JP2001292524A - Structure for drop cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive a drop cable, capable of absorbing the load applied to a cable in case of earthquake, without having to use additional parts. SOLUTION: A base-isolation support apparatus 5 is placed on a foundation 6, and a building (upper structure) 8 is supported for base isolation via a frame 7 by the base-isolation support apparatus 5. An oil-immersed cable 4 which is led in a space 9 from the outside and another cable 4 disposed in a space 9 under a floor from a distribution board in the building 8 are connected via an under-floor cable 1A having a margin of a length approx. 1 m.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cable lead-in structure for a seismic isolation building from outdoors to indoors.

[0002]

2. Description of the Related Art Conventionally, as a similar technique, for example, Japanese Unexamined Patent Publication No. Hei. 5-184039 discloses a method in which a panel or the like installed on a seismically isolated floor and a device installed on a non-seismic part are used. A supporting structure (retraction structure) of a cable to be tied is described.

In this cable lead-in structure, the cable is supported by a cable support device made of an elastic material having a sliding surface, and a load generated on the cable during vibration is absorbed by friction of the sliding surface and deformation of the elastic material. It is formed so that.

[0004]

SUMMARY OF THE INVENTION The above-mentioned Japanese Patent Application Laid-Open No. 5-184.
More specifically, the cable support device disclosed in Japanese Patent No. 039 is a structure in which a cable is wired around a loop-shaped elastic body whose diameter can be reduced, or a structure in which two points of a cable having slack are connected by an elastic material. Alternatively, there is a structure in which a cable is wired so as to sew between a plurality of elastic rods. In each case, the elastic material absorbs a bending load or a tensile load applied to the cable. However, each of the above cable support devices requires special parts. In addition, all of the cable support devices have directionality in absorbing the load applied to the cable due to the relative movement in the horizontal direction between the seismically isolated floor and the non-seismic portion.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and provides a low-cost cable lead-in structure capable of absorbing a load applied to a cable during an earthquake without using special parts. It is an object. It is another object of the present invention to provide a cable lead-in structure having no directivity in absorbing performance of a load applied to a cable.

[0006]

According to the first aspect of the present invention, there is provided a seismic isolation building in which an upper structure is seismically isolated from a foundation by a seismic isolation bearing device installed in an underfloor space. An underfloor cable having a length that is larger than a relative moving distance between the upper structure and a foundation during an earthquake, wherein the cable is led from an outdoor to an underfloor space. A cable lead-in structure characterized by being connected to a cable in a room via a cable.

The term "cable" in the present invention means a power cable, a ground cable, a signal cable such as a twisted pair cable or a multi-core cable, a coaxial cable, an optical communication cable, or the like. Also, the extra cable length depends on the magnitude of the anticipated earthquake,
Usually, it is sufficient to set it to 40 cm or more and 100 cm or less.
The underfloor space may be embankment or a solid solid foundation, but it is preferable to cover the surface with a smooth sheet such as a waterproof sheet to protect the cable.

According to a second aspect of the present invention, in the first aspect of the present invention, there is provided a cable lead-in structure, wherein the underfloor cable is formed by bending up and down. As a method of bending the underfloor cable up and down, a bar-shaped hanger is fixed to the upper structure, and a cable is hooked around the hanger, or a plurality of hangers is fixed to the upper structure, and the slack is loosened. A method such as hooking a cable that has been used can be adopted. It is also effective to fix a rod-shaped hanger to the upper structure, attach a movable hanger to the rod-shaped hanger, and slack and hook the cable to the hanger.

According to a third aspect of the present invention, there is provided the cable lead-in structure according to the first aspect, wherein the underfloor cable is formed to be bent substantially horizontally. As the shape of the underfloor cable bent almost horizontally,
A zigzag shape or a loop shape is preferable. As a method of bending the underfloor cable horizontally, it is economical and effective to form the above shape manually at a construction site. In addition, when the underfloor cable is arranged on a flat plate having a small slip resistance on the surface, it is possible to prevent the underfloor cable from vibrating during an earthquake and being damaged by friction with a surface such as a foundation.

[0010] The invention according to claim 4 is based on claim 1,
In the invention according to the second or third aspect, the underfloor cable is disposed in a flexible protective tube.

According to a fifth aspect of the present invention, there is provided a seismic isolation building in which an upper structure is seismically isolated from a foundation by a seismic isolation bearing device installed in a space under the floor, and a cable lead-in structure from the outdoors to the room. In addition, the cable is guided from the outdoors to the underfloor space, and is connected to the indoor cable through a vibration absorbing device having no directionality in the horizontal direction with respect to the relative movement between the upper structure and the foundation. A cable pull-in structure characterized by the following.

According to a sixth aspect of the present invention, there is provided a cable lead-in structure according to the fifth aspect, wherein the vibration absorbing device is a spirally formed underfloor cable. As a method of forming the cable in a spiral shape, the cable may be formed in a spiral shape at the time of manufacturing the cable. Alternatively, the cable may be formed at a construction site by winding a linear cable around a cylindrical jig. Further, it is preferable that a spirally formed cable be vertically hung from an indoor cable and connected to a cable from the outdoors, since the directionality in the horizontal direction can be particularly eliminated.

According to a seventh aspect of the present invention, in the fifth aspect of the present invention, the vibration absorbing device is an underfloor cable disposed in a spirally formed flexible protective tube. The feature is a cable pull-in structure. The flexible protective tube may be formed spirally at the time of manufacturing the protective tube, or may be formed by spirally assembling the protective tube at a construction site.

According to an eighth aspect of the present invention, in the invention of the sixth or seventh aspect, the helically formed underfloor cable or flexible protective tube is erected in an underfloor space in contact with them. A retraction structure characterized by being held in an underfloor space by an elastic shape holding material.
Although the shape protection material of the present invention is not particularly limited, it can be easily formed by erecting a plurality of rods made of metal, synthetic resin, or the like in the underfloor space. The method of holding the underfloor cable or the flexible protective tube on the shape maintaining material is not particularly limited, but it is simple and effective to tie the underfloor cable or the like with a string or a metal wire.

The seismic isolation bearing device in the present invention is not particularly limited, but a device utilizing a laminated rubber bearing, a double dish type bearing, a sliding bearing or the like is effective.

[0016]

In the cable lead-in structure according to the first aspect of the present invention, the cable is connected to the indoor cable via an underfloor cable having a length larger than the relative movement distance between the upper structure and the foundation during an earthquake. Have been. Therefore, even if the upper structure and the foundation relatively vibrate during the earthquake, no load is applied to the underfloor cable.

In the cable lead-in structure according to the second aspect of the present invention, the underfloor cable is formed to be bent up and down. Therefore, the load applied to the cable during an earthquake can be absorbed without using any special parts.

In the cable lead-in structure according to the third aspect of the present invention, the underfloor cable is bent substantially horizontally. Therefore, the load applied to the cable during an earthquake can be absorbed without using any special parts.

In the cable lead-in structure according to the fourth aspect of the present invention, the underfloor cable is disposed in a flexible protective tube. Therefore, there is no possibility that the underfloor cable directly contacts the ground surface of the underfloor space or the upper structure during an earthquake and is damaged.

In the cable lead-in structure according to the fifth aspect of the present invention, the cable from the outside can be connected indoors through a vibration absorbing device having no directivity in the horizontal direction with respect to the relative movement between the upper structure and the foundation. Connected to cable. Therefore, the load applied to the cable can be absorbed uniformly regardless of the direction in which the earthquake shakes.

In the cable lead-in structure according to the sixth aspect of the present invention, the vibration absorbing device is a helically formed underfloor cable. In other words, just connect the outdoor cable and the indoor cable with the spirally formed cable,
It can absorb the load applied to the cable regardless of the direction of the earthquake.

In the cable pull-in structure according to the seventh aspect of the present invention, the underfloor cable, which is a vibration absorbing device, is disposed in a spirally formed flexible protective tube. Therefore, there is no possibility that the underfloor cable directly contacts the ground surface of the underfloor space or the upper structure during an earthquake and is damaged. Further, it is not necessary to form the underfloor cable in a spiral shape, and the underfloor cable can be formed in a spiral shape simply by being drawn into the protective tube, and the load applied to the cable can be absorbed regardless of the direction in which the earthquake shakes.

In the cable pull-in structure according to the present invention, the helically formed underfloor cable or the flexible protective tube has an elastic shape which is erected in the underfloor space in contact with them. It is held in the underfloor space by holding material. Therefore, the underfloor cable can be effectively held spirally. In addition, even after an earthquake, the underfloor cable can be kept spiral.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on embodiments with reference to the drawings. FIG. 1 shows a first embodiment of the cable lead-in structure of the present invention. In FIG. 1, a seismic isolation bearing device 5 is placed on a foundation 6 which is a solid foundation. The seismic isolation bearing device 5 supports the building (upper structure) 8 via the gantry 7. In this building 8, a lead-in cable 3 for power supply is guided from outside to a space 9 under the floor through a conduit 31 buried underground. Further, from inside the building 8, the cable 4 is guided from the distribution board inside the building 8 to the underfloor space 9 through a conduit 41 arranged in the underfloor space 9. These cables 3 and 4 are connected via an underfloor cable 1A having a margin of about 1 m. In addition, the incoming cable 3, the underfloor cable 1A, and the indoor cable 4 are drawn into the room from outside as one cable. The extra length of the underfloor cable 1A is placed on a polyethylene plate 3A having a smooth surface provided on the foundation 6 and wound flatly.

As described above, since the underfloor cable 1A is provided, even if the building 8 and the foundation 6 vibrate relatively during an earthquake, no load is applied to the underfloor cable 1A, and the underfloor cable 1A is not applied. No rubbing. That is, even if an earthquake occurs, the cable 4 in the building 8, the cable 1A under the floor, and the incoming cable 3 from the outside are not damaged.

Hereinafter, another embodiment will be described with a focus on portions different from FIG. FIG. 2 shows a second embodiment of the cable lead-in structure of the present invention. In the underfloor space 9 of the building 8,
A bar-shaped hanger 3B is provided, and an underfloor cable 1 is provided.
B is bent up and down so as to surround the hanger and is hooked. As described above, since the underfloor cable 1B is hooked on the hanger 3B with a sufficient length, the load applied to the cable during an earthquake can be absorbed without using any special parts. Further, it is possible to prevent the underfloor cable 3B from being rubbed against the foundation 6 and damaged.

FIG. 3 shows a third embodiment of the cable lead-in structure of the present invention.
It shows an embodiment. The underfloor cable 1C is disposed in a bent flexible protective tube 11C. Therefore, the underfloor cable 1C does not come into direct contact with the foundation 6 or the building 8 during an earthquake and is not damaged. In addition, even under normal conditions, the underfloor cable 1C can be protected from damage such as rat damage.

FIG. 4 shows a fourth embodiment of the cable lead-in structure of the present invention.
It shows an embodiment. The underfloor cable 1D is formed in a spiral shape. The underfloor cable 1D is vertically hung from the building 8, and serves as a vibration absorber having no direction in the horizontal direction with respect to the relative movement between the building 8 and the foundation 6. The underfloor cable 1D is formed by winding a straight cable around a cylindrical jig at a construction site.

FIG. 5 shows a fifth embodiment of the cable lead-in structure of the present invention.
It shows an embodiment. The underfloor cable 1E is disposed in a spirally formed flexible protective tube 11E. This flexible protective tube 11E is
The underfloor cable 1E is formed into a spiral shape by being drawn into the protective tube 11E when the protective tube is manufactured, and has a directivity in the horizontal direction with respect to the relative movement between the building 8 and the foundation 6. There is no vibration absorber.

FIG. 6 shows a sixth embodiment of the cable lead-in structure of the present invention.
It shows an embodiment. The spirally formed underfloor cable 1F is connected to a stainless steel resilient shape holding member 3F provided upright in the underfloor space 9 in contact with the spirally underfloor cable 1F with a stainless steel wire (not shown). Thus, it is held in the underfloor space. Therefore, the underfloor cable 1F can be effectively held spirally. Further, even after the occurrence of an earthquake, the underfloor cable 1F can be kept spiral.

Although the embodiment of the present invention has been described with reference to the drawings, the specific configuration of the present invention is not limited to this embodiment, and there are design changes and the like that do not depart from the gist of the present invention. Are also included in the present invention.

For example, an incoming cable from outside may not be buried underground. Further, the drop-in cable, the underfloor cable, and the indoor cable may be connected to each other using a connector or the like.

[0033]

In the cable lead-in structure according to the first aspect of the present invention, indoor cables are provided via underfloor cables having a length larger than the relative movement distance between the upper structure and the foundation during an earthquake. Is connected to Therefore,
Even if the superstructure and the foundation vibrate relatively during an earthquake,
Since no load is applied to the underfloor cable, it is possible to prevent the cable from being disconnected or damaged.

In the cable lead-in structure according to the second aspect of the present invention, since the underfloor cable is formed by bending up and down, the load applied to the cable during an earthquake can be absorbed without using any special parts. it can. That is, it is possible to configure a cable lead-in structure in which the cost of parts is low and the workability is excellent.

In the cable lead-in structure according to the third aspect of the present invention, the underfloor cable is formed by bending up and down. Therefore, the load applied to the cable during an earthquake can be absorbed without using any special parts.

In the cable lead-in structure according to the fourth aspect of the present invention, the underfloor cable is disposed in a flexible protective tube. Accordingly, since the underfloor cable does not directly contact the ground surface of the underfloor space or the upper structure during an earthquake and is not damaged, the reliability of the wiring can be further improved.

In the cable lead-in structure according to the fifth aspect of the present invention, the load applied to the cable can be absorbed irrespective of the direction in which the earthquake shakes, so that the reliability of the cable lead-in structure during an earthquake can be reduced. Can be more enhanced.

In the cable lead-in structure according to the sixth aspect of the present invention, the vibration absorbing device is a helically formed underfloor cable. That is, by simply connecting the outdoor cable and the indoor cable with the spirally formed cable, the load applied to the cable can be absorbed regardless of the direction in which the earthquake shakes. Therefore, the load applied to the cable during an earthquake can be absorbed without using any special parts.

In the cable lead-in structure according to the present invention, the underfloor cable is disposed in a spirally formed flexible protective tube. Therefore, there is no possibility that the underfloor cable directly contacts the ground surface of the underfloor space or the upper structure during an earthquake and is damaged. Further, the underfloor cable does not need to be formed in a spiral shape, but can be formed into a spiral shape simply by being drawn into the protective tube, and can absorb the load applied to the cable regardless of the direction of the earthquake. That is, the load applied to the cable during an earthquake can be absorbed without using any special parts.

In the cable pull-in structure according to the present invention, the helically formed underfloor cable or the flexible protective tube is provided with an elastic underfloor space standing in contact with them. It is held in the underfloor space by a certain shape holding material. Therefore, the underfloor cable can be effectively held spirally. In addition, even after an earthquake, the underfloor cable can be kept spiral.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment of a cable lead-in structure of the present invention.

FIG. 2 is a sectional view showing a second embodiment of the cable lead-in structure of the present invention.

FIG. 3 is a sectional view showing a third embodiment of the cable lead-in structure of the present invention.

FIG. 4 is a sectional view showing a fourth embodiment of the cable lead-in structure of the present invention.

FIG. 5 is a sectional view showing a fifth embodiment of the cable lead-in structure of the present invention.

FIG. 6 is a sectional view showing a sixth embodiment of the cable lead-in structure of the present invention.

[Explanation of symbols]

 1A, 1B, 1C Underfloor cable 1D, 1E, 1F Underfloor cable (vibration absorber) 11C, 11E Protective tube 3 Drop-in cable (outdoor cable) 4 Cable from distribution board (indoor cable) 5 Seismic isolation support device 6 Foundation 8 Building (superstructure) 9 Underfloor space

Claims (8)

[Claims] 1. A base-isolated building whose upper structure is seismically isolated from a foundation by a seismic isolation bearing device installed in the underfloor space.
An underfloor cable having a length that is larger than a relative moving distance between the upper structure and a foundation during an earthquake, wherein the cable is led from an outdoor to an underfloor space. A cable lead-in structure which is connected to a cable in a room through a cable. 2. The cable pull-in structure according to claim 1, wherein the underfloor cable is formed by being bent up and down. 3. The cable pull-in structure according to claim 1, wherein the underfloor cable is formed by being bent substantially horizontally. 4. The underfloor cable is disposed within a flexible protective tube.
The cable pull-in structure according to 2 or 3. 5. A base-isolated building whose upper structure is seismically isolated from a foundation by a seismic isolation bearing device installed in the underfloor space,
A cable lead-in structure from the outdoors to the room, wherein the cables are guided from the outdoors to the underfloor space, and are passed through a vibration absorbing device having no direction in the horizontal direction with respect to the relative movement between the upper structure and the foundation. A cable lead-in structure characterized by being connected to an indoor cable. 6. The cable pull-in structure according to claim 5, wherein said vibration absorbing device is a spirally formed underfloor cable. 7. The cable lead-in structure according to claim 5, wherein said vibration absorbing device is a cable under the floor disposed in a flexible protective tube formed in a spiral shape. 8. The underfloor cable or the flexible protective tube formed in a spiral shape is held in the underfloor space by a resilient shape holding material erected in the underfloor space in contact with them. The cable pull-in structure according to claim 6 or 7, wherein: