CN105022131B - Sensing optical cable for monitoring leakage of long-distance tunnel/pipeline - Google Patents
Sensing optical cable for monitoring leakage of long-distance tunnel/pipeline Download PDFInfo
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- CN105022131B CN105022131B CN201510472980.XA CN201510472980A CN105022131B CN 105022131 B CN105022131 B CN 105022131B CN 201510472980 A CN201510472980 A CN 201510472980A CN 105022131 B CN105022131 B CN 105022131B
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- leakage
- sensor fibre
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- 238000012544 monitoring process Methods 0.000 title claims abstract description 37
- 230000003287 optical effect Effects 0.000 title claims abstract description 25
- 239000000463 material Substances 0.000 claims abstract description 43
- 239000013307 optical fiber Substances 0.000 claims abstract description 12
- 239000000835 fiber Substances 0.000 claims description 52
- 230000007704 transition Effects 0.000 claims description 22
- 230000008859 change Effects 0.000 claims description 5
- 230000006698 induction Effects 0.000 claims description 4
- 238000010521 absorption reaction Methods 0.000 claims description 2
- 230000008595 infiltration Effects 0.000 claims description 2
- 238000001764 infiltration Methods 0.000 claims description 2
- 238000005516 engineering process Methods 0.000 abstract description 6
- 238000006243 chemical reaction Methods 0.000 abstract description 4
- 230000009286 beneficial effect Effects 0.000 abstract description 3
- 238000013461 design Methods 0.000 abstract description 2
- 238000000253 optical time-domain reflectometry Methods 0.000 description 6
- 238000000034 method Methods 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 230000005540 biological transmission Effects 0.000 description 3
- 238000010276 construction Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 230000007797 corrosion Effects 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 238000005452 bending Methods 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 230000023077 detection of light stimulus Effects 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 230000008832 photodamage Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 239000011150 reinforced concrete Substances 0.000 description 1
- 230000008439 repair process Effects 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 230000001953 sensory effect Effects 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/44—Mechanical structures for providing tensile strength and external protection for fibres, e.g. optical transmission cables
- G02B6/4401—Optical cables
- G02B6/4415—Cables for special applications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M3/00—Investigating fluid-tightness of structures
- G01M3/02—Investigating fluid-tightness of structures by using fluid or vacuum
- G01M3/04—Investigating fluid-tightness of structures by using fluid or vacuum by detecting the presence of fluid at the leakage point
- G01M3/042—Investigating fluid-tightness of structures by using fluid or vacuum by detecting the presence of fluid at the leakage point by using materials which expand, contract, disintegrate, or decompose in contact with a fluid
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Length Measuring Devices By Optical Means (AREA)
- Examining Or Testing Airtightness (AREA)
- Light Guides In General And Applications Therefor (AREA)
Abstract
The invention discloses a sensing optical cable for leakage monitoring of a long-distance tunnel/pipeline, which converts leakage into optical loss of optical fibers through reasonable structural design, and monitors optical loss distribution along the optical fibers by utilizing an Optical Time Domain Reflectometer (OTDR) technology, thereby realizing random leakage monitoring of a long-distance structure. The sensing optical cable comprises the leakage-deformation conversion material, the constraint material and the sensing optical fibers, and the two types of sensing optical fibers are arranged in the optical cable, so that optical loss caused by other factors except leakage factors is reduced, and the monitoring reliability is improved. The invention has the advantages of simple sensing structure, mature OTDR technology, low cost, large monitoring distance, realization of low-cost and high-precision online monitoring of the leakage of the long-distance tunnel/pipeline, strong market competitiveness and beneficial effects of guaranteeing the safety of national infrastructure and protecting national resources.
Description
Technical field
The invention belongs to engineering monitorings, field of sensing technologies, and in particular to one kind can be used for long distance tunnel/pipe leakage
The optical cable of monitoring.
Background technique
Effect on environment small feature when because of construction, shield tunnel become subway, cross the river/traffic tunnels such as sea is main excessively
Form.But shield tunnel liner is spliced by prefabricated reinforced concrete segment by high-strength bolt, is existed between section of jurisdiction
Seam.General tunnel is buried underground water level or less, is also easy to produce water leakage.Leakage itself is not fearful, mainly easily leads to connection
Bolt corrosion makes Deterioration of Structural Performance.For the pipeline of water delivery, oil transportation, also easily on the transport route generate leakage, cause water,
The waste of oil, can also generation environment pollution.Therefore, seem very heavy to above-mentioned tunnel, pipeline configuration progress all fronts monitoring of leakage
It wants.But due to these two types of structures generally lay distance it is longer, can be usually reached tens kilometers or thousands of kilometers, at present it is existing
Technology can not also effectively to all fronts implement monitoring of leakage.
In sensory field of optic fibre, OTDR(Optical Time Domain Reflectometer) it is widely used in light
Among the maintenance on cable road, construction, carry out fiber lengths, the transmission attenuation of optical fiber, connector decaying andFault locationDeng measurement.
The basic principle of OTDR measurement be in analysis optical fiber the measurement of the method for rear orientation light or forward scattering light because the originals such as scattering, absorbing
Because of structural loss caused by the fiber transmission attenuation of generation and various faults of construction.When masterpiece by temperature or is answered in optical fiber certain point
The scattering properties of used time, the point will change, therefore can be outer to detect by display loss and the corresponding relationship of fiber lengths
Sector signal is distributed in the disturbance information on sensor fibre.Currently, the measurable maximum distance of OTDR reaches 400km, it is suitable for length
The monitoring of distance structure.Meanwhile the price of OTDR equipment also has competitiveness on the market, most products are lower than 100,000
Member.
Based on OTDR technique, the leakage of structure is converted into passing optical fiber the detection of light loss by the present invention, may be implemented low
Cost, efficient long distance tunnel/pipe leakage monitoring, while can temperature self-compensation.
Summary of the invention
It is an object of the invention to overcome problem above of the existing technology, provide a kind of for long distance tunnel/pipe
The sensing optic cable of road monitoring of leakage.
To achieve the above object, reach above-mentioned technical effect, the invention is realized by the following technical scheme:
It is a kind of that for long distance tunnel/pipe leakage monitoring sensing optic cable, the sensing optic cable includes monitoring of leakage optical cable,
Leakage sensor fibre and compensation sensor fibre are equipped in the monitoring of leakage optical cable, the leakage sensor fibre is set up directly on infiltration
In leakage-deformation transition material, and it is equipped with primary clearance between the leakage sensor fibre and leakage-deformation transition material, uses
To reduce initial light loss, the compensation sensor fibre is arranged in a stereoplasm tube, and the stereoplasm tube is wrapped in leakage-deformation and turns
In conversion materials, it is built-in it is described leakage sensor fibre and compensate sensor fibre leakage-deformation transition material outer top surface and
Constraint material is enclosed on two sides.
Further, the hard bore is greater than compensation sensor fibre outer diameter, in stereoplasm tube and compensation sense light
Gap is formed between fibre reduces initial light loss.
Further, the deformation that the deformation and stress that the leakage sensor fibre is generated by induction leakage generate generates light
Damage, the compensation sensor fibre, which only passes through to incude, generates light loss, the leakage sense light except leakage with the deformation that other factor generates
The fine light loss generated with compensation sensor fibre constitutes comparison induction, leaks to judge whether.
Further, the leakage sensor fibre absorbs leakage medium by leakage-deformation transition material, and volume becomes larger,
Leakage sensor fibre is squeezed, to make to leak sensor fibre generation light loss.
Further, the volume change after the leakage-deformation transition material absorption leakage medium is not less than 2 times.
Further, the leakage sensor fibre monitors the distribution and identification leakage of light loss using optical time domain reflection.
Preferably, the leakage-deformation transition material rigidity is less than stereoplasm tube and constraint material, and the leakage-
It deforms transition material and differs 20 times or more than stereoplasm tube and the elasticity modulus of constraint material, leak caused deformation to guarantee
It effectively is transferred to leakage sensor fibre, and is not passed to compensation sensor fibre.
The beneficial effects of the present invention are:
1, light loss distribution is generated using leakage sensor fibre deformation in the present invention to detect leakage, and passes through compensation sense light
Fibre incudes to compare, and solves long distance tunnel/pipeline and is difficult to the predicament that accurate, timely, comprehensive monitoring leaks at random, has
There are stronger applicability and the market competitiveness；
2, it is designed in the present invention by reasonable structure, converts leakage to the deformation of material, opened up monitoring of leakage
Type, for ensure engineering structure effectively, safe operation technical support is provided;
3, the configuration of the present invention is simple realizes long distance tunnel/pipe leakage low cost on-line monitoring, the market competitiveness
By force, beneficial effect is generated for guarantee national basis installation security and property safety.
The above description is only an overview of the technical scheme of the present invention, in order to better understand the technical means of the present invention,
And can be implemented in accordance with the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention and the accompanying drawings.
A specific embodiment of the invention is shown in detail by following embodiment and its attached drawing.
Detailed description of the invention
The drawings described herein are used to provide a further understanding of the present invention, constitutes part of this application, this hair
Bright illustrative embodiments and their description are used to explain the present invention, and are not constituted improper limitations of the present invention.In the accompanying drawings:
Fig. 1 is sensing optic cable structural schematic diagram of the invention；
Fig. 2 is the structural schematic diagram that sensing optic cable of the invention is laid in the duct；
Fig. 3 is the structural schematic diagram that sensing optic cable of the invention is laid in tunnel.
Figure label explanation: 1, sensor fibre, 2, compensation sensor fibre, 3, stereoplasm tube, 4, leakage-deformation conversion material are leaked
Material, 5, constraint material, 6, monitoring of leakage optical cable, 7, pipeline, 8, tunnel.
Specific embodiment
Below with reference to the accompanying drawings and in conjunction with the embodiments, design feature and technology implementation process of the invention be described in detail:
A kind of sensing optic cable monitored for long distance tunnel/pipe leakage, as shown in Figure 1, it is straight to leak sensor fibre 1
It connects and is arranged in leakage-deformation transition material 4, and there is certain primary clearance between the two, reduce the initial light loss of optical cable；
And compensate sensor fibre 2 and be then first arranged in stereoplasm tube 3, then be bundled together with leakage-deformation transition material 4, wherein hard
The internal diameter of pipe 3 is greater than the outer diameter of other compensation sensor fibres 2, reduces the initial light loss of optical cable；Then, in leakage-deformation conversion
The external of material 4 wraps up constraint material 5, wherein and the rigidity of constraint material 5 is much larger than leakage-deformation transition material 4 rigidity,
And guarantee leakage-deformation transition material 4 and monitoring of structures has sufficient contact area, in this way, leakage medium can be by leakage-change
Shape transition material 4 fully absorbs, and material volume becomes larger, and in the present embodiment, water suction/oil can be selected in leakage-deformation transition material 4
Swollen resin and rubber, constraint material 5 should have preferable environmental corrosion resisting and enough rigidity, intensity, optional stainless steel,
Fibrous composite or high molecular material；Since the rigidity of constraint material 5 and monitoring of structures is big, deformation can only inwardly develop, from
And leakage sensor fibre 1 is squeezed, it significantly increases it in leakage light loss, leakage position can directly be detected by OTDR technique
It sets；Deformed leakage-deformation transition material 4 can also squeeze stereoplasm tube 3, but since stereoplasm tube 3 has enough rigidity, prevent
It is squeezed and deformed and is transmitted on internal compensation sensor fibre 2, so that compensation 2 pairs of leakages of sensor fibre are insensitive；It is practicing
In, can also there be structure partial deformation, such as the deformation of big faulting of slab ends, the bending of aqueduct between shield duct piece, these deformations are big
The optical transmission performance that will affect sensor fibre to a certain extent leads to two type optical fibers (leakage sensor fibre 1 and compensation sensor fibre
2) local light loss is generated simultaneously, leakage can be improved by comparing two type optical fibers in the light loss of same position using structure of the invention
The confidence level of monitoring.
As shown in Fig. 2, be the application example of monitoring of leakage optical cable 6 of the invention in pipeline 7, it can be by monitoring of leakage optical cable
6 are mounted on the outside of pipeline 7.
As shown in figure 3, be the application example of monitoring of leakage optical cable 6 of the invention in tunnel 8, it can be by monitoring of leakage optical cable
6 are mounted on the inside in tunnel 8, during installation, except the direct contact surface of leakage-deformation transition material 4 monitoring of structures, leakage prison
The other positions for surveying optical cable 6 need to do seepage control measure, influence the evaluation of monitoring result to protect the medium other than monitoring objective not.
The foregoing is only a preferred embodiment of the present invention, is not intended to restrict the invention, for the skill of this field
For art personnel, the invention may be variously modified and varied.All within the spirits and principles of the present invention, made any to repair
Change, equivalent replacement, improvement etc., should all be included in the protection scope of the present invention.
Claims (6)
1. a kind of for long distance tunnel/pipe leakage monitoring sensing optic cable, which is characterized in that the sensing optic cable includes leakage
It monitors optical cable (6), leakage sensor fibre (1) and compensation sensor fibre (2), the infiltration is equipped in the monitoring of leakage optical cable (6)
Leakage sensor fibre (1) is set up directly in leakage-deformation transition material (4), and the leakage sensor fibre (1) and leakage-
It deforms and is equipped with primary clearance between transition material (4), to reduce initial light loss, the compensation sensor fibre (2) is arranged one
In stereoplasm tube (3), the stereoplasm tube (3) is wrapped in leakage-deformation transition material (4), in the built-in leakage sense light
Constraint material is enclosed in leakage-deformation transition material (4) outer top surface and two sides of fine (1) and compensation sensor fibre (2)
Expect (5), the leakage sensor fibre (1) incudes leakage and leakage simultaneously and is formed by light loss, the compensation sensing with other factor
The light loss that optical fiber (2) is only generated by induction except leakage with other factor, the leakage sensor fibre (1) and compensation sensor fibre
(2) light loss incuded constitutes comparison induction, leaks to judge whether.
2. according to claim 1 for long distance tunnel/pipe leakage monitoring sensing optic cable, which is characterized in that institute
It states stereoplasm tube (3) internal diameter and is greater than compensation sensor fibre (2) outer diameter, to the shape between stereoplasm tube (3) and compensation sensor fibre (2)
Initial light loss is reduced at gap.
3. according to claim 1 for long distance tunnel/pipe leakage monitoring sensing optic cable, which is characterized in that institute
It states leakage sensor fibre (1) and leakage medium is absorbed by leakage-deformation transition material (4), volume becomes larger, and squeezes leakage sense light
Fine (1), to make to leak sensor fibre (1) generation light loss.
4. according to claim 3 for long distance tunnel/pipe leakage monitoring sensing optic cable, which is characterized in that institute
Volume change after stating leakage-deformation transition material (4) absorption leakage medium is not less than 2 times.
5. according to claim 1 or 3 for long distance tunnel/pipe leakage monitoring sensing optic cable, which is characterized in that
The leakage sensor fibre (1) and compensation sensor fibre (2) are all made of optical time domain reflection to monitor distribution of the light loss along optical fiber.
6. according to claim 1 for long distance tunnel/pipe leakage monitoring sensing optic cable, which is characterized in that institute
Leakage-deformation transition material (4) rigidity is stated less than stereoplasm tube (3) and constraint material (5), and the leakage-deformation is converted
Material (4) differs 20 times or more than stereoplasm tube (3) and the elasticity modulus of constraint material (5), leaks caused change to guarantee
Shape is effectively transferred to leakage sensor fibre (1), and is not passed to compensation sensor fibre (2).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510472980.XA CN105022131B (en) | 2015-08-05 | 2015-08-05 | Sensing optical cable for monitoring leakage of long-distance tunnel/pipeline |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510472980.XA CN105022131B (en) | 2015-08-05 | 2015-08-05 | Sensing optical cable for monitoring leakage of long-distance tunnel/pipeline |
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| Publication Number | Publication Date |
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| CN105022131A CN105022131A (en) | 2015-11-04 |
| CN105022131B true CN105022131B (en) | 2019-02-01 |
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| CN201510472980.XA Expired - Fee Related CN105022131B (en) | 2015-08-05 | 2015-08-05 | Sensing optical cable for monitoring leakage of long-distance tunnel/pipeline |
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Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105546270A (en) * | 2016-03-07 | 2016-05-04 | 深圳市巍特工程技术有限公司 | Lining structure, pipe and pipe repairing method |
| CN108562310A (en) * | 2018-01-29 | 2018-09-21 | 衡东光通讯技术（深圳）有限公司 | A kind of water leak detector |
| CN109764246B (en) * | 2019-03-14 | 2020-09-29 | 广东聚源管业实业有限公司 | Pipeline interface leakage monitoring method |
| CN110108308A (en) * | 2019-05-27 | 2019-08-09 | 华南理工大学 | A kind of power cable water inlet on-Line Monitor Device |
| CN110132325A (en) * | 2019-05-27 | 2019-08-16 | 华南理工大学 | A kind of power cable water inlet sensing device based on stress enhancing structure |
| CN110410685B (en) * | 2019-07-11 | 2020-11-24 | 西北工业大学 | Underground pipe network leakage positioning system and method based on time domain reflection technology |
| CN112987210A (en) * | 2021-02-08 | 2021-06-18 | 北京百世通管道科技有限公司 | Sensing optical fiber unit structure for pipeline risk monitoring and early warning and construction method |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07225173A (en) * | 1994-02-10 | 1995-08-22 | Sumitomo Electric Ind Ltd | Housing structure of liquid-leak detection sensor using optical fiber |
| CN1135807A (en) * | 1993-09-23 | 1996-11-13 | 加利福尼亚光波实验室公司 | Method and apparatus for detecting hydrocarbon fuels |
| CN1587945A (en) * | 2004-09-13 | 2005-03-02 | 西安交通大学 | Sensitive optical cable for long distance oil-gas pipeline safety detection |
| CN201043927Y (en) * | 2007-05-18 | 2008-04-02 | 中国科学院上海光学精密机械研究所 | Full-distributed optical fiber oil leakage sensor system |
| CN204514563U (en) * | 2015-03-19 | 2015-07-29 | 成都誉华科技有限公司 | A kind of extrusion pressing type fibre-optical sensing device responsive to oil |
-
2015
- 2015-08-05 CN CN201510472980.XA patent/CN105022131B/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1135807A (en) * | 1993-09-23 | 1996-11-13 | 加利福尼亚光波实验室公司 | Method and apparatus for detecting hydrocarbon fuels |
| JPH07225173A (en) * | 1994-02-10 | 1995-08-22 | Sumitomo Electric Ind Ltd | Housing structure of liquid-leak detection sensor using optical fiber |
| CN1587945A (en) * | 2004-09-13 | 2005-03-02 | 西安交通大学 | Sensitive optical cable for long distance oil-gas pipeline safety detection |
| CN201043927Y (en) * | 2007-05-18 | 2008-04-02 | 中国科学院上海光学精密机械研究所 | Full-distributed optical fiber oil leakage sensor system |
| CN204514563U (en) * | 2015-03-19 | 2015-07-29 | 成都誉华科技有限公司 | A kind of extrusion pressing type fibre-optical sensing device responsive to oil |
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| CN105022131A (en) | 2015-11-04 |
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