JP2006003350A - Inter-two-point displacement gage by optical fiber, and remote monitoring method for displacement between two points - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique capable of detecting quickly and properly a displacement amount of a structure all the time or in a disaster such as earthquake, in particular, a displacement amount between two points, even in a prescribed remote site. <P>SOLUTION: An abutment or a pier 37 is arranged in a lower position between one girder 35 and the other girder 36, in the one girder 35 as the structure and the other girder 36 as the structure. The pier 37 may be constituted of a skeleton. An inter-two-point displacement gage 38 is arranged on an upper face of the pier 37, the inter-two-point displacement gage 38 is mounted with an optical fiber fixing jig, a rotatable optical fiber winding member comprising a plurality or a large number of pulleys constituted of a plurality of lines, and a displacement/load conversion member comprising a coil spring or the like, one side and the other side optical fibers 39, 40 having a strain sensor function are extracted from the inter-two-point displacement gage 38, and the one side optical fiber 39 is connected to a BOTDR (Brilloin Optical Time Domain Reflectometer) instrument 46. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to an optical fiber two-point displacement meter and a two-point displacement remote monitoring method using an optical fiber for detecting displacement between two points at the time of a disaster such as an earthquake or an earthquake.

Conventionally, a first example of this type is disclosed in Japanese Patent Laid-Open No. 2002-90233 shown in FIG. To explain this, a bridge 2 is erected on the river 1. And the support | pillars 3 and 4 are standingly arranged by the appropriate space | interval on the river 1, The girder 5a, 5b, 5c is connected and provided in the upper part between this support | pillar 3 and the support | pillar 4. One end of the optical fiber 6 is laid from the upper surface of the lower flange 5d on the near side in the girder 5a to the upper surfaces of the lower flanges 5e and 5f of the girder 5b, 5c, and the other end of the optical fiber 6 is a strain / loss integrated type light. It is connected to the pulse tester 7. One end of a cord 8 is connected to the strain / loss integrated optical pulse tester 7 and the other end of the cord 8 is connected to a plug 9. One end of a cord 14 is connected to the plug 9 and the other end of the cord 14 is connected to a power source 10. As an example of the power supply 10, a simple generator may be used because the optical fiber 6 is not affected by electromagnetic induction or noise. One end of a cord 11 is connected to the strain / loss integrated optical pulse tester 7 and the other end of the cord 11 is connected to a monitor 12 as an output means. Further, one end of a cord 13 is connected to the monitor 12 and the other end of the cord 13 is connected to the plug 9. The plug 9 is connected to the power supply 10 via the cord 14.

The optical fiber 6 at the connecting portion 15A between the beam 5c and the beam 5b and at the connecting portion 15B between the beam 5b and the beam 5a is allowed to sag in a tension-free state like several loops. Moreover, when the optical fiber 6 is laid on the upper surfaces of the lower flanges 5f, 5e, and 5d in the girders 5c, 5b, and 5a, the optical fiber 6 is not laid on the splice plate portion of the connecting portion 15A and the connecting portion 15B. Then, a double-faced tape is applied to the upper surface of the lower flange 5e of the beam 5b, that is, the left and right ends in FIG. 8, and the optical fiber 6 is placed on the double-faced tape with a certain tension. Paste to temporarily fix while giving. Then, the temporarily fixed optical fiber 6 is adhered to the entire surface with an adhesive, and then an adhesive tape is stuck on the optical fiber 6 so that the optical fiber 6 is laid on the upper surface of the lower flange 5e.

A second example of this type is disclosed in Japanese Patent Laid-Open No. 2000-292216 shown in FIGS. 13 (a) and 13 (b). This optical fiber sensor 15 has an optical fiber 20 on the stable ground 19 side, which is the monitoring reference side with little possibility of landslide, etc., attached to an optical fiber 18 secured with a surplus length attached to the monitoring object 17 exposed on the slope 16. Is detachably connected via the optical connector 21, so that the optical fiber 18 on the monitoring object 17 side and the optical pulse tester 22 are connected via the optical fiber 20 on the stable ground 19 side. . The optical fiber 18 on the side of the monitoring object 17 stores the extra length in a sensor unit 23 attached to the rock that is the monitoring object 17 exposed on the slope 16, and the optical connector 21 drawn out from the sensor unit 23 is Removably connected to the optical fiber 20 on the stable ground 19 side. The sensor unit 23 winds and absorbs the extra length of the optical fiber 18 around a reel 23 a attached to the rock that is the monitoring object 17. The optical fiber 20 on the stable ground 19 side is connected to the optical fiber 18 on the monitored object 17 side via an optical connector 21 and is fixed to the stable ground 19 side near the monitored object 17 by an anchor bolt 24. Yes. The optical fiber 18 on the monitoring object 17 side is kept so as not to be pulled out from the sensor unit 23, and is connected between the sensor unit 23 and the anchor bolt 24 by the optical connector 21 and is tensioned linearly.

A third example of this type is disclosed in Japanese Patent Laid-Open No. 2000-258135 shown in FIGS. To explain this, 25 is a river bank, 26 is a river, and 27 is an optical fiber sensor. The optical fiber sensor 27 includes an optical cable 27a that is a long optical fiber that extends along the longitudinal direction of the river bank 26, and a plurality of sensing units 27b that are continuously provided in the longitudinal direction of the optical cable 27a. It is configured with. The sensing unit 27b is continuously disposed without any gap while being in contact with each other along the longitudinal direction of the optical cable 27a, but may be disposed only at a necessary portion. An optical pulse tester 28 is connected to the optical fiber accommodated in the optical cable 27a, and test light can be incident from the optical pulse tester 28. As shown in FIG. 10 (b), the optical cable 27a has a single-core optical fiber core 27d housed in a resin jacket 27c such as PVC (polyvinyl chloride), and further, the jacket 27c and the optical fiber. A tensile strength body 27e is accommodated between the core wire 27d. Here, the optical cable 27a does not have a tension member that is generally used for a normal outdoor laying optical cable, but depends only on the fibrous strength member 27e, and is used for general outdoor laying. Elongation strain is easily applied compared to optical cables. A material having excellent waterproofness and durability is applied as the outer cover 27c.

A fourth example of this type is shown in FIG. If this is demonstrated, 29 is a planar sensor as a planar optical fiber sensor. The planar sensor 29 is integrally attached and fixed to the surface of the concrete structure with an adhesive. A signal from the planar sensor 29 is connected to an optical fiber communication network 31 via a connector storage box 30, and this optical fiber communication network 31 is installed at a site A at regular intervals, for example, several times a year. (Brillouin Optical Time Domain Reflectometer) is connected to the measuring instrument 32. At the site A, a generator 33 and a personal computer (PC) 34 are provided, and the components are connected to the BOTDR measuring instrument 32. Then, the strain distribution of the concrete structure is measured, the data obtained by the BOTDR measuring instrument 32 and the like is observed as time-series data, and the progress of damage of the concrete structure is predicted from the change in the data. This system configuration functions as an off-line system, and after installation of the surface sensor 29 on a concrete structure, there is a feature that no equipment such as a power source is required and maintenance is free.
In addition, although it can also be set as the structure functioned as an on-line system, in that case, the BOX and equipment which accommodate the BOTDR measuring device 32 grade | etc., In the site A are needed.
Another conventional technique is an apparatus or method that uses an electric wire or the like and has an ON / OFF function depending on the state of energization and cutting of the material by movement due to displacement of the structure.
Japanese Patent Laid-Open No. 2002-90233 Japanese Patent Laid-Open No. 2000-292216 Japanese Patent Laid-Open No. 2000-258135

Since the conventional technique has the above-described configuration, the following problems existed.
That is, according to the first example in the prior art, the bridge 2 having a plurality of connecting portions 15B, 15A at appropriate intervals between the full-length beams 5a, 5b, 5c from one end to the other end. When measuring the strain distribution, the construction method in which the optical fiber 6 is not laid in the connecting portions 15B and 15A and the state is stretched in a tension-free state, or the full length girder 5a from one end to the other end other than the connecting portions 15B and 15A. 5b and 5c need to be constructed with a certain tension applied, and the construction method for girder displacement monitoring is complicated, and the number of installation steps for various facilities on the site is greatly increased. There was a point.

In addition, according to the second example in the prior art, the displacement and strain of the monitoring object 17 of the earth and sand and the rock mass are measured, and the dangerous part such as the rock mass collapse and the slope collapse is constantly monitored to predict a disaster phenomenon. However, it is difficult to apply the technology as it is to the girder displacement monitoring device or system.

Further, according to the third example in the prior art, it is necessary to separately provide a moving part and a displacement amount amplifying part of the river bank 25 in the river bank 25, and the optical cable 27a includes the jacket 27c, There is a bottleneck that cannot be implemented without using a waterproof and highly durable cable that has a complicated structure in the core portion 27d and is different from the optical cable for general outdoor use. There was a problem that it could not be applied.

Also, according to the fourth example in the prior art, it takes time to access the site and analyze data for concrete structures, especially for girders, at all times or during disasters such as earthquakes and emergency inspections. In addition, it was impossible to accurately and quickly grasp the amount of movement, and the construction of the girder displacement monitoring system became expensive, and many problems remained in practice.
In addition, in order to improve the accuracy of the girder displacement, it is necessary to bring the displacement sensor unit and the data measuring device close to each other, and further, equipment for storing the measuring device related to the girder displacement at the site A is necessary, and maintenance costs and construction There was a problem that the cost increased.
In addition, in order to grasp the girder displacement of a structure in the range of, for example, about 30 km during an earthquake, it is necessary for the person in charge of the structure to go directly to the site and check the girder displacement. In the event of an earthquake, there is a problem that it is almost impossible to know the displacement between two points of two members of a structure in a timely manner, such as a human problem or a problem of transportation to the target structure. was there.

The present invention uses a two-point displacement meter configured with a unique structure and installed at one point or the other point, and a BOTDR measuring instrument connected to the two-point displacement meter, so that it is always or during an earthquake. Providing a two-point displacement meter using an optical fiber and a method for remotely monitoring the displacement between two points using an optical fiber that can quickly and properly detect the displacement of a concrete structure, such as a girder, at a predetermined remote location in a disaster. The purpose of this is to establish the following configuration and means.

That is, according to the first aspect of the present invention, the optical fiber winding is a rotatable optical fiber winding that measures a displacement between two points on the other side and includes a plurality of or a plurality of pulleys configured in a plurality of rows. A rotating member, an optical fiber fixing jig connected to one side of the optical fiber wound around the optical fiber winding member, and a displacement / load converting member connected to the other side of the optical fiber are accommodated inside. Thus, one side of the optical fiber is connected to a BOTDR measuring instrument.

According to a second aspect of the present invention, in the first aspect of the invention, the two-point displacement meter is configured as a box-shaped case, and the optical fiber fixing jig and the plurality of rows are arranged on an inner bottom surface thereof. A rotatable optical fiber winding member composed of a plurality of pulleys or a plurality of pulleys, and the displacement / load conversion member are fixed.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the displacement / load conversion member is constituted by a coil spring.

According to the invention described in claim 4, the displacement between the other two points is measured, and is installed at one point, and can be rotated by a plurality of or a plurality of pulleys configured in a plurality of rows. An optical fiber winding member, an optical fiber fixing jig connecting one side of the optical fiber wound around the optical fiber winding member, and a displacement / load converting member connecting the other side of the optical fiber; And one side of the optical fiber is connected to a BOTDR measuring instrument, and a lead wire connected to the displacement / load conversion member is fixed to an angle arranged at the other point.

According to a fifth aspect of the invention, in the first, second, third or fourth aspect of the invention, a tension is applied in advance when the optical fiber is installed.

According to the invention described in claim 6, it is installed on the upper surface of the bridge pier disposed below one of the other girders, and is rotatable by a plurality of or a plurality of pulleys configured in a plurality of rows. An optical fiber winding member, an optical fiber fixing jig connecting one side of the optical fiber wound around the optical fiber winding member, and a displacement / load converting member connecting the other side of the optical fiber; The one side of the optical fiber is connected to a BOTDR measuring instrument, and the lead wire connected to the displacement / load conversion member is fixed to an angle fixed to the lower surface of the girder. To do.

According to the seventh aspect of the present invention, a constant load spring member for measuring a girder displacement between the other two points and winding a lead wire for transmitting the girder displacement, and the constant load spring A displacement / load conversion member for connecting a lead wire from the member and converting a girder displacement into a load, and an optical fiber at one end and the other end are stretched and wound based on the load generated on the displacement / load conversion member; A rotatable light comprising a tension generating member in which the optical fibers at the one end and the other end are connected to a network communication network, and a plurality of or a plurality of pulleys that are wound around the optical fiber and configured in a plurality of rows. And a fiber winding member.

According to the eighth aspect of the present invention, a constant load spring member for measuring a girder displacement between the other two points and winding a lead wire for transmitting the girder displacement, and the constant load spring A displacement / load conversion member for connecting a lead wire from the member and converting a girder displacement into a load, and an optical fiber at one end and the other end are stretched and wound based on the load generated on the displacement / load conversion member; A rotatable light comprising a tension generating member in which the optical fibers at the one end and the other end are connected to a network communication network, and a plurality of or a plurality of pulleys that are wound around the optical fiber and configured in a plurality of rows. A fiber winding member, a box-shaped case having the constant load spring member, a displacement / load conversion member, a tension generating member, and an optical fiber winding member, and a wall portion of the box-shaped case, Arranged before and after the constant load spring member Is characterized by comprising a said lead wire pull-out member for winding the lead wire.

According to a ninth aspect of the invention, in the eighth aspect of the invention, the lead wire lead-out member is connected to both ends of a rotating shaft that penetrates the wall portion of the box-shaped case, and the lead wire is connected to the lead wire. It has a pulley disposed inside and outside a box-shaped case for tensioning and winding, and an oil seal member surrounded by the rotation shaft.

According to the invention of claim 10, a rotatable optical fiber winding member that measures a displacement between two points on the other side and includes a plurality or a plurality of pulleys configured in a plurality of rows. And an optical fiber fixing jig connected to one side of the optical fiber wound around the optical fiber winding member, and a displacement / load conversion member connected to the other side of the optical fiber. Therefore, the two-point displacement remote monitoring by the optical fiber connected to the existing optical fiber network communication network installed in each structure with the two-point displacement meter formed by connecting one side of the optical fiber to the BOTDR measuring instrument Features method.

The two-point displacement meter using an optical fiber and the two-point displacement remote monitoring method using an optical fiber according to the present invention have the following effects because they have the above-described configuration.

That is, according to the first aspect of the present invention, the optical fiber winding is a rotatable optical fiber winding that measures a displacement between two points on the other side and includes a plurality of or a plurality of pulleys configured in a plurality of rows. A rotating member, an optical fiber fixing jig connected to one side of the optical fiber wound around the optical fiber winding member, and a displacement / load converting member connected to the other side of the optical fiber are accommodated inside. Thus, a two-point displacement meter using an optical fiber is provided in which one side of the optical fiber is connected to a BOTDR measuring instrument.
With this configuration, an optical fiber winding member made up of a plurality of pulleys or a plurality of pulleys arranged in a plurality of rows is provided inside the optical fiber, and the length of the optical fiber is required by the optical fiber winding member. It can be installed on the upper surface of each structure, and it can be easily installed on the upper surface of each structure by concentrating it inside a two-point displacement meter that constitutes a small space up to a long length. Regardless, there is an effect that the displacement amount between two points can be detected accurately and quickly.

According to the second aspect of the present invention, the two-point displacement meter is configured as a box-shaped case, and the plurality of or a plurality of the optical fiber fixing jigs formed on the inner bottom surface portion and the plurality of rows are provided. 2. A two-point displacement meter using an optical fiber according to claim 1, wherein a rotatable optical fiber winding member comprising a pulley and the displacement / load converting member are fixed.
Since it was set as such a structure, in addition to the effect of the invention of the said Claim 1, a two-point displacement meter is comprised by the compact box-shaped case, and an optical fiber fixing jig and an optical fiber winding member are set in the inside. Since the components of the displacement / load conversion member such as the coil spring are accommodated, the components can be assembled in a compact manner, and the replacement of the components or members can be facilitated, and the installation man-hour can be greatly reduced.

According to a third aspect of the present invention, there is provided the two-point displacement meter using an optical fiber according to the first or second aspect, wherein the displacement / load converting member is constituted by a coil spring.
Since such a configuration is adopted, the displacement / load conversion member connected to the other side of the optical fiber employs a coil spring having a general-purpose predetermined spring constant, so that it is very easy to implement a two-point displacement meter. There is an effect.

According to the invention described in claim 4, the displacement between the other two points is measured, and is installed at one point, and can be rotated by a plurality of or a plurality of pulleys configured in a plurality of rows. An optical fiber winding member, an optical fiber fixing jig connecting one side of the optical fiber wound around the optical fiber winding member, and a displacement / load converting member connecting the other side of the optical fiber; In which the one side of the optical fiber is connected to a BOTDR measuring instrument, and the lead wire connected to the displacement / load converting member is fixed to an angle arranged at the other point. A fiber-to-point displacement meter is provided.
With this configuration, the other side of the optical fiber is connected to a lead wire fixed to an angle via a displacement / load conversion member on the lower surface of the structure, so that the optical fiber is protected from an external impact or the like. There is an advantage that a highly durable point-to-point displacement meter can be provided by accurately determining and detecting the distortion of the optical fiber and the displacement of the girder even after a long period of time without being protected and possibly damaged.

According to a fifth aspect of the present invention, there is provided a two-point displacement meter using an optical fiber according to the first, second, third or fourth aspect, wherein tension is applied in advance when the optical fiber is installed.
With such a configuration, a plurality of or many pulleys and a coil spring as a displacement / load conversion member can be used to apply tension between the members in advance, so that the displacement can be accommodated in the tension direction and the compression direction. There is an effect of effectively using the displacement between two points.

According to the invention described in claim 6, it is installed on the upper surface of the bridge pier disposed below one of the other girders, and is rotatable by a plurality of or a plurality of pulleys configured in a plurality of rows. An optical fiber winding member, an optical fiber fixing jig connecting one side of the optical fiber wound around the optical fiber winding member, and a displacement / load converting member connecting the other side of the optical fiber; The one side of the optical fiber is connected to a BOTDR measuring instrument, and the lead wire connected to the displacement / load conversion member is fixed to an angle fixed to the lower surface of the girder. An optical fiber girder displacement meter is provided.
With such a configuration, a compactly designed two-point displacement meter is used as a girder displacement meter, and one or the other girder displacement or pier displacement can be detected from the field at any time during a normal or disaster such as an earthquake. An optical fiber girder displacement meter that can be monitored in real time with a BOTDR measuring instrument and other related products that measure strain generated in an optical fiber installed at a predetermined remote location, and can accurately and quickly grasp the amount of digit movement. There is an effect to provide.

According to the seventh aspect of the present invention, a constant load spring member for measuring a girder displacement between the other two points and winding a lead wire for transmitting the girder displacement, and the constant load spring A displacement / load conversion member for connecting a lead wire from the member and converting a girder displacement into a load, and an optical fiber at one end and the other end are stretched and wound based on the load generated on the displacement / load conversion member; A rotatable light comprising a tension generating member in which the optical fibers at the one end and the other end are connected to a network communication network, and a plurality of or a plurality of pulleys that are wound around the optical fiber and configured in a plurality of rows. A two-point displacement meter using an optical fiber characterized by comprising a fiber winding member.
With such a configuration, a constant load spring member and a tension generating member are provided, so that the girder displacement based on noise is prevented and transmitted without holding the lead wire tension at a constant load and accurately transmitting the girder displacement. Since the optical fiber can be uniformly stretched by the optical fiber winding member, it is possible to provide a high-quality two-point displacement meter.

According to the eighth aspect of the present invention, a constant load spring member for measuring a girder displacement between the other two points and winding a lead wire for transmitting the girder displacement, and the constant load spring A displacement / load conversion member for connecting a lead wire from the member and converting a girder displacement into a load, and an optical fiber at one end and the other end are stretched and wound based on the load generated on the displacement / load conversion member; A rotatable light comprising a tension generating member in which the optical fibers at the one end and the other end are connected to a network communication network, and a plurality of or a plurality of pulleys that are wound around the optical fiber and configured in a plurality of rows. A fiber winding member, a box-shaped case having the constant load spring member, a displacement / load conversion member, a tension generating member, and an optical fiber winding member, and a wall portion of the box-shaped case, Arranged before and after the constant load spring member It is to provide a point-to-point displacement meter by the optical fiber, characterized by comprising a said lead wire pull-out member for winding the lead wire.
With such a configuration, in addition to the effect of the invention according to claim 7, in addition to facilitating lead wire drawing, the two-point displacement meter is configured in a compact box-shaped case and has a constant load inside. Since each component of the displacement / load conversion member such as a spring member, an optical fiber winding member and a coil spring, and a tension generating member are accommodated, each component can be assembled in a compact manner, and the replacement of components or members can be facilitated. There is an effect of greatly reducing the man-hours.

According to the ninth aspect of the present invention, the lead wire lead-out member is connected to both ends of the rotating shaft that penetrates the wall portion of the box-shaped case, and the box-shaped case inside and outside that stretches and winds the lead wire. 9. An optical fiber two-point displacement meter according to claim 8, further comprising an oil seal member surrounded by the pulley and an oil seal member surrounded by the rotation shaft.
With such a configuration, in addition to the effect of the invention according to claim 8, the two-point displacement meter improves its confidentiality and durability in a bad external environment such as wind and rain and vibration, and has a long service life. As an instrument, it has the effect of improving reliability.

According to the invention of claim 10, a rotatable optical fiber winding member that measures a displacement between two points on the other side and includes a plurality or a plurality of pulleys configured in a plurality of rows. And an optical fiber fixing jig connected to one side of the optical fiber wound around the optical fiber winding member, and a displacement / load conversion member connected to the other side of the optical fiber. A two-point displacement meter formed by connecting one side of the optical fiber to a BOTDR measuring instrument is connected to an existing optical fiber network communication network installed in each structure. A point-to-point displacement remote monitoring method is provided.
With such a configuration, especially in the event of a disaster such as an earthquake, for example, about 20 (km) to 30 (km) using, for example, an information BOX of an optical fiber network communication network laid along a national road. Connect a plurality of bridges and a BOTDR measuring instrument via an optical switch installed in a remote road office at a certain distance, and connect the optical fiber for measuring displacement and strain between two points by optical fiber in series with the displacement meter. It is possible to configure a method for connecting and remotely monitoring the distortion of the structure, and the effect of automatically monitoring the displacement of the structure between two points or between multiple or multiple points with one optical fiber without the need for power supply equipment There is. In addition, in the event of a disaster such as an earthquake, there is an effect of providing a monitoring system in which the staff in charge does not go directly to a structure at a long distance and can intensively grasp the displacement between two points of the structure.

DESCRIPTION OF EMBODIMENTS Embodiments of a two-point displacement meter using an optical fiber and a two-point displacement remote monitoring method using an optical fiber according to the present invention will be described below in detail with reference to the accompanying drawings.

1 to 6 are examples showing an embodiment of a two-point displacement meter using an optical fiber and a two-point displacement remote monitoring method using an optical fiber according to the present invention. FIG. 1 shows a civil engineering / building structure. FIG. 2 is a schematic diagram showing an arrangement state of a two-point displacement meter using an optical fiber that detects a displacement between two points, and FIG. 2 is a configuration diagram showing each component housed in the two-point displacement meter, FIG. 3 is a characteristic diagram of the load (gf) with respect to strain (μ) of the optical fiber according to the present invention, and FIG. 4 is an optical fiber characteristic of the load (gf) with respect to strain (μ) of the optical fiber according to the present invention. FIG. 5 is a system schematic diagram showing a method of detecting displacement of a structure with a BOTDR measuring instrument via a network communication network by a two-point displacement meter using an optical fiber according to the present invention installed in each structure. 6 is a two-point displacement monitoring system shown in FIG. It is a structure schematic diagram which shows the internal structure of a 2-point displacement meter.

FIG. 1 is an example showing an installation state of a two-point displacement meter using an optical fiber according to the present invention, and shows an example of detecting displacement of a structure such as a girder or a bridge pier. Reference numeral 35 denotes one digit of a civil engineering / building structure such as a concrete structure. Reference numeral 36 denotes the other girder of a civil engineering / building structure such as a concrete structure. An abutment or pier 37 is disposed at a lower position between the one girder 35 and the other girder 36. The pier 37 may be formed of a frame. The bridge pier 37 has a two-point displacement meter 38 disposed on the upper surface thereof, and as shown in FIG. 2, one side and the other side optical fibers 39 and 40 having a strain sensor function are drawn out from the two-point displacement meter 38. The two-point displacement meter 38 in this embodiment has a function as a digit displacement meter.

Further, the two-point displacement meter 38 is housed inside, for example, installed on the upper surface 37a of the pier 37 and connected to the optical fiber 40 on the other side and having the properties of an elastic member shown in FIG. The load converting member 41 includes, for example, a spring, preferably a coil spring (hereinafter simply referred to as “spring”), and the lead wire 42 made of a steel wire or the like connected to the displacement / load converting member 41 is displaced between the two points. The angle is fixed from the total 38 and fixed to the lower surface 36a of the other beam 36. Incidentally, 35a is the lower surface of one girder 35.

Here, as shown in FIG. 2, the two-point displacement meter 38 has two or three rows, that is, in this embodiment, each of the six rows formed in a disk shape and .., 45b, 45b, etc. are combined with the other pulleys 45a, 45a,..., 45b, 45b, and the like, and the same light integrated with the optical fiber 39 on one side and the optical fiber 40 on the other side. An optical fiber 45c formed of a fiber and wound between the pulleys 45a and 45b; an optical fiber fixing jig 45d having one end connected to the one optical fiber 39 and the other end connected to the optical fiber 45c; A displacement / load conversion member 41 made of a coil spring or the like connected to a connection point between the optical fiber 45c and the optical fiber 40 on the other side.
The one and other pulleys 45a and 45b may be in a single row, three rows, four rows, or the like, and more than six may be arranged between the front end and the rear end.

The one pulley 45a, 45a,... And the other pulley 45b, 45b,... Are pivotally mounted so that their shaft centers pass through one and the other shaft rods 45e, 45f and have a mutual width. . The front end 45e1 and the rear end 45e2 of the one shaft rod 45e and the front end 45f1 and the rear end 45f2 of the other shaft rod 45f are respectively provided with two leg portions 45g1, 45g2, 45h1, and 45h2, and the one and the other pulleys 45a. ..., 45b ... are rotatably supported. The one and the other pulleys 45a, 45a,..., 45b, 45b... Have, for example, substantially V-shaped or recessed grooves formed in the outer periphery thereof, and the optical fibers 45c are alternately arranged in the grooves. That is, it is suspended by reciprocating from one pulley 45a to the other pulley 45b.

Since the optical fiber 45c is configured as described above, the optical fiber 45c can obtain a distance corresponding to six of the pulleys 45a and 45b in addition to the distance between the pulley 45a and the pulley 45b. Even when the two-point displacement meter 38 is constituted by a small box-shaped case, the relatively long optical fiber 45c can be accommodated, and on the other hand, it can be applied to the other one having a long girder length. Can do. The two-point displacement meter 38 is provided with, for example, a base (not shown) on the inner bottom surface or the like, and a plurality or many of the optical fiber fixing jig 45d and a plurality of rows are formed on the top of the base. A rotatable optical fiber winding member 45 made of solid pulleys 45a and 45b and a spring, in particular, a displacement / load conversion member 41 made of a coil spring or the like are mounted.

The lead wire 42 drawn out from the displacement / load converting member 41 such as a spring accommodated in the two-point displacement gauge 38 is locked and fixed to the tightening through hole 43a of the hanging fixing portion 43 of the angle 44 at the other end. Yes. The lead / wire 42 is stretched while securing an appropriate tension by the displacement / load conversion member 41, and the displacement / load conversion member 41 of the two-point displacement meter 38 is appropriately extended, and the optical fiber 45c is Tension is applied in advance when the optical fiber winding member 45 is installed, and the distortion of the optical fibers 39 and 40 on the one side and the other side is properly detected, so that it is between two points of the structure, that is, civil engineering / building structure. For example, the amount of displacement or movement of a concrete structure is measured and detected.

The other side optical fiber 40 is drawn from the two-point displacement meter 38 and connected to an angle 44 fixed to the lower surface 36a of the other side girder 36 as shown in FIG. The one side optical fiber 39 is connected to a so-called BORTD measuring instrument 46. Then, a BOTDR (Brillouin Optical Time Domain Reflectometer) measuring device 46 causes a strain distribution applied between the optical fibers 39 and 40 to enter an optical pulse from one end of the optical fibers 39 and 40, and uses one of the backscattered light. The magnitude of distortion is obtained from the frequency shift of a certain Brillouin scattered light, the distance is obtained from the speed of light and the reception time of the light pulse, and the displacement of the beam and the pier is detected.

The two-point displacement meter 38 requires an optical fiber 45c having a length greater than a predetermined value in order to measure the displacement between two points such as a girder and a bridge pier. That is, if the allowable elongation of the optical fiber 45c is 1.2 (%), it is necessary to extend 10 (m) from a predetermined value in order to measure the displacement of 12 (cm). In order to measure an arbitrary amount of displacement, a means for compensating for the allowable elongation of the optical fiber is required. The compensating means is the displacement / load converting member 41 made of the coil spring or the like, and is connected in series to the optical fiber 45c. Accordingly, the configuration of the two-point displacement meter 38 may be configured so as not to include the above-described one and other pulleys 45a, 45b, 45b, the optical fiber winding member 45, and the like.

The operation | movement etc. based on embodiment of the two-point displacement meter by the optical fiber which concerns on this invention mentioned above are demonstrated.

A two-point displacement meter using an optical fiber according to the present invention includes a BOTDR measuring instrument 46 for measuring a strain distribution between optical fibers 39 and 40 serving as a sensor on one side or the other side. It is converted into force by a displacement / load converting member 41 (spring), directly applied between the optical fibers 39, 40, and the distortion generated between the one or other optical fibers 39, 40 is measured. This is a technique for detecting the displacement between two points of the structure.
Then, as shown in FIG. 2, one long side or the other side for measuring the girder distortion on one long optical fiber 45c wound around the optical fiber winding member 45 installed in the two-point displacement meter 38. The optical fibers 39 and 40 on the side are connected in series, and displacements and strains at a plurality of locations of the structure at one point, the other point, for example, the girders 35 and 36 and the pier 37 can be measured simultaneously.

Next, the relationship between the load (gf) and strain (μ) applied between the optical fibers 39 and 40 on the one side or the other side will be described. FIG. 3 shows that the diameter of the strand is 0.25 (mm), It is a characteristic view which shows the relationship between the load Y (gf) applied between the optical fibers 39 and 40 on the one side or the other side in the UV coated wire, and the strain X (μ). This characteristic diagram shows the measurement results in the range of −20 (° C.) to 60 (° C.), and equation (1) is established.
That is, Y = 0.106X (1)
When converted into the load Y (gf) that applies the displacement of one of the other girders 35 and 36 in the formula (1) and added between the optical fibers 39 and 40 on the one side or the other side, the BOTDR measuring instrument 46 , The displacement of one or the other girder 45, 46 or the pier 37 can be measured.

Further, the relationship between the load (gf) applied between the optical fibers 39 and 40 on one side or the other side and the girder displacement will be described. Generally, the optical fibers 39 and 40 are broken at 20000 (μ) to 30000 (μ). It is said that. Considering the worst case, if the maximum allowable strain of the two-point displacement meter 38, that is, the girder displacement meter is 10000 (μ), the measurement accuracy at the pulse width of 100 (ns) is 30 (by the function of the BOTDR measuring device 46). Since it is μ), 10000/30 = 333, so that displacement of about 300 (mm) with an accuracy of 1 (mm), that is, about 3 (m) with an accuracy of 1 (cm) can be measured.

Considering the structure of the earthquake, that is, the displacement of the girder, a displacement of 30 (cm) is required. When the sensor is between the optical fibers 39 and 40, if the allowable strain is 10,000 (μ), the displacement is 30 (cm). In order to obtain the displacement, it is necessary to use an optical fiber having a length of about 30 (m) between the optical fibers 39 and 40. There is a method in which a spring as the displacement / load conversion member 41 is interposed in the optical fibers 39 and 40. For example, as shown in FIG. 4, the elongation of the spring necessary for measuring the displacement of the beam displacement 30 (cm) is 10 (m) × 10000 (μ) = 0.10 (m) by the following calculation. Become. In order to obtain the elongation of 0.10 (m), the load Y applied to the optical fibers 39 and 40 from the above formula (1) becomes Y = 0.106 × 1000 = 1060 (gf). That is, it was found that if 0.10 (m) is pulled at 1060 (g), 10000 (μ) of optical fibers 39 and 40 are generated.

Here, the reason why the spring as the displacement / load converting member 41 is interposed in the above-described two-point displacement meter 38 is that the strain (μ) between the optical fibers 39 and 40 is the length L (m) of the optical fiber, If the elongation is ΔL (m), it is expressed by μ = ΔL (m) / L (m). If the extension of the lead wire 42 is ignored, the displacement of the girders 35 and 36 and the extension ΔL (m) between the optical fibers 39 and 40 are the same. In order to cope with a large displacement, the length L of the optical fiber is increased. There is a need to. The amount of movement of the girders 35 and 36 is a value obtained by adding the elongation of the spring to the elongation ΔL (m) between the optical fibers 39 and 40. By changing the spring constant, the strain (μ) between the optical fibers 39 and 40 can be kept constant to cope with an arbitrary displacement. Further, the displacement in the contracting direction between the optical fibers 39 and 40 can be dealt with by setting the position where tension is applied in advance to 0 point.

The case where the displacement of the girders 35 and 36 is directly received by the optical fibers 39 and 40 and the case where a spring is interposed are described.
(1) When receiving the displacement directly, if the extension of the optical fibers 39 and 40 is 1 (m), the extension of the optical fiber can correspond to a displacement of ± 5 (mm) from the above equation. Assuming that the required movement amount of the girders 35 and 36 is ± 150 (mm), the elongation of the optical fibers 39 and 40 is ΔL = 300 (mm), and the extension of the optical fibers 39 and 40 requires 30 (m). Become.
(2) When a spring is interposed between the girders 35 and 36 and the optical fibers 39 and 40, the optical fibers 39 and 40 are not distorted by 10,000 (μ) or more regardless of the extension of the optical fibers 39 and 40. By selecting such a spring constant, it is possible to cope with an arbitrary displacement.

Next, a two-point displacement remote monitoring method using an optical fiber using the existing optical fiber network communication network shown in FIG. 5 as a specific embodiment 1 according to the present invention described above will be described.
Here, FIG. 5 shows an outline of a so-called long-distance monitoring system, which is an apparatus according to the present invention installed at each structure installation point, that is, at three structures B, C, and D in this embodiment. The BOTDR measuring instrument 46 connected to the existing optical fiber network communication network 51 in series with the optical fibers 39 and 40 drawn from the point-to-point displacement meter 38 and installed at a remote place, the above structures B, C and D The displacement of is detected all at once. Further, in this embodiment, after the optical fibers 39 and 40 on one side or the other side are installed in the girders 35 and 36, the power supply equipment is not required at the installation sites B to E, and the maintenance-free state is brought about.
In FIG. 5, reference numeral 37 denotes a pier.

Next, the internal configuration and operation of the two-point displacement meter 38 shown in FIG. 6 will be described based on the first embodiment shown in FIG.
As shown in FIG. 6, the two-point displacement meter 38 has two or three rows, that is, in this embodiment, six one and other pulleys 45a each having a disc shape. 45a... And 45b, 45b... Are composed of optical fiber winding members 45 configured in two rows, the same optical fiber integrated with the one side optical fiber 39 and the other side optical fiber 40, and An optical fiber 45c wound between the pulleys 45a and 45b, an optical fiber fixing jig 45d having one end connected to the optical fiber 39 on one side and the other end connected to the optical fiber 45c, and the optical fiber 45c It is comprised with the displacement and load conversion member 41 which consists of a coil spring etc. which were connected to the connection point of the optical fiber 40 of the other side.
Further, the above-described optical fiber 39 on the one side, optical fiber 40 on the other side, and optical fiber 45c are one continuous, and are constituted by a single optical fiber.
The one and other pulleys 45a and 45b may be in a single row, three rows, four rows, or the like, and more than six may be arranged between the front end and the rear end.

The one pulley 45a, 45a,... And the other pulley 45b, 45b,... Are pivotally mounted so that their shaft centers pass through one and the other shaft rods 45e, 45f and have a mutual width. . The front end 45e1 and the rear end 45e2 of the one shaft rod 45e and the front end 45f1 and the rear end 45f2 of the other shaft rod 45f are respectively provided with two leg portions 45g1, 45g2, 45h1, and 45h2, and the one and the other pulleys 45a. ..., 45b ... are rotatably supported. The one and the other pulleys 45a, 45a,..., 45b, 45b... Have, for example, substantially V-shaped or recessed grooves formed in the outer periphery thereof, and the optical fibers 45c are alternately arranged in the grooves. That is, it is suspended by reciprocating from one pulley 45a to the other pulley 45b.

Since the optical fiber 45c is configured as described above, the optical fiber 45c can obtain a distance corresponding to six of the pulleys 45a and 45b in addition to the distance between the pulley 45a and the pulley 45b. Even when the two-point displacement meter 38 is constituted by a small box-shaped case, the relatively long optical fiber 45c can be accommodated, and on the other hand, it can be applied to the other one having a long girder length. Can do. The two-point displacement meter 38 has, for example, a base installed on the bottom surface of the inside, and a plurality of or a plurality of solid pulleys 45a composed of the optical fiber fixing jig 45d and a plurality of rows on the top surface of the base. A rotatable optical fiber winding member 45 made of 45b and a displacement / load converting member 41 made of a spring, particularly a coil spring or the like are mounted.

The lead wire 42 drawn out from the displacement / load converting member 41 such as a spring accommodated in the two-point displacement gauge 38 is locked and fixed to the tightening through hole 43a of the hanging fixing portion 43 of the angle 44 at the other end. Yes.
The lead / wire 42 is stretched while securing an appropriate tension by the displacement / load conversion member 41, and the displacement / load conversion member 41 of the two-point displacement meter 38 is appropriately extended. Tension is applied in advance when installing the optical fiber winding member 45 on the optical fiber winding member 45 so that the distortion of the optical fibers 39 and 40 on the one side and the other side can be properly detected, and between two points of the structure, that is, civil engineering / architecture Measure and detect the amount of displacement or movement of a structure, such as a concrete structure. The other optical fiber 40 is connected to a connection point P between the other end of the optical fiber 45c wound around the optical fiber winding member 45 and the displacement / load conversion member 41, and an existing optical fiber network. Connect to the communication network 51.

In addition, as shown in FIG. 5, the optical fiber 40 on the other side of each of the two-point displacement gauges 38 installed at the respective structure installation points B, C, D is connected via the optical fiber network communication network 51. Are sequentially connected in series with the optical fiber 39 on one side of the next stage. Then, the optical fiber 39 on one side of the final two-point displacement meter 38 is connected to a so-called BOTDR measuring device 46 via the optical fiber network communication network 51.
Other constituent members are substantially the same as those shown in FIG.

Next, a second embodiment which is an application example of the two-point displacement meter in the two-point displacement remote monitoring system according to the present invention shown in FIG. 6 will be described.
The feature point of the two-point displacement meter 38A according to the second embodiment is to measure the girder displacement between the other two points, as is apparent from the schematic configuration diagram shown in FIG. A constant load spring member 53 wound with a lead wire 42 to be transmitted, a displacement / load conversion member 41 that connects the lead wire 42 from the constant load spring member 53 and converts a digit displacement into a load, and the displacement / load Based on the load generated in the conversion member 41, one end and the other end of the optical fiber 45c are stretched and wound, and the one side and the other side optical fibers 39, 40 are connected to the network communication networks 51, 51. 52 and the optical fiber 45c that is continuous with the optical fibers 39 and 40 on the one side and the other side, and is rotatable by a plurality or a plurality of pulleys configured in a plurality of rows. Optical fiber winding In that a wood 45.

A second embodiment of the two-point displacement meter in the two-point displacement remote monitoring system according to the present invention will be described with reference to FIG. Is formed by combining nine one and other pulleys 45a, 45a,..., 45b, 45b... Formed in a disc shape, and the one-side optical fiber 39 and The optical fiber 45c is composed of the same optical fiber integrated with the other optical fiber 40 and is wound between the pulleys 45a and 45b, and the optical fiber 39 and the optical fiber 40 are the optical fiber winding member 45. Are fixed by a tension generating member 52 and connected to external network communication networks 51 and 51, respectively. On the other hand, a civil engineering / building structure between two points, for example, a lead wire 42 for transmitting the displacement of one side of the other is wound around the constant load spring member 53, and the lead wire 42 loads the displacement of the digit. It connects with the other end of the displacement and load conversion member 41 which converts into. One end of the displacement / load converting member 41 connects a lead wire 42a of the same type or different from the lead wire 42 to the tension generating member 52. Then, the tension generating member 52 is rotationally driven to apply tension to the optical fiber 45c, and a displacement signal of the structure between the two points, that is, a digit displacement signal is transmitted through the network communication networks 51 and 51, Measurement is performed by the BOTDR measuring instrument 46.

In FIG. 7, a dummy pulley and an oil seal member, which will be described later, provided in the configuration of the second embodiment of the two-point displacement meter 38A are omitted.
The one and other pulleys 45a and 45b may be in a single row, three rows, four rows, or the like, and a multiplicity other than nine may be arranged between the front end and the rear end.

The one pulley 45a, 45a,... And the other pulley 45b, 45b,... Have shafts that pass through the shaft rods 45e, 45f and have a width between them so that they can rotate. The front end 45e1 and the rear end 45e2 of the shaft rod 45e and the front end 45f1 and the rear end 45f2 of the shaft rod 45f are each provided with two leg portions or bearing members 45g1, 45g2, 45h1, 45h2, and the one and other pulleys 45a,. 45b are rotatably supported. The one and the other pulleys 45a, 45a,..., 45b, 45b... Have, for example, substantially V-shaped or recessed grooves formed in the outer periphery thereof, and the optical fibers 45c are alternately arranged in the grooves. That is, it is suspended by reciprocating from one pulley 45a to the other pulley 45b.

Since the optical fiber 45c is configured as described above, the optical fiber 45c can obtain a distance corresponding to nine of the one pulley 45a, the other pulley 45b, in addition to the distance between the one pulley 45a and the other pulley 45b. Even when the two-point displacement meter 38A is formed of a small box-like case, the relatively long optical fiber 45c can be accommodated, and on the other hand, it can be applied to the other one having a long girder length. Can do.

Next, FIG. 8 shows a specific structural example of the configuration shown in Example 2 of the two-point displacement meter 38A in the two-point displacement remote monitoring system according to the present invention shown in FIG. 7, and this will be described. .
FIG. 8 is a structural example of the two-point displacement meter 38A in the second embodiment, and is a plan view in which the whole is sectioned in the horizontal direction.

Reference numeral 54 denotes a substantially rectangular box-shaped case, for example, which houses the constituent members of the two-point displacement meter 38A. The box-shaped case 54 is formed of, for example, a stainless steel (SUS304) material, and includes a component member or an internal component housed therein via a single or a plurality of pipes 54b penetrating through a predetermined portion of the wall portion 54a. Nitrogen gas as anti-condensation gas is sealed to prevent condensation on the wall surface. The pipe 54b is provided with a control switching valve or cock 54c to control the amount of nitrogen gas filled according to the design specifications.

A lead wire lead member 55 is attached to a predetermined portion of the wall portion 54a of the box-shaped case 54. The lead wire lead-out member 55 includes a rotation shaft 55a penetrating the wall portion 54a of the box-shaped case 54. Both ends of the rotation shaft 55a, that is, the inner end 55a1 and the outer end 55a2 of the box-shaped case 54 are provided. Are connected to one and the other pulleys 55b and 55b as the winding mechanism of the lead wire 42, respectively. The lead wire lead-out member 55 includes an oil seal member 55c. The lead wire lead member 55 is surrounded by a bearing on the rotary shaft 55a and is pressed against and fixed to the wall portion 54a through an O-ring 55d having a sealing function. ing. The oil seal member 55c is formed with recesses or recesses 55e and 55f into which the rotary shaft 55a is fitted in the inner wall portion and the outer wall portion of the box-shaped case 54, and an oil sealant is formed in the recesses or recesses 55e and 55f. It is configured by applying or injecting 55 g and 55 g. Since it is configured in this manner, the inside and outside confidentiality of the box-shaped case 54 is completely ensured, and the prevention of condensation in the box-shaped case 54 is given to promote the extension of the life of other components, and high quality A two-point displacement meter 38A can be provided.

The constant load spring member 53 functions, for example, as a filter for holding the tension of the lead wire 42 for transmitting a girder displacement at a certain load or more and at the same time preventing and blocking the displacement other than the girder movement. The lead wire 42 introduced from the lead wire drawing member 55 described above is wound via the direction change pulley 56 and directly connected to the other end of the displacement / load conversion member 41 in the subsequent stage. As shown in FIG. 9, the constant load spring member 53 includes, for example, a lead wire winding portion 53 </ b> A having a plurality of upper and lower steps and a generally cylindrical or columnar body, and a winding portion return mechanism 53 </ b> B. It consists of.

The lead wire winding unit 53A includes, for example, an upper winding unit 53A1 for winding the lead wire 42 introduced from the lead wire drawing member 55 and the direction changing pulley 56, and an upper winding unit 53A1 as illustrated. A lower rotation return member fixing portion 53A2 integrally formed in the vertical direction is provided, and one end portion of, for example, a metal plate spring 53C1 having a rotation return function is fixed to the lower rotation return member fixing portion 53A2 with a screw or the like. Further, hooks 53A3 and 53A4 are fixedly arranged at the upper end and the middle position of the lead wire winding portion 53A, that is, the connecting portion between the upper winding portion 53A1 and the lower rotation returning member fixing portion 53A2, and the wound lead wire 42 is detached. I'm trying to prevent it. The winding part return mechanism 53B is disposed adjacent to the lead wire winding part 53A, and is formed of, for example, a bobbin-like winding body as shown in the figure, and the metal plate spring 53C as a rotation return part. It has a cylindrical or columnar leaf spring winding portion 53B1 with its end portions wound and fixed, and flanges 53B2 and 53B3 formed on the upper and lower ends of the leaf spring winding portion 53B1.

Further, the lead wire winding portion 53A and the winding return mechanism 53B are pivotally attached to vertical shafts 53A5 and 53B4 which are erected and fixed on a base 54e laid on the bottom surface 54d of the box-shaped case 54. .
Thus, as the lead wire winding portion 53A winds and pulls the lead wire 42, the metal leaf spring 53C expands while rotating the leaf spring winding portion 53B1 of the winding portion return mechanism 53B. Alternatively, the lead wire take-up portion 53A is compressed and rotated left or right. Since the metal plate spring 53C always applies a tensile force to the lead wire winding portion 53A, the tension of the lead wire 42 wound around the lead wire winding portion 53A can be maintained at a constant load.
The metal leaf spring 53C may be composed of other parts such as a non-metallic material, a cam, or a small motor.

The displacement / load conversion member 41 includes, for example, a substantially cylindrical container 41a, a container cap 41d fixed to one end and the other end of the container 41a, and an elastic member inserted into the container 41a as illustrated. For example, a spring 41b such as a coil spring, a bracket or a leg for fixing one side and the other side of the container 41a on the base 54e, and bearing members 41c and 41c are provided. One end and the other end of the spring 41b are connected to the lead wire 42 from the constant load spring member 53 and the lead wire 42a connected to the tension generating member 52, respectively.

The displacement / load converting member 41 is a device that converts a displacement between two points, that is, a girder displacement into a load by a spring 41b of the container 41a. For example, based on trial calculation or experiment, the design specification of the spring 41b is a lead wire 42. When the tension is 9.7 (N), a moving pulley (not shown) connected to the spring 41b is provided, the wire diameter is 1.0 (mm), the material is SUS304WPB, and the length is 57. It was found that when the container length was set to 2 (mm) and the container length to 158.2 (mm), the girder displacement could be converted into the load with high conversion efficiency.
Here, if the movable pulley is arranged in the container 41a, the extension of the spring 41b can be shortened, and the displacement / load converting member 41 can be downsized.

As shown in FIG. 10, the tension generating member 52 is, for example, an idler, and is configured by superposing upper, middle and lower pulleys 52a, 52b and 52c on the upper, middle and lower stages. Further, the tension generating member 52 is provided with a vertical shaft 52d erected in the vertical direction on the base 54e, which is a substantially central part of the upper, middle pulleys 52a, 52b and the lower pulley 52c, and the upper pulley 52a, The middle pulley 52b and the lower pulley 52c are pivotally attached to the vertical shaft 52d.

The tension generating member 52 rotates the lower pulley 52c via the lead wire 42a with the load generated on the displacement / load converting member 41, and interlocks with this. The one-side optical fiber 45c1 and the other-side optical fiber 45c2 as the optical fibers 45c fixed to the upper pulley and the middle pulley 52b, respectively, are wound through a direction changing member 52A configured by, for example, a pulley, and the above-described optical fiber winding is performed. This is a device for generating tension in the optical fiber 45c suspended from one pulley 45a of the rotating member 45 and the other pulley 45b. Here, the one-side and other-side optical fibers 45c1 and 45c2 are fixed to the substantially V-shaped or recessed grooves 52a1 and 52b1 of the upper and middle pulleys 52a and 52b with adhesives 52e and 52e made of epoxy resin or the like.

In FIG. 8, the optical fiber 45 has two or three rows, that is, in this embodiment 2, nine one and other pulleys 45a, 45a,. , 45b... Are combined with the optical fiber winding member 45 configured in two rows, the same optical fiber integrated with the one side optical fiber 45c1 and the other side optical fiber 45c2, and between the pulleys 45a and 45b. The optical fiber 45c wound around the optical fiber 45c, the optical fiber 45c1 and the optical fiber 45c2 are led out from the optical fiber winding member 45 and then fixed by the tension generating member 52, and are respectively connected to the external network communication networks 51 and 51. Connected.

As shown in FIG. 10, the one side optical fiber 45c1 and the other side optical fiber 45c2 are integrated into the box-like case by the one side optical fiber 39 and the other side optical fiber 40 through adhesives 52e and 52e. 54 is derived to the outside and connected to the network communication networks 51 and 51, respectively. Here, one optical fiber 39 connected to the tension generating member 52 includes pulleys 45j and 45k fixed to one and the other shaft rods 45e and 45f of the optical fiber winding member 45, and both pulleys 45j. And a packing bar 47a that is suspended from the pulleys 45j and 45k of the dummy optical fiber displacement detecting member 45A constituted by the connecting bar 45m for connecting 45k and is fitted to the wall portion 54a of the box-like case 54 via the pulley 45j and 45k. It is connected to the network communication network 51 through the inside.
The optical fiber 40 on the other side connected to the tension generating member 52 is inserted into the packing member 47 b fitted to the wall portion 54 a of the box-shaped case 54 and connected to the network communication network 51.

Since the distortion signal of the girder displacement is generated by the expansion / contraction action of the optical fiber 45c due to the temperature change of the optical fiber 45c itself or the optical fiber winding member 45 other than the tension due to the girder displacement, an appropriate girder displacement is thus obtained. In order to transmit a signal, the dummy optical fiber displacement detecting member 45A has a function of blocking or canceling a beam displacement signal based on a distortion factor other than the beam displacement.
The one side optical fiber 39, the other side optical fiber 40, the one side optical fiber 45c1, the other side optical fiber 45c2, and the optical fiber 45c described above are a continuous one, and are configured by a single optical fiber. Yes.

Other configurations and operations of the two-point displacement meter 38A according to the second embodiment in the two-point displacement remote monitoring system according to the present invention described above are substantially the same as those of the first embodiment, and the description thereof is omitted. To do.

Next, Embodiment 3 which is an application example of the system for remotely monitoring the displacement between two points according to the present invention will be described.
FIG. 11 is a specific configuration diagram of the remote monitoring system when a structure installation point E is further added in addition to the structure installation points B to D of FIG. This will be described to clarify the third embodiment of the present invention.
As shown in FIG. 11, a road having a predetermined remote location constructed by an optical fiber network communication network 51 at a position of, for example, 30 (km) from the installation point B to E of the displacement monitor between two points, that is, the installation points B to E of the structure. The system which detects the displacement between two points | pieces with the BOTDR measuring instrument 46 with which the office 48 grade | etc., Was equipped, and its related equipment is shown.

The road office 48 includes, for example, a structure such as the BOTDR measuring instrument 46 and a plurality of or many bridges and girders in which two-point displacement meters 38 and 38A are installed between the optical fibers 39 and 40 on one side and the other side. An optical switch 49 connected to the BOTDR measuring instrument 46 and a control personal computer 50 connected to the AC power source and connected to the BOTDR measuring instrument 46 are installed for switching monitoring.

In particular, this is a system showing a method for remotely monitoring the displacement between two points at the time of a disaster such as an earthquake. For example, the light installed in the road office 48 from the optical fiber network communication network 51 laid along the road. Via a switch 49, the displacement between two points of a structure such as a plurality or a large number of bridges and girders is switched and monitored. Further, in this embodiment, after the optical fibers 39 and 40 on one side or the other side are installed in the girders 35 and 36, the power supply equipment is not required at the installation sites B to E, and the maintenance-free state is brought about. The optical switch 49 can automatically switch and monitor the displacement between two or more structures such as a plurality or many bridges and girders 35 and 36.

Next, the operation of the third embodiment of the method for remotely monitoring the displacement between two points using the two-point displacement meter by the optical fiber according to the present invention shown in FIGS. 5 and 11 will be described.

The two-point displacement remote monitoring system has a certain level of optical loss in the optical fibers 39 and 40, the optical fiber network communication network 51, etc. connecting the two-point displacement meters 38 and 38A and the BOTDR measuring device 46 in terms of measurement principle. There is a need to: The transmission loss of the optical fibers 39, 40, the optical fiber network communication network 51, etc. is determined by the extended fusion location, the connector connection location, and the like. Further, the allowable level of transmission loss is determined by the pulse width as the distance resolution sent from the BOTDR measuring instrument 46. It has also been found that a structure within a communication line extension of 20 (km) to 30 (km) with a distance resolution of 11 (m) and 22 (m) can be measured with a single BOTDR measuring instrument 46. The measurement time of the BOTDR measuring instrument 46 differs depending on the measurement condition setting method. As setting conditions related to the measurement time, when the number of additions, frequency sweep argument, etc. are the main factors and normal digit displacement is monitored, for example, the number of additions is 2 ¹⁴ and the number of frequency sweeps is about 40. The measurement is performed in 6 minutes. However, by adjusting these settings, it is possible to monitor the displacement between two points during a disaster such as an earthquake within 2 minutes.

As a system in the remote monitoring method for displacement between two points using an optical fiber according to the present invention, the following embodiments can be further considered. That is, first, a digit displacement measuring system. This is a so-called off-line system. A girder displacement monitoring sensor as a two-point displacement meter is installed in a plurality of girder, they are connected in series with an optical fiber, and a connector is attached to the end. The system is stored in a storage BOX, and when necessary, a measurement device is carried to the site and a connector is connected to perform measurement.
Next is the slope failure monitoring system. This is done by installing a girder displacement monitoring sensor as a two-point displacement meter in a place where there is a possibility of collapse, falling rocks, etc. The prediction system has a feature that remote monitoring is possible by connecting the girder displacement monitoring sensor to an existing optical fiber communication network.

FIG. 2 is an example showing an embodiment of a two-point displacement meter using an optical fiber and a method for remotely monitoring a two-point displacement using an optical fiber according to the present invention, and is an optical fiber that detects a displacement between two points as a concrete structure. It is a schematic diagram which shows the arrangement | positioning state of a point-to-point displacement meter. It is an example which shows embodiment of the two-point displacement meter by the optical fiber and the two-point displacement remote monitoring method by the optical fiber concerning the present invention, Comprising: Each component accommodated in the inside of the above-mentioned two-point displacement meter FIG. It is a characteristic view of the load (gf) with respect to distortion (μ) of the optical fiber according to the present invention. It is an optical fiber strand characteristic view of load (gf) to distortion (μ) of an optical fiber concerning the present invention. 1 is an example showing an embodiment of a two-point displacement meter using an optical fiber and a two-point displacement remote monitoring method using an optical fiber according to the present invention, and the two-point displacement using the optical fiber according to the present invention installed in each structure; It is a system schematic diagram which shows the method of detecting the displacement of a structure with a BOTDR measuring device via a network communication network with a displacement meter. FIG. 6 is a schematic configuration diagram of Example 1 of a two-point displacement meter in the two-point displacement remote monitoring system shown in FIG. 5. It is a structure schematic diagram of Example 2 of the two-point displacement meter in the two-point displacement remote monitoring system which concerns on this invention. FIG. 9 is a horizontal sectional view showing a specific structural example of the second embodiment of the two-point displacement meter in the two-point displacement remote monitoring system according to the present invention shown in FIG. 7. It is a side view which shows an example of the constant load spring member with which the specific structural example of Example 2 of the two-point displacement meter in the two-point displacement remote monitoring system which concerns on this invention shown in FIG. 8 was equipped. It is a side view which shows an example of the tension generation member with which the specific structural example of Example 2 of the two-point displacement meter in the two-point displacement remote monitoring system which concerns on this invention shown in FIG. 8 was equipped. It is an example which shows Example 3 of the two-point displacement remote monitoring method by the optical fiber using the two-point displacement meter by the optical fiber which concerns on this invention, Comprising: It is the two-point displacement meter by the optical fiber installed in each structure It is a block diagram which shows an example of the system which shows the method of monitoring the displacement of each structure in the position distant from the remote place, for example, about 30 (km). It is a block diagram of the digit displacement monitoring system which shows the 1st example in a prior art. It is a monitoring object displacement detection system using the optical fiber sensor which shows the 2nd example in a prior art, Comprising: (a) is a whole block diagram, (b) is the side view to which the monitoring object was expanded. . It is a river dike displacement detection system using an optical fiber sensor showing a third example in the prior art, where (a) is an overall configuration diagram and (b) is a cross-sectional view of an optical cable. It is a whole block diagram of the concrete structure displacement detection system using the planar sensor which shows the 4th example in a prior art.

Explanation of symbols

35 One girder 35a The lower surface 36 of one girder The other girder 36a The lower surface 37 of the other girder 37 Abutment (abutment)
37a Upper surface 38 of bridge pier (abutment) Two-point displacement meter 38A Two-point displacement meter 39 Optical fiber 40 on one side Optical fiber 41 on the other side Displacement / load conversion member 41a Container 41b for displacement / load conversion member Displacement / load conversion Member spring 41c Displacement / load conversion member bracket (leg, bearing member)
42 Lead wire 42a Lead wire 43 Angle hanging fixing portion 43a Angle hanging fixing portion tightening through hole 44 Angle 45 Optical fiber winding member 45a Optical fiber winding member one pulley 45b Optical fiber winding member other pulley 45c Optical fiber winding member optical fiber 45c1 Optical fiber winding member optical fiber one side optical fiber 45c2 Optical fiber winding member optical fiber other side optical fiber 45d Optical fiber winding member optical fiber fixing jig 45e One shaft rod 45e1 of the optical fiber winding member Front end 45e2 of one shaft rod of the optical fiber winding member Rear end 45f of one shaft rod of the optical fiber winding member The other shaft rod 45f1 of the optical fiber winding member Front end 45f2 of the other shaft rod of the fiber winding member Rear end 45 of the other shaft rod of the optical fiber winding member DESCRIPTION OF SYMBOLS 1 Optical fiber winding member leg 45g2 Optical fiber winding member leg 45h1 Optical fiber winding member leg 45h2 Optical fiber winding member leg 45A Dummy optical fiber displacement detection member 45j Dummy optical fiber displacement One pulley 45k of the detecting member 45m of the dummy optical fiber displacement detecting member The other pulley 45m of the dummy optical fiber displacement detecting member connection bar 46 BOTDR measuring instrument 47a Packing member 47b Packing member 48 Road office 49 Optical switch 50 Control personal computer 51 Optical fiber network communication network 52 Tension generating member 52A Direction changing member 52a Tension generating member upper pulley 52b Tension generating member middle pulley 52c Tension generating member lower pulley 52d Tension generating member vertical shaft 52e Tension generating member adhesive 53 Load spring member 53A Heavy spring member lead wire winding portion 53A1 Constant load spring member lead wire winding portion upper winding portion 53A2 Constant load spring member lead wire winding portion Lower rotation return member fixing portion 53A3 Constant load spring member lead鍔 53A4 of the lower rotation return member fixing portion of the wire winding portion 鍔 53B of the lower rotation return member fixing portion of the lead wire winding portion of the constant load spring member Ｂ 53B of the constant load spring member of the constant load spring member Leaf spring winding part 53B2 of the winding part return mechanism Winding part 53B3 of the leaf spring winding part of the winding part return mechanism of the constant load spring member 鍔 53C of the leaf spring winding part of the winding part return mechanism of the constant load spring member Metal plate spring 54 of constant load spring member Box-shaped case 54a Box-shaped case wall 54b Box-shaped case piping 54c Box-shaped case control switching valve (cock)
55 Lead wire drawing member 55a Rotating shaft 55b, 55b of lead wire drawing member One pulley of lead wire drawing member 55c Oil seal member 55d of lead wire drawing member O-ring 55e of lead wire drawing member Recess of lead wire drawing member (Concave)
55f Recess of lead wire lead-out member
55 g Oil sealant for lead wire lead-out member 56 Direction change pulley B to E Installation point of structure

Claims (10)

On the other hand, a displacement between the other two points is measured, and a rotatable optical fiber winding member composed of a plurality of or a plurality of pulleys configured in a plurality of rows, and a winding around the optical fiber winding member. An optical fiber fixing jig connecting one side of the optical fiber mounted and a displacement / load converting member connecting the other side of the optical fiber are housed inside, and one side of the optical fiber is BOTDR A two-point displacement meter using an optical fiber, characterized by being connected to a measuring instrument. The two-point displacement meter is configured as a box-shaped case, and a rotatable optical fiber winding comprising the optical fiber fixing jig on the inner bottom surface thereof and a plurality or a plurality of pulleys configured in a plurality of rows. 2. A two-point displacement meter using an optical fiber according to claim 1, wherein the member and the displacement / load conversion member are fixed. The two-point displacement meter using an optical fiber according to claim 1 or 2, wherein the displacement / load conversion member is constituted by a coil spring. On the other hand, it measures the displacement between the other two points, is installed at one point, and is a rotatable optical fiber winding member comprising a plurality of or a plurality of pulleys configured in a plurality of rows, and the light An optical fiber fixing jig connected to one side of the optical fiber wound around a fiber winding member and a displacement / load converting member connected to the other side of the optical fiber are housed inside, and the light A two-point displacement meter using an optical fiber, wherein one side of the fiber is connected to a BOTDR measuring instrument, and a lead wire connected to the displacement / load converting member is fixed to an angle arranged at the other point. 5. A two-point displacement meter using an optical fiber according to claim 1, wherein a tension is applied in advance when the optical fiber is installed. On the other hand, a rotatable optical fiber winding member which is installed on the upper surface of a bridge pier disposed below between the other girders and is composed of a plurality of or a plurality of pulleys configured in a plurality of rows, and the light An optical fiber fixing jig connected to one side of the optical fiber wound around a fiber winding member and a displacement / load converting member connected to the other side of the optical fiber are housed inside, and the light An optical fiber girder displacement meter in which one side of a fiber is connected to a BOTDR measuring instrument and a lead wire connected to the displacement / load converting member is fixed to an angle fixed to the lower surface of the girder. On the other hand, a girder displacement between the other two points is measured, and a constant load spring member wound with a lead wire for transmitting the girder displacement is connected to a lead wire from the constant load spring member and the girder is connected. A displacement / load conversion member that converts displacement into a load, and an optical fiber at one end and the other end are stretched and wound based on the load generated at the displacement / load conversion member, and the optical fiber at the one end and the other end is networked A tension generating member connected to a communication network; and a rotatable optical fiber winding member that is configured to wind the optical fiber and includes a plurality of or a plurality of pulleys configured in a plurality of rows. A point-to-point displacement meter using an optical fiber. On the other hand, a girder displacement between the other two points is measured, and a constant load spring member wound with a lead wire for transmitting the girder displacement is connected to a lead wire from the constant load spring member and the girder is connected. A displacement / load conversion member that converts displacement into a load, and an optical fiber at one end and the other end are stretched and wound based on the load generated at the displacement / load conversion member, and the optical fiber at the one end and the other end is networked A tension generating member connected to a communication network, a rotatable optical fiber winding member that is wound with the optical fiber and is composed of a plurality of or a plurality of pulleys, and the constant load spring. A box-like case having a member, a displacement / load conversion member, a tension generating member, and an optical fiber winding member, and a wall portion of the box-like case, which are disposed before and after the constant load spring member; Wind the lead wire Between two points displacement meter by the optical fiber, characterized by comprising a said lead wire pull-out member. The lead wire drawing member is connected to both ends of a rotating shaft penetrating the wall portion of the box-shaped case, and is disposed inside and outside the box-shaped case for stretching and winding the lead wire, and the rotating shaft The two-point displacement meter using an optical fiber according to claim 8, further comprising an oil seal member surrounded by the optical fiber. On the other hand, a displacement between the other two points is measured, and a rotatable optical fiber winding member composed of a plurality of or a plurality of pulleys configured in a plurality of rows, and a winding around the optical fiber winding member. An optical fiber fixing jig connecting one side of the optical fiber mounted and a displacement / load converting member connecting the other side of the optical fiber are housed inside, and one side of the optical fiber is BOTDR A point-to-point displacement remote monitoring method using an optical fiber, wherein a point-to-point displacement meter connected to a measuring instrument is connected to an existing optical fiber network communication network installed in each structure.

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