CN105300944B - A kind of concrete chloride ion corrosion fibre optical sensor and its detection method based on fluorescent quenching - Google Patents
A kind of concrete chloride ion corrosion fibre optical sensor and its detection method based on fluorescent quenching Download PDFInfo
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- CN105300944B CN105300944B CN201510765232.0A CN201510765232A CN105300944B CN 105300944 B CN105300944 B CN 105300944B CN 201510765232 A CN201510765232 A CN 201510765232A CN 105300944 B CN105300944 B CN 105300944B
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- transmission fibers
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- chloride ion
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Abstract
The present invention provide it is a kind of based on fluorescent quenching concrete chloride ion corrosion fibre optical sensor and its detection method, the sensor include protective case, Transmission Fibers and photofilm sub-assembly；Protective case one end is encapsulated with bolt and is fixed, and the other end is closed with microporous ceramic structure, and chloride conductance colloidal substance is perfused in protective case；Transmission Fibers are the reflection-type optical fiber with two-way transmission capabilities, Transmission Fibers are one close to microporous ceramic structure one end, a piece Transmission Fibers are connected with photofilm sub-assembly, Transmission Fibers encapsulate one end close to bolt and are divided into two, two Transmission Fibers are pierced by from bolt encapsulating face, wherein one is excitation injection light source, and another is fluorescent collecting transmission light source；Photofilm sub-assembly includes PVC outline borders and its interior quartz plate and light-sensitive surface, and PVC outline borders one end and Transmission Fibers gluing, the other end are fixed through hold-down bolt.The sensing is embedded into inside concrete, you can realize the on-line checking of trace chlorine inside armored concrete.
Description
Technical field
The present invention relates to the envelopes of the reinforcement corrosion fiber optic sensor under Chloride Attack environment in traffic, field of civil engineering
Dress and protection field, are specifically directed to extra large work harbour reinforced concrete structure erosion problem, and research and development one kind is quenched based on fluorescence
The concrete chloride ion corrosion fibre optical sensor to go out, to realize trace chlorine on-line checking inside armored concrete.
Background technology
Chlorion invades and concrete carbonization causes steel bar corrosion to be the main original for causing concrete structure durability to decline
Cause seriously threatens the service safety of concrete structure.For the reinforced concrete structure of sea port dock, chlorion invasion
Caused concrete structure Problem of Failure is particularly acute.Usual rebar surface forms passivating film under concrete high alkalinity environment,
But chlorion is adsorbed on rebar surface and can destroy passivating film, while rebar surface pH value is reduced, passivating film failure is eventually led to,
Accelerate reinforcement corrosion.Therefore, grasp inside concrete chlorine ion concentration distribution situation, could to its durability and remaining life into
Row effectively assessment and prediction takes timely measure serious chlorion intrusion region, improves the overall security of structure.
Chloride test method is to obtain some coagulations from inside by the way of probing inside traditional concrete structure
The method of chemical analysis is recycled to determine its chloride ion content after soil.It is accurate that this kind of method measures, but time-consuming and laborious, especially
It can not achieve real-time monitoring.Another measurement method is to lay reference electrode in inside concrete using electrochemical method, works as chlorine
Reinforcement corrosion, current potential is caused to change after ion intrusion inside concrete.It can be calculated based on Nernst equation potential change
Go out chlorine ion concentration (application number：201320007940.4).In early days, VTI companies in the U.S. develop based on linear polarization technique
Reinforcement corrosion rate monitors sensor, and domestic Harbin Institute of Technology also has developed based on MnO2Solid state reference electrode, electrode
Stability height, long lifespan (application number：200910073383.4).Patent 201320136419.0 is combined using a variety of reference electrodes
The chlorine ion concentration and pH value of concrete are measured respectively.
Line fiber optical differential protection technology is that the 1970s is rapid with optical-fibre communications and the development of photoelectron technology
Grow up using light wave as transmission medium, the New Sensing Technology of extraneous measured signal is perceived and transmitted by optical fiber, is had
Small and light, it is anticorrosive, not charged, not by electromagnetic interference, it is nonflammable it is explosive, be suitble to small space, sensing one etc. the advantages that.
It is a kind of completely new path to be monitored to reinforcement corrosion situation using fibre optical sensor, and patent 201310292078.0 discloses
A kind of steel reinforcement corrosion sensor based on Fiber Bragg Grating technology, reinforcement corrosion lead to its own volume expansion and then promote to wind it
Outer fiber grating spacing variation.University Of Tianjin proposes the seawater chlorine ion concentration measuring device (Shen based on double optical fiber grating
Please number：201310756330.9 with 201310274636.0).Reinforcement corrosion fiber optic sensor has been invented by Nanjing Aero-Space University
Packaging method (application number：200910029971.8).Optical fiber chlorion sensor also has application in medical domain, as Fudan University is big
Learn the optical fiber surface fluorescence blood chloride sensor (application number proposed：201510031062.X), contained by optical fiber connector coating
It is made of the polymer of photographic composition, fluorescence sense high sensitivity and ion selectivity is good, temperature pH value is adaptable.Based on glimmering
The concrete chloride ion corrosion fibre optical sensor of optical quenching has not been reported and related patents.
Invention content
The technical assignment of the present invention be in view of the deficiencies of the prior art, provide a kind of concrete chlorine based on fluorescent quenching from
Son corrosion fibre optical sensor, to realize trace chlorine on-line checking inside armored concrete.
The technical solution adopted by the present invention to solve the technical problems is：
1, the present invention provides a kind of concrete chloride ion based on fluorescent quenching and corrodes fibre optical sensor, including protective case and
The Transmission Fibers and photofilm sub-assembly being inside located in protective case；
The protective case uses high-strength structure for support, and one end is fixed using bolt encapsulation, and the other end uses micropore
Ceramic structure is closed, and surrounds confined space between protective case, bolt encapsulating face and microporous ceramic structure sealing surface, in confined space
Chloride conductance colloidal substance is perfused；
The Transmission Fibers are the reflection-type optical fiber with two-way transmission capabilities, and Transmission Fibers are close to microporous ceramic structure one
End is one, which is connected with photofilm sub-assembly, and Transmission Fibers encapsulate one end close to bolt and are divided into two,
And be pierced by from bolt encapsulating face after two Transmission Fibers tensions, wherein one is excitation injection light source, another is adopted for fluorescence
Collect transmission light source；
The photofilm sub-assembly includes that PVC outline borders and its interior quartz plate and light-sensitive surface, quartz plate and light-sensitive surface lean on
Nearly microporous ceramic structure one end is mounted on inside PVC outline borders from the distant to the near, the Transmission Fibers of PVC outline borders and close quartz plate one end
Gluing connects, and PVC outline borders are fixed close to light-sensitive surface one end using hold-down bolt.
Further, the quartz plate locating groove for placing quartz plate is equipped in the PVC outline borders.
Further, Nafion membrane is added between the chloride conductance colloidal substance and micropore ceramics.
Further, the locating plate for constant transmissions optical fiber is equipped in the protective case.
The protective case uses mild steel steel pipe or fiber glass epoxy to be supported for high-strength structure.
The chloride conductance colloidal substance is agar.
2, the present invention also provides a kind of, and the concrete chloride ion based on fluorescent quenching corrodes the detection method of fibre optical sensor,
It is characterized in that, by it is above-mentioned it is a kind of based on fluorescent quenching concrete chloride ion corrosion fibre optical sensor be embedded into concrete
Portion, Transmission Fibers one end connection excitation injection light source, the other end connect fluorescent collecting device.
A kind of concrete chloride ion based on fluorescent quenching of the present invention corrodes fibre optical sensor and its detection method and shows
There is technology to compare, generated advantageous effect is：
The present invention is directed to extra large work harbour reinforced concrete structure erosion problem, using researching and developing small-sized chlorion based on optical fiber
Sensor transmits injection exciting light by Transmission Fibers and receives fluorescent emission, reacts knot with exciting light generation using light-sensitive surface
The chlorine ion concentration closed near film is different, generates varying strength fluorescence, and then realize the detection to chlorion, which has
Small, the advantages that light weight and cost is low, precision is high, detection method is easy to operate, convenient and practical, has certain exploitation
Foreground.
Description of the drawings
Attached drawing 1 is that the present invention is based on the structural schematic diagrams that the concrete chloride ion of fluorescent quenching corrodes fibre optical sensor；
Attached drawing 2 is the encapsulating structure schematic diagram of Transmission Fibers of the present invention and light-sensitive surface；
Attached drawing 3 is that the present invention is based on the fluorescence intensity test knots that the concrete chloride ion of fluorescent quenching corrodes fibre optical sensor
Fruit is schemed.
In figure, 1, Transmission Fibers, 2, bolt, 3, locating plate, 4, agar, 5, micropore ceramics, 6, photofilm sub-assembly, 7,
PVC outline borders, 8, light-sensitive surface, 9, gluing, 10, quartz plate locating groove, 11, quartz plate, 12, hold-down bolt, 13, protective case, it is attached
Fig. 3 curves a → f represents fluorescence intensity test chart after addition various concentration NaCl solution 0.1mL.(wherein, a → f NaCl are successively
For 0mol/L, 005mol/L, 0.01mol/L, 0.02mol/L, 0.03mol/L 0.04mol/L, 0.05mol/L)
Specific implementation mode
1-3 corrodes fibre optical sensor to a kind of concrete chloride ion based on fluorescent quenching of the present invention below in conjunction with the accompanying drawings
And its detection method is described in detail below.
As shown in Fig. 1, a kind of concrete chloride ion based on fluorescent quenching of the invention corrodes fibre optical sensor, including
Protective case 13 and the interior Transmission Fibers 1 being located in protective case 13 and photofilm sub-assembly 6.Protective case 13 is used to support sensor
Internal structure, protection sensor will not be destroyed in concreting and solidification, and Transmission Fibers 1 are primarily used to transmission note
Enter exciting light and receive fluorescent emission, light-sensitive surface 8 generates the chlorine ion concentration near reaction bonded film not according to itself and exciting light
Together, varying strength fluorescence is generated.
The protective case 13 of the present invention is using mild steel steel pipe (or the high-strength structures such as fiber glass epoxy) as support, one
End is fixed using the encapsulation of bolt 2, and the other end is closed using 5 structure of micropore ceramics, can both protect internal structure, while being convenient for chlorine
The conduction of ion.Confined space is surrounded between 5 structure sealing surface of protective case 13,2 encapsulating face of bolt and micropore ceramics, light will be transmitted
Fibre 1 and photofilm sub-assembly 6 are placed in inside confined space, and inside is prevented using locating plate 3 (or other location structures) design
Transmission Fibers 1 move, other spaces are using perfusion agar 4 (other colloidal substances for being conducive to chloride conductance can also be used), fine jade
Increase Nafion membrane between fat 4 and porous ceramics to keep 4 long-time stability of agar.
The Transmission Fibers 1 of the present invention are the reflection-type optical fiber with two-way transmission capabilities, and Transmission Fibers 1 are close to micropore ceramics
5 structure one end are one, which is connected with photofilm sub-assembly 6, and Transmission Fibers 1 are close to the encapsulation of bolt 2 one
End is divided into two, and is pierced by from 2 encapsulating face of bolt after two tensions of Transmission Fibers 1, wherein one is excitation injection light source, separately
One is fluorescent collecting transmission light source.
As shown in Fig. 2, photofilm sub-assembly 6 of the invention includes PVC outline borders 7 and its interior quartz plate 11 and photosensitive
Film 8, quartz plate 11 and light-sensitive surface 8 are mounted on inside PVC outline borders 7 from the distant to the near close to 5 structure one end of micropore ceramics, the PVC
The quartz plate locating groove 11 for placing quartz plate 11, the biography of PVC outline borders 7 and close 11 one end of quartz plate are equipped in outline border 7
Fine 1 gluing 9 connection is lost, PVC outline borders 7 are fixed close to 8 one end of light-sensitive surface using hold-down bolt 12.
Light-sensitive surface 8 of the present invention prepares silica bearing substrate using the method for collosol and gel (Sol-gel), and two
Silica supported matrix is in molar ratio 1: 6: 2: 0.001 using ethyl orthosilicate, absolute ethyl alcohol, deionized water, ammonium hydroxide,
It is mixed under stirring, after persistently stirring 12 hours, static ageing 72 hours.In the silica Sol-gel colloidal sols prepared
Middle bis- (N- methylacridines) nitrate Lucigenin that 0-1mL 0.001mol/L are added dropwise are to obtain photosensitive stoste.With dustless stone
English piece 11 is base material, and size 10*10*0.5mm prepares light-sensitive surface 8, lifting speed by the way of lifting on 11 surface of quartz plate
1mm/min is spent, obtains and spontaneously dries 48 hours after there is 8 quartz plate 11 of light-sensitive surface, 60 DEG C of dryings 4 hours, 8 quartz plate of light-sensitive surface
11 are packaged with Transmission Fibers 1 using Fig. 2 structures.Usually when 350nm exciting lights are irradiated to light-sensitive surface 8, in light-sensitive surface 8
Lucigenin is activated, and when it falls back to ground state from excitation state, can emit fluorescence.Light-sensitive surface 8 is entered when there is chlorion
When, excitation state is fallen after rise to ground state process electrons mutually collides with chlorion, and fluorescence intensity is caused to reduce, and then realizes chlorion
Detection.
As shown in Fig. 3, coagulation is used as using the NaCl solution (0.005mol/L-0.05mol/L) of 0.1mL various concentrations
Native simulated solution, chloride ion corrosion fibre optical sensor is put into simulated solution impregnate 2 hours so that internal structure external structure in chlorion
Concentration reaches stable.It is glimmering that chloride ion corrosion fibre optical sensor is connected into a FluoroMax-4 Spectrofluorometer
Photothermal spectroscopic analyzer, is capable of providing 350nm wavelength excitation light source and the fluorescence to receiving (400-700nm wavelength) carries out intensity point
Analysis, test results are shown in figure 3.The result shows that the sensor can realize low-level chlorinated ion in detection solution.By above-mentioned chlorine from
Son corrosion fibre optical sensor is embedded into inside concrete, 1 one end of Transmission Fibers connection excitation injection light source, and the other end connects fluorescence
The on-line checking of trace chlorine inside armored concrete can be realized in harvester.
Claims (6)
1. a kind of concrete chloride ion based on fluorescent quenching corrodes fibre optical sensor, which is characterized in that including protective case and interior
The Transmission Fibers and photofilm sub-assembly being located in protective case；
The protective case uses mild steel steel pipe or fiber glass epoxy to be supported for high-strength structure, and one end is solid using bolt encapsulation
Fixed, the other end is closed using microporous ceramic structure, is surrounded between protective case, bolt encapsulating face and microporous ceramic structure sealing surface close
Space is closed, chloride conductance colloidal substance is perfused in confined space；
The Transmission Fibers are the reflection-type optical fiber with two-way transmission capabilities, and Transmission Fibers are close to microporous ceramic structure one end
One, which is connected with photofilm sub-assembly, and Transmission Fibers encapsulate one end close to bolt and are divided into two, and should
Two Transmission Fibers are pierced by after tensing from bolt encapsulating face, wherein one is excitation injection light source, another passes for fluorescent collecting
Source is lost, optical source wavelength 350nm, the reception wavelength of fluorescence 400-700nm of the fluorescent collecting transmission light source are injected in the excitation；
The photofilm sub-assembly includes PVC outline borders and its interior quartz plate and light-sensitive surface, light-sensitive surface include Lucigenin,
Quartz plate and light-sensitive surface are mounted on inside PVC outline borders from the distant to the near close to microporous ceramic structure one end, PVC outline borders and close quartz
The Transmission Fibers gluing of piece one end connects, and PVC outline borders are fixed close to light-sensitive surface one end using hold-down bolt.
2. a kind of concrete chloride ion based on fluorescent quenching according to claim 1 corrodes fibre optical sensor, feature
It is, the quartz plate locating groove for placing quartz plate is equipped in the PVC outline borders.
3. a kind of concrete chloride ion based on fluorescent quenching according to claim 1 or 2 corrodes fibre optical sensor, special
Sign is, Nafion membrane is added between the chloride conductance colloidal substance and micropore ceramics.
4. a kind of concrete chloride ion based on fluorescent quenching according to claim 1 or 2 corrodes fibre optical sensor, special
Sign is, the locating plate for constant transmissions optical fiber is equipped in the protective case.
5. a kind of concrete chloride ion based on fluorescent quenching according to claim 1 or 2 corrodes fibre optical sensor, special
Sign is that the chloride conductance colloidal substance is agar.
6. a kind of detection method of the concrete chloride ion corrosion fibre optical sensor based on fluorescent quenching, which is characterized in that will weigh
Profit requires a kind of 1 or 2 concrete chloride ion corrosion fibre optical sensor based on fluorescent quenching to be embedded into inside concrete, transmits
Optical fiber one end connection excitation injection light source, the other end connect fluorescent collecting device.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201510765232.0A CN105300944B (en) | 2015-11-11 | 2015-11-11 | A kind of concrete chloride ion corrosion fibre optical sensor and its detection method based on fluorescent quenching |
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| CN201510765232.0A CN105300944B (en) | 2015-11-11 | 2015-11-11 | A kind of concrete chloride ion corrosion fibre optical sensor and its detection method based on fluorescent quenching |
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| CN106885767A (en) * | 2017-02-22 | 2017-06-23 | 内蒙古科技大学 | A kind of method for detecting the resistance to sulfidation corrosion of concrete |
| CN111019168B (en) * | 2019-12-24 | 2022-02-25 | 福建第一公路工程集团有限公司 | Preparation method of sensitive membrane of optical fiber sensor for detecting chloride ions in concrete pore solution |
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Patent Citations (7)
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| JPH04194649A (en) * | 1990-11-27 | 1992-07-14 | Hitachi Metals Ltd | Method for testing macro-corrosion of large material to be inspected |
| CN101509876A (en) * | 2009-03-30 | 2009-08-19 | 南京航空航天大学 | Method for packaging reinforcement corrosion fiber optic sensor |
| CN101566580A (en) * | 2009-05-13 | 2009-10-28 | 南京航空航天大学 | Method for monitoring steel bar corrosion state in concrete by stages and sensor |
| US8833146B2 (en) * | 2010-04-26 | 2014-09-16 | Southwest Research Institute | Corrosion sensor |
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