JP5953332B2 - Cable lead-in structure - Google Patents

Description

  The present invention relates to a cable lead-in structure.

  Some seismic isolation structures support the upper structure via the seismic isolation device. In this type of seismic isolation structure, the seismic isolation device is greatly and slowly deformed in the event of an earthquake to reduce the seismic motion input to the structure. For this reason, when an earthquake occurs, a large relative displacement occurs between the lower structure and the upper structure. Therefore, when various cables are pulled into the seismic isolation structure, in addition to not damaging the function as a cable due to the influence of the earthquake, it is also necessary to follow a large relative displacement. In such a base-isolated structure, when pulling the cable from the lower structure to the upper structure, the cable should not be stretched even if the relative displacement between the lower structure and the upper structure is maximum. A sufficient surplus part is provided in the cable, and this surplus part is arranged between the lower structure and the upper structure in a seismic isolation pit provided with a seismic isolation device (for example, (See Patent Documents 1 and 2).

JP 2001-292524 A JP-A-11-346430

  In the technique disclosed in Patent Literature 1, the extra length portions are gathered together in a spiral shape, and in the technique disclosed in Patent Literature 2, the extra length portions are gathered using a special jig. However, a cable with a large diameter and high rigidity requires a very large space in the seismic isolation pit in order to gather the extra length in a spiral or to gather the extra length using a jig. It is actually difficult. Also, with these methods, in the case of a cable with a large diameter and high rigidity, the cable may not behave stably due to the interference of the cable itself or the reaction force from a special jig, etc. There is a possibility that a part where deformation is concentrated locally occurs, resulting in functional failure.

  The present invention is capable of compactly gathering extra length parts even with a cable having a large diameter and high rigidity, behaves stably in the event of an earthquake, disperses the bending deformation that occurs in the cable, and deforms to a specific location. The purpose of the present invention is to provide a cable lead-in structure that can prevent the concentration of the cable.

In order to achieve the above object, the present invention provides a cable pulling structure from the lower structure to the upper structure of a base isolation structure in which the upper structure is supported on the lower structure via a base isolation device. The horizontal direction which is a substantially horizontal direction is the first extending direction of the cable, the cable is fixed to the lower structure at a fixed portion at the bottom of the cable, and the vertical direction which is a substantially vertical direction is the cable. In the second extending direction, the cable is fixed to the upper structure at the upper fixed portion of the cable, and an extra length portion is provided between the lower fixed portion and the upper fixed portion, The surplus part is a base end that curves and extends so as to have a center on one side divided in the horizontal direction by an extension line along the first extending direction of the cable in the lower fixed part . And the lower part of the upper fixed part A raised portion extending curved so as to have a center fixed portion side of the lower, a curved portion provided between the raised portion and the curved portion of the proximal end of the curved portion The center of the curved portion of the base end and the curved portion of the upright portion is centered on the opposite side of the curved portion with respect to the cable, and friction between the cable and the lower structure is reduced. a friction-reducing part provided so as to, have a, the rising portion as launch toward the upper structure from the friction reducing unit, securing the cable, characterized in that.

  In this way, the base end curve in which the extra length portion is curved and extended so as to have a center on one side with respect to the extension line from the lower fixed portion fixed laterally to the lower structure. And at least one intermediate curved portion that is curved to have a center on the opposite side with respect to the adjacent curved portion including the curved portion at the base end, and the center from the middle curved portion to the lower fixed portion side Therefore, even if the cable has a large diameter and high rigidity, the extra length can be compactly gathered. Therefore, the laying space for the extra length can be reduced. Moreover, since the height of most of the extra length portion can be suppressed, the extra length portion can be laid even if the seismic isolation pit is narrow in the height direction. In addition, the extra length can be held in a state that can be satisfactorily deformed without using a special jig.

  In addition, the inflection point between the adjacent curved portions and the curved portion and the inflection point between the curved portion and the upright portion have a small curvature and can be deformed greatly without stress. The deformation of the extra length portion caused by the relative displacement of the lower fixed portion and the upper fixed portion can be absorbed by the portions having a small curvature. Therefore, it can suppress that a deformation | transformation concentrates locally within an extra length part, and can make it hard to produce damage. In addition, in order to provide an inflection point that is easy to deform between the bending portion and the bending portion, both of which are difficult to deform, and to provide an inflection point that is easy to deform between the bending portion that is difficult to deform and the upright part, When the earthquake occurs, the entire surplus part will behave in a stable manner with a good balance. Also from this point, it is possible to prevent local deformation from concentrating in the surplus length portion, and it is difficult to cause damage.

It said friction reducing unit may be kicked set between said lower structure and the extra length portion. If comprised in this way, the damage by the friction between the lower structure of a surplus length part can be suppressed.

  A plurality of the cables may be juxtaposed in the horizontal direction. If comprised in this way, even when laying a plurality of cables, the extra length portions of the plurality of cables can be gathered in a compact manner, and as a result, the laying space can be reduced.

  According to the present invention, even with a cable having a large diameter and high rigidity, the extra length portion can be gathered in a compact manner, behaves stably when an earthquake occurs, and distributes bending deformation generated in the cable to a specific place. It is possible to prevent the deformation from concentrating on.

BRIEF DESCRIPTION OF THE DRAWINGS The drawing-in structure of the cable which concerns on one Embodiment of this invention is shown, (a) is a top view, (b) is a side view. It is a perspective view which shows the drawing-in structure of the cable which concerns on one Embodiment of this invention. It is a top view which shows the modification of the drawing-in structure of the cable which concerns on one Embodiment of this invention.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, the seismic isolation structure 1 is configured such that an upper structure 4 is supported on a lower structure 2 via a seismic isolation device 3. A plurality of base isolation devices 3 (only one unit is shown in FIG. 1B because FIG. 1 is a partial view) are mounted on the lower structure 2, and the upper structure is mounted on these base isolation devices 3. 4 is installed. The seismic isolation device 3 is, for example, a laminated rubber isolator or the like in which rubber plates and metal plates are alternately laminated in the vertical direction, and is deformed and absorbs energy when an earthquake occurs. A space between the lower structure 2 and the upper structure 4 in which the seismic isolation device 3 is arranged is a seismic isolation pit 5.

  The cable lead-in structure of the present embodiment is a cable pull-in structure of the cable 10 from the lower structure 2 to the upper structure 4 of the seismic isolation structure 1 as described above. The cable 10 is a communication cable or a power cable, and has a diameter as large as, for example, 70 mm and high rigidity. The cable 10 is fixed to the upper surface 2 a of the lower structure 2 by a lower fixing bracket 11 and is fixed to the side surface 4 a of the upper structure 4 by an upper fixing bracket 12. In the cable 10, an inner portion of the lower fixing bracket 11 is a lower fixed portion 15 that is fixed to the lower structure 2 by the fixing bracket 11, and an inner portion of the upper fixing bracket 12 is the fixing bracket 12. Thus, an upper fixed portion 17 fixed to the upper structure 4 is formed.

  In the cable 10, a lower extending portion 16, which is opposite to the upper fixed portion 17 with respect to the lower fixed portion 15, is laid horizontally on the upper surface 2 a of the lower structure 2. The fixed portion 15 is also laid horizontally on the upper surface 2 a of the lower structure 2. The lower fixed portion 15 has a linear shape and is arranged in the horizontal direction.

  Further, the cable 10 has an upper extending portion 18 on the side opposite to the lower fixed portion 15 with respect to the upper fixed portion 17 laid vertically on the side surface 4 a of the upper structure 4. The upper fixed portion 17 is also laid vertically on the side surface 4 a of the upper structure 4. The upper fixed portion 17 has a linear shape and is arranged in the vertical direction.

  Here, as shown in FIG. 1A, the fixing member 12 is fixed to the upper structure 4 by the fixing metal 12 on the extension line in the plan view of the lower fixed part 15 fixed to the lower structure 2 by the fixing metal 11. An upper fixed portion 17 is disposed.

  As shown in FIG. 1 and FIG. 2, the cable 10 has an extra length portion between the lower fixed portion 15 and the upper fixed portion 17 that is longer than a length connecting them with a straight line. 21 is provided. The extra length portion 21 is centered on one horizontal side with respect to the extension line of the lower fixed portion 15 from the end opposite to the lower extending portion 16 of the lower fixed portion 15. It has a curved portion 22 at the base end that is curved and extends horizontally. Further, the extra length portion 21 extends vertically downward from the end portion on the opposite side of the upper extension portion 18 of the upper fixed portion 17 in a straight line on the extension line of the upper fixed portion 17. And a raised portion 24 that curves and extends from the end opposite to the fixed portion 17 on the upper side of the linear portion 23 to the lower fixed portion 15 side. Have. Further, the extra length portion 21 is an intermediate portion that is curved so as to have a center on the horizontal opposite side of the cable 10 with respect to the adjacent proximal end curved portion 22 between the proximal curved portion 22 and the upright portion 24. A curved portion 25 is provided. Here, only one intermediate curved portion 25 is formed. The intermediate curved portion 25 has one end extending from the end opposite to the fixed portion 15 below the proximal curved portion 22 and the other end opposite to the fixed portion 17 above the raised portion 24. It extends from the end of the side.

  Thus, the lower fixing bracket 11 and the lower fixed portion 15 serve as the first fixing point 31 of the cable 10 to the lower structure 2, and the upper fixing bracket 12 and the upper fixed portion 17 are the upper structure. It becomes the second fixing point 32 of the cable 10 to the body 4. The surplus length portion 21 is formed between the first fixed point 31 and the second fixed point 32 of the cable 10, and the surplus length portion 21 includes a proximal end curved portion 22 and an intermediate curved portion 25. A first inflection point 33 is formed between the second bending point 34 and the middle bending portion 25 and the upright portion 24.

  In other words, the cable 10 has two inflection points of the first inflection point 33 and the second inflection point 34 between the two fixing points of the first fixing point 31 and the second fixing point 32. Inflection points are formed. Of the two inflection points, the first inflection point 33 closer to the first fixed point 31 is a curved portion 22 at the base end that is disposed horizontally and the opposite side of the curved portion 22. The inflection point with the intermediate bending portion 25 arranged horizontally except for. Of the two inflection points, the second inflection point 34 that is closer to the second fixed point 32 has a portion that rises slightly from the portion of the intermediate curved portion 25 that is disposed horizontally, and a stand that rises further. It is an inflection point between the upper part 24. Between the second fixed point 32 and the second inflection point 34 which is closer to the second fixed point 32, the arcuate upright portion 24 and the linear portion 23 are combined.

  The bending portion 22 at the proximal end, the middle bending portion 25, and the upright portion 24 are all bent so that the curvature is equal. Further, the curved portion 22 at the proximal end has an arc shape with a central angle of about 90 °, the intermediate curved portion 25 has an arc shape with a central angle of about 180 °, and the upright portion 24 has a central angle. It has an arc shape of about 90 °. As a result, the intermediate curved portion 25 is longer than the proximal curved portion 22 and the upright portion 24. The entire surplus length portion 21 is provided in one of the two regions partitioned by a line connecting the lower fixed portion 15 and the upper fixed portion 17 in plan view. .

  Between the lower structure 2 and the surplus length part 21, a friction coefficient 41 having a smaller friction coefficient than these and reducing the friction between them is provided. The friction reducing portion 41 is provided on the upper surface 2a of the lower structure 2, and includes, for example, a fluorine resin coating layer such as polytetrafluoroethylene, a sheet material of the same resin, a stainless steel plate, a frame with casters, or the like. Yes. The area and position of the friction reduction part 41 are set so that the extra length part 21 does not directly contact the lower structure 2 even when an earthquake occurs.

  According to the embodiment described above, the surplus length portion 21 has a center on one horizontal side with respect to the extension line from the lower fixed portion 15 fixed laterally to the lower structure 2. A curved portion 22 of the proximal end that extends in a curved manner, an intermediate curved portion 25 that curves to have a center on the horizontal opposite side of the cable 10 with respect to the curved portion 22 of the proximal end, and this intermediate curved portion A rising portion 24 that curves and rises from the portion 25 toward the lower fixed portion 15 side, and a linear shape that extends from the rising portion 24 in a straight line and connects to the upper fixed portion 17 in the vertical direction. Because of the shape having the portion 23, the extra length portion 21 can be gathered in a compact manner even with the cable 10 having a large diameter and high rigidity. Therefore, the laying space for the extra length portion 21 can be reduced. Moreover, since most heights of the surplus length part 21 can be suppressed, even if the seismic isolation pit 5 is narrow in the height direction, the surplus length part 21 can be laid. Moreover, by setting it as the said structure, the surplus length part 21 can be hold | maintained in the state which can deform | transform favorably, without using a special jig | tool.

  Further, a first inflection point 33 between the adjacent bent portion 22 and the intermediate bent portion 25, and a second inflection point 34 between the intermediate bent portion 25 and the upright portion 24, Since the linear portion 23 is a portion having a small curvature and capable of being deformed greatly without stress, deformation of the extra length portion 21 caused by relative displacement of the lower fixed portion 15 and the upper fixed portion 17 when an earthquake occurs. Can be absorbed by these small curvature portions. Therefore, it can suppress that a deformation | transformation concentrates locally in the surplus length part 21, and can make it hard to produce damage.

  In addition, a first inflection point 33 that is easy to deform is provided between the base bending portion 22 and the intermediate bending portion 25 that are difficult to deform, and the intermediate bending portion 25 and the upright portion that are both difficult to deform. Since the second inflection point 34 that is easily deformed is provided between the first and second members 24, the surplus length portion 21 as a whole behaves in a well-balanced and stable manner when an earthquake occurs. Also from this point, it is possible to suppress the local concentration of deformation in the surplus length portion 21 and to prevent damage.

  Moreover, since the friction reduction part 41 which reduces friction is provided between the lower structure 2 and the surplus length part 21, the damage by the friction between the surplus structure 21 and the lower structure 2 is suppressed. be able to.

  In the above embodiment, the case where only one intermediate bending portion 25 is provided between the proximal bending portion 22 and the upright portion 24 has been described as an example. However, a plurality of intermediate bending portions 25 are provided. May be. In that case, all the middle curved portions 25 are curved with respect to adjacent ones of the proximal curved portion 22 and the middle curved portion 25 so as to be centered on the horizontal opposite sides of the cable 10. become. That is, the adjacent curved portions are bent in opposite directions in the horizontal plane.

  Moreover, in the above embodiment, the linear part 23 which forms a straight line from the upper fixed part 17 and extends downward is provided, and the upper fixed part 17, the upright part 24, However, the linear portion 23 may not be provided. That is, the upright portion 24 only needs to be curved and extend below the upper fixed portion 17 so as to have a center on the lower fixed portion 15 side. When the linear portion 23 is not provided, the upright portion 24 extends from the lower end portion of the upper fixed portion 17 so as to have a center on the lower fixed portion 15 side.

  In the above embodiment, the drawing structure of one cable 10 has been described as an example, but the present invention can be applied to a plurality of cables 10. In that case, as shown in FIG. 3, one cable 10 is wired in the above shape, and the other cables 10 are wired in the same shape as the above, and a plurality of cables 10 are arranged in parallel in the horizontal direction. I will let you. Thereby, even when a plurality of cables 10 are laid, the extra length portions 21 of the plurality of cables 10 can be gathered in a compact manner, and as a result, the laying space can be reduced.

  Moreover, in the above embodiment, the case where the base end curved portion 22, the intermediate curved portion 25, and the upright portion 24 are all curved in an arc shape has been described as an example, but other curved shapes such as a suspended curve shape are described. It is also good.

DESCRIPTION OF SYMBOLS 1 Seismic isolation structure 2 Lower structure 3 Seismic isolation apparatus 4 Upper structure 10 Cable 15 Lower fixed part 17 Upper fixed part 21 Extra length part 22 Base part curved part 24 Standing upper part 25 Middle curved part 41 Friction reduction part

Claims (3)

A cable pull-in structure from the lower structure to the upper structure of the base isolation structure that supports the upper structure via the base isolation device to the lower structure,
The horizontal direction that is the substantially horizontal direction is the first extending direction of the cable, and is fixed to the lower structure at the fixed portion at the lower part of the cable, and the vertical direction that is the substantially vertical direction is the second extending direction of the cable. In the direction, the cable is fixed to the upper structure at the upper fixed portion of the cable, and an extra length portion is provided between the lower fixed portion and the upper fixed portion,
The extra length portion is
A proximal curved portion extending in a curved manner so as to have a center on one side divided in two horizontally by an extension line along a first extending direction of the cable in the lower fixed portion;
An upright portion extending in a curved manner so as to have a center on the lower fixed portion side below the upper fixed portion;
A bending portion provided between the bending portion of the proximal end and the upright portion , wherein the center of the bending portion is located between the bending portion of the proximal end and the bending portion of the rising portion with respect to the cable. a curved portion on the side opposite the side with the center of both,
A friction reducer provided to reduce friction between the cable and the lower structure;
I have a,
Said rising portion so as to raise up toward the upper structure from the friction reducing unit, securing the cable,
A cable lead-in structure characterized by that. The friction reducing part is
Pull the cable construction according to claim 1, characterized in that it kicked set between the extra length portion and the lower structure. The cable lead-in structure according to claim 1 or 2, wherein a plurality of the cables are arranged in parallel in the horizontal direction.

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