, and the attachment structure of the bridge-attached cable of the present invention can be applied to bridges for various uses such as railways, waterworks, gas, and electric power.

The present invention is not limited to the embodiments described above, and many modifications are possible within the technical concept of the present invention by those skilled in the art.

1, 101, 121 Mounting structure of bridge attached cable 2 Road bridge 3 First bridge girder 4 Second bridge girder 6, 7 Bearing 8, 9 Cable rack 10 Cable 11, 111, 131 Extra length of cable 11a, 11b, 131a Upper ends of extra length portions 12, 42, 52 Extra length portion holding members 14, 45 Support member 15 Cylindrical member 16 Connecting cord 18 Linear member for release 18a Annular portion of linear member for release 20, 20A, 20B Cross beam 23 Connection string cutting device 27, 35 Cutting blade 33 Connection string cutting tool 44 Floor slab 46 Engagement fitting 53 Adsorption part 112, 113 Winding part 112a, 113a Upper end part of winding part

Claims (10)

A mounting structure for a communication or power cable stretched between a first member and a second member of a bridge,
an extra length portion provided near the end of the first member or the second member of the cable;
a surplus length portion holding member that holds the surplus length portion of the cable at a holding position set in the first member or the second member;
When a relative displacement exceeding a reference value occurs between the first member and the second member, the surplus length portion of the cable can be extended by releasing the holding of the surplus length portion of the cable by the surplus length portion holding member. A mounting structure for a bridge attachment cable, comprising: a holding release mechanism for In the mounting structure of the bridge attached cable according to claim 1,
wherein the excess length portion holding member includes a linear member that connects the extra length portion of the cable to the first member or the second member;
The holding release mechanism comprises a tensioning member that exerts a tensile force when a relative displacement exceeding a reference value occurs between the first member and the second member, and the excess length portion holding member due to the tensile force of the tensioning member. and a cutting member for cutting the linear member. In the mounting structure of the bridge attached cable according to claim 2,
The tension member of the holding release mechanism is formed of a linear member having a higher strength than the linear member of the excess length portion holding member,
The cutting member of the holding release mechanism is formed by bending back one end of the linear member as the tension member, and is formed of an annular portion that engages with the linear member of the excess length holding member. The installation structure of the bridge attached cable. In the mounting structure of the bridge attached cable according to claim 2,
The tension member of the retention release mechanism is formed of a linear member,
A bridge characterized in that the cutting member of the holding release mechanism is formed of a cutting blade that is driven by the tensile force of the linear member as the tensile member and cuts the linear member of the excess length holding member. Mounting structure for attached cables. In the mounting structure of the bridge attached cable according to claim 1,
The extra length holding member includes an engaging fitting that engages with the first member or the second member,
When the holding release mechanism generates a relative displacement exceeding a reference value between the first member and the second member, a tensile force is applied. An attachment structure for a bridge-attached cable, comprising a tension member for releasing engagement with the member. In the mounting structure of the bridge attached cable according to claim 1,
the excess length holding member includes a magnet that attracts the excess length of the cable to the first member or the second member;
In the holding release mechanism, when a relative displacement exceeding a reference value occurs between the first member and the second member, a tensile force acts, and the tensile force acts on the magnet to the first member or the second member. A mounting structure for a bridge-attached cable, comprising a tension member that releases the adsorption of the cable. In the mounting structure of the bridge attached cable according to claim 2, 5 or 6,
The tension member of the holding release mechanism is connected to a member different from the member in which the extra length portion released by the holding release mechanism is arranged, out of the first member and the second member. The installation structure of the bridge attached cable. In the mounting structure of the bridge attached cable according to claim 1,
A mounting structure for a bridge-attached cable, wherein a surplus length portion of the cable at the holding position is bent in a mountain shape. In the mounting structure of the bridge attached cable according to claim 1,
An attachment structure for a bridge-attached cable, wherein a surplus length portion of the cable at the holding position is bent in a figure-of-eight shape. In the mounting structure of the bridge attached cable according to claim 1,
An attachment structure for a bridge-attached cable, wherein the surplus length portion of the cable at the holding position is formed of two wound portions wound on opposite sides.

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