CN201569416U

CN201569416U - Intelligent type cable fiber grating strain transducer

Info

Publication number: CN201569416U
Application number: CN2009201881449U
Authority: CN
Inventors: 姜德生; 李盛; 赵霞; 刘礼华; 刘胜春; 周明宝; 张恩隆
Original assignee: Wuhan University of Technology WUT
Current assignee: Wuhan University of Technology WUT; Fasten Group Co Ltd
Priority date: 2009-09-30
Filing date: 2009-09-30
Publication date: 2010-09-01
Anticipated expiration: 2019-09-30

Abstract

The utility model relates to an intelligent type cable fiber grating strain transducer which is suitable for the cable bearing structures of cable-stayed bridges, suspension bridges, arch bridges and the like. The intelligent type cable fiber grating strain transducer comprises a fiber grating (1), first steel pipes (3), second steel pipes (2), a protective steel pipe (6) and a supporting seat (4), wherein the diameter of the second steel pipes (2) is smaller than the diameter of the first steel pipes (3) and is smaller than the diameter of the protective steel pipe (6), the middles of the second steel pipes (2) are axially provided with grooves, the middles of the first steel pipes (3) penetrate through a perforation at an upper area of the supporting seat (4) and are connected on the supporting seat (4), both ends of the protective steel pipe (6) are respectively sleeved at one end of the two first steel pipes (3), the other ends of the first steel pipes (3) are sleeved at one end of the second steel pipes (2), the fiber grating (1) penetrates through the second steel pipes (2), the first steel pipes (3) and the protective steel pipe (6), a grid area of the grating is arranged at the central position of the protective steel pipe (6), and tail fibers at both ends of the fiber grating (1) are led out from the other ends of the two second steel pipes (2). The utility model can enhance the survival rate of a fiber grating transducer and fibers in the manufacture and application processes of cables and ensures the reliability of the embedding process of the fiber grating transducer.

Description

Intelligent cable fiber grating strain sensor

(1) technical field

The utility model relates to a kind of built-in cable fiber grating strain sensor applicable to cable load-carrying members such as cable-stayed bridge, suspension bridge, arch bridges.

(2) background technology

The cable system is the core supporting member of bridge structures such as modern large span stayed-cable bridge, suspension bridge.Dynamic load on the deadweight of long-span bridge girder construction and the bridge, the overwhelming majority are to be delivered on the king-post by funicular system, and the duty of cable is directly to reflect one of important symbol whether bridge is in a safe condition.But owing to reasons such as structure design, environmental corrosion, fatigue accumulations, damage and deterioration in various degree appears in cable in-service unavoidably, estimates the stress of bridge cable system, and the use and the security that can be bridge cable provide decision-making foundation.What present Suo Li to cable generally adopted is the mode of external monitoring, if sensor organically can be integrated into cable inside, make its cable rise to intelligent cable with automatic perception from a simple load, to more help structural safety and the operation state that people grasp cable self and full-bridge, the tendency of discovery accident in time, prevent that sudden accident from taking place.

Fiber grating is a kind of sensitive element of function admirable, can respond to extraneous small strain variation by moving of bragg reflection wavelength and realize the structural stress on-line monitoring.It has the rugged surroundings of not being afraid of, be not subjected to ambient noise interference, anti-electromagnetic interference (EMI), collection sensing be transmitted in characteristics such as one, simple structure, easy to use, measuring accuracy height.

But the fiber grating without special processing is very fragile, directly is arranged in the cable, and is destroyed easily.Fiber grating is combined with cable, how to relate to fiber grating, improve fiber-optic grating sensor and the survival rate of optical fiber in cable manufacturing and application process with which kind of packing forms; How the fiber-optic grating sensor that encapsulates is built in cable inside, guarantees that fiber-optic grating sensor heeling-in technology is reliable.

(3) summary of the invention

The purpose of this utility model is to overcome above-mentioned deficiency, provides a kind of and can improve survival rate in cable manufacturing and application process of fiber-optic grating sensor and optical fiber, guarantees the reliable intelligent cable fiber grating strain sensor of fiber-optic grating sensor heeling-in technology.

The purpose of this utility model is achieved in that a kind of intelligent cable fiber grating strain sensor; comprise fiber grating; first steel pipe; second steel pipe; protection steel pipe and bearing; described protection steel pipe has one; first steel pipe; the bearing and second steel pipe all have two; two first steel pipes; two bearings and two second steel pipes are symmetrically arranged in the right and left of described protection steel pipe; wherein the diameter of diameter first steel pipe of second steel pipe is less than the diameter of protection steel pipe; axially grooved in the middle of described second steel pipe; the perforation of bearing upper area; passing described bearing upper area perforation in the middle of first steel pipe is connected on the bearing; the two ends of protection steel pipe are set in an end of described two first steel pipes; the other end of first steel pipe is sleeved on an end of described second steel pipe; fiber grating passes second steel pipe; first steel pipe and protection steel pipe; the grating grid region is in protection steel pipe center; the fiber grating two ends are fixed in the groove of described two second steel pipes with glue; the second steel pipe fluting place overcoat thermal shrinkable sleeve, described fiber grating two ends tail optical fiber is drawn by the other end of described two second steel pipes.

The beneficial effects of the utility model are:

The utility model is connected with the effective of cable inner wire by this sensor, can improve fiber-optic grating sensor and the optical fiber survival rate in cable manufacturing and application process, guarantee that fiber-optic grating sensor heeling-in technology is reliable, the production process that makes fiber grating withstand cable is not destroyed.Guarantee that sensor can be operated under the big stress state steadily in the long term.Make the wavelength variations of fiber grating can reflect the steel wire stressing conditions of cable inside faithfully, and then monitor the whole stressing conditions of cable effectively.

(4) description of drawings

Fig. 1 is the utility model intelligent cable fiber grating strain sensor structural representation.

Fig. 2 is the second steel pipe synoptic diagram of the present utility model.

Fig. 3 is a bearing part drawing of the present utility model.

Fig. 4 is the A-A cut-away view of Fig. 3.

Fig. 5 is the steel wire connection diagram of the utility model intelligent cable fiber grating strain sensor and cable.

Reference numeral among the figure:

Fiber grating 1, second steel pipe 2, first steel pipe 3, bearing 4, thermal shrinkable sleeve 5, protection steel pipe 6, steel wire 7.

(5) embodiment

Referring to Fig. 1, Fig. 1 is the utility model intelligent cable fiber grating strain sensor structural representation.As seen from Figure 1; the intelligent cable fiber grating strain sensor that the utility model relates to; comprise fiber grating 1; second steel pipe 2; first steel pipe 3; the bearing 4 that the protection steel pipe 6 that diameter is slightly thick and being used for is connected with steel wire with cable; described protection steel pipe 6 has one; first steel pipe 3; the bearing 4 and second steel pipe 2 all have two; two first steel pipes 3; two bearings 4 and two second steel pipes 2 are symmetrically arranged in the right and left of described protection steel pipe 6; wherein the diameter of second steel pipe 2 is less than the diameter of first steel pipe 3 diameter less than protection steel pipe 6; axially grooved in the middle of described second steel pipe 2, as Fig. 2.Bearing 4 upper areas are bored a hole, as Fig. 3 and Fig. 4, passing described bearing 4 upper areas perforation in the middle of first steel pipe 3 with certain gauge length is connected on the bearing 4, described first steel pipe, 3 intermediate radial are cut and are divided into two, the purpose of cutting is that power is directly delivered on the fiber grating, promptly directly draw fiber grating, avoided first steel pipe 3 directly to bear big strain.The two ends of slightly larger in diameter, the protection steel pipe 6 that is of convenient length are set in an end of described two first steel pipes 3; the other end of first steel pipe 3 is sleeved on an end of described second steel pipe 2; fiber grating 1 is passed first steel pipe 3, second steel pipe 2 and protection steel pipe 6; the grating grid region is in protection steel pipe 6 centers; be fixed on fiber grating 1 two ends in the groove of described two second steel pipes 2 with glue; second steel pipe, 2 overcoat thermal shrinkable sleeves, 5 protection fluting positions, described fiber grating 1 two ends tail optical fiber is drawn by the other end of described two second steel pipes 2.

The steel wire 7 at connecting cylinder position effectively is connected in susceptor design by fiber Bragg grating strain sensor and the cable, as shown in Figure 5, the stressed of steel wire will be delivered on the fiber grating effectively in the cable, thereby monitor the stressing conditions of steel wire by the variation of real-time monitoring fiber grating centre wavelength.Arrange that by fiber-optic grating sensor suitable on the steel wire in the cable it is stressed with local silk to realize taking into account simultaneously the whole stressed of cable.

Claims

1. intelligent cable fiber grating strain sensor; it is characterized in that described sensor comprises fiber grating (1); first steel pipe (3); second steel pipe (2); protection steel pipe (6) and bearing (4); described protection steel pipe (6) has one; first steel pipe (3); bearing (4) and second steel pipe (2) all have two; two first steel pipes (3); two bearings (4) and two second steel pipes (2) are symmetrically arranged in the right and left of described protection steel pipe (6); wherein the diameter of second steel pipe (2) is less than the diameter of first steel pipe (3) diameter less than protection steel pipe (6); axially grooved in the middle of described second steel pipe (2); the perforation of bearing (4) upper area; passing the perforation of described bearing (4) upper area in the middle of first steel pipe (3) is connected on the bearing (4); the two ends of protection steel pipe (6) are set in an end of described two first steel pipes (3); the other end of first steel pipe (3) is sleeved on an end of described second steel pipe (2); fiber grating (1) passes second steel pipe (2); first steel pipe (3) and protection steel pipe (6); the grating grid region is in protection steel pipe (6) center; fiber grating (1) two ends are fixed in the groove of described two second steel pipes (2) with glue; second steel pipe (2) fluting place overcoat thermal shrinkable sleeve (5), described fiber grating (1) two ends tail optical fiber is drawn by the other end of described two second steel pipes (2).