CN101923057A

CN101923057A - BOTDR (Brillouin Optical Time-Domain Reflectometer) fiber optical corrosive sensor

Info

Publication number: CN101923057A
Application number: CN 201010159640
Authority: CN
Inventors: 赵雪峰; 宫鹏; 欧进萍
Original assignee: Dalian University of Technology
Current assignee: Dalian University of Technology
Priority date: 2010-04-29
Filing date: 2010-04-29
Publication date: 2010-12-22
Anticipated expiration: 2030-04-29
Also published as: CN101923057B

Abstract

The invention discloses a BOTDR (Brillouin Optical Time-Domain Reflectometer) fiber optical corrosive sensor, realizing the corrosion monitoring by adopting a cheap single-mode communication optical fiber as a sensing element. The sensor is used for measuring the corrosion destructive degree of a structure and comprises a rebar, a permeable layer, an organic glass blade, a lubricating layer, a bare fiber, an armored cable, and a permeable packing box. A manufacture method of the sensor comprising the steps of: covering the permeable layer on the rebar, uniformly clamping the rebar by using the organic glass blade, winding the bare fiber on the organic glass blade covered with the lubricating layer, connecting the bare fiber and the armored cable, and finally packing with the permeable packing box and leading out the armored cable through an leading-out end. The sensor is applicable to the structural health monitoring of the civil engineering, such as a concrete dam, and the interiors of some structures suffered from corrosion frequently, has simple process, convenient arrangement and high precision, and is suitable to industrialization production.

Description

BOTDR fiber optical corrosive sensor

Technical field

The present invention is a kind of sensor that uses optical fiber to monitor reinforced concrete structure reinforcement corrosion degree, be exactly by strain sensing technology specifically, utilize and twine the measurement of cheap single mode communication optical fiber realization the strain of reinforcement corrosion after expansion based on optical fiber BOTDR (Brillouin light domain reflectometer).By producing volumetric expansion strain phenomenon after the monitoring reinforcement corrosion, realize Quantitative Monitoring to the reinforcement corrosion degree.

Background technology

Optical fiber is the desirable sensing element that is used for long term monitoring, and it has advantages such as stable performance, multiparameter and distribution measuring, thereby extremely payes attention in the monitoring structural health conditions sensing technology in recent years.Though the time of Fibre Optical Sensor research is not long, makes progress very fast.

(Brillouin Optical Time-Domain Relectometer, measuring technique BOTDR) is a sophisticated technology that is used for optical communication and monitoring structural health conditions that just occurs for over ten years in the world to the Brillouin light domain reflectometer.Brillouin scattering is that incident light wave and sound wave interact and a kind of inelastic scattering of generation, and the stokes light that produces in scattering process has a frequency displacement with respect to pump light, becomes Brillouin shift.The Brillouin shift amount that scattering produces is directly proportional with the velocity of sound in the optical fiber.And the refractive index in the optical fiber and the velocity of sound are all relevant with the temperature of optical fiber and suffered factors such as stress, based on this principle, can realize monitoring to strain and temperature by the measurement to the Brillouin shift amount.Compare with the traditional monitoring technology, the BOTDR technology has advantages such as distributed monitoring, long distance, corrosion-resistant and anti-electromagnetic interference (EMI), can directly utilize common communication optical fiber directly to monitor demodulation, realize that kilometer level range inner fiber is subjected to the continuous distribution formula measurement of strain and temperature as sensor.The most significant advantage of BOTDR technology is exactly stress, the temperature information that can measure exactly on the optical fiber any point along the line.If be laid to the netted monitoring net that just can possess certain scale with optical fiber is crisscross, realize comprehensive monitoring to monitoring target, overcome the drawback of conventional port monitoring omission, improve the success ratio of monitoring.

Optical fiber is cheap in the reality, is easy to form large-scale production, so it has good practicality, compares with fiber grating to have more generalization.

Summary of the invention

The technical problem to be solved in the present invention provides the sensor that a kind of monitoring of structures is subjected to extent of corrosion, this corrosion sensor has good precision, can satisfy requirement of engineering, owing to adopt the single mode communication optical fiber as sensing element, cost is cheaper than existing fiber grating corrosion sensor.

Technical scheme of the present invention is as follows:

This corrosion sensor comprises: deformed bar, pervious bed, organic glass blade, lubricating layer, bare fibre, armouring optical cable, permeable enclosure.At first add on the deformed bar and cover pervious bed, the organic glass blade) clamp deformed bar and pervious bed; Add lubricating layer on the organic glass blade, bare fibre evenly is wrapped on the lubricating layer closely; Connect bare fibre and armouring optical cable, bare fibre is wrapped on the organic glass blade of lubricating layer covering, with the permeable enclosure encapsulation in hole with holes, at exit the armouring optical cable is drawn then.

The invention has the beneficial effects as follows that technology is simple, be suitable for industrialization production, with low cost; Can use the monitoring of a signal processing and analysis device realization to a plurality of corrosion sensors; Sensor is laid convenient, fast, easy operating, measuring accuracy height.

Description of drawings

Fig. 1 is the Fibre Optical Sensor skeleton view.

Fig. 2 is the Fibre Optical Sensor transverse cross-sectional view.

Fig. 3 is the Fibre Optical Sensor longitudinal sectional drawing.

Among the figure: 1 deformed bar; 2 pervious beds; 3 organic glass blades; 4 lubricating layers; 5 bare fibres; 6 armouring optical cables; 7 permeable enclosure.

Embodiment

Be described in detail specific embodiments of the invention below in conjunction with technical scheme and accompanying drawing.

The fiber optical corrosive sensor construction constitutes as Fig. 1, Fig. 2 and shown in Figure 3, and this corrosion sensor comprises: 1 deformed bar; 2 pervious beds; 3 organic glass blades; 4 lubricating layers; 5 bare fibres; 6 armouring optical cables; 7 permeable enclosure.At first on deformed bar, add and cover pervious bed, afterwards the organic glass blade is evenly clamped deformed bar, again bare fibre is wrapped on the organic glass blade of lubricating layer covering, connect bare fibre and armouring optical cable then, at last with permeable enclosure encapsulation, and by exit the armouring optical cable is drawn.

Claims

1. a BOTDR fiber optical corrosive sensor comprises deformed bar (1), pervious bed (2), organic glass blade (3), lubricating layer (4), bare fibre (5), armouring optical cable (6) and permeable enclosure (7); It is characterized in that:

Add on the deformed bar (1) and cover pervious bed (2), organic glass blade (3) is clamped deformed bar (1) and pervious bed (2); Add lubricating layer (4) on the organic glass blade (3), bare fibre evenly is wrapped on the lubricating layer closely; Connect bare fibre (5) and armouring optical cable (6), bare fibre (5) is wrapped on the organic glass blade of lubricating layer covering, uses permeable enclosure (7) encapsulation in hole with holes then, at exit armouring optical cable (5) is drawn.