| Structural Health Monitoring(SHM)has been the focus of researchers all over the world. And FBG has become one of the most important sensing element in SHM due to its advantages such as high precision, high durabilities, quasi-distributivesensing, electric-magnetic resistance, small size, convenience to integrate sensing network, etc. With the economic developed in China, investment in infrastructuresis almost half of that in the whole world, which provides opportunities for SHM and also FBG sensing techniques. In this paper, some key techniques of practical applications of FBG sensors have been studied as followed.The first chapter first elaborated the selected topic basis is the early construction diagonal cable bridge, because the being operational time is excessively long, appeared has had the material to corrode, the material performance to degenerate, the crack initiation and the development, the fatigue damage and so on a series of structure damage question, These hidden dangers like do not solve, will present the big accident, therefore, needs to carry on the health examination to them. Next elaborated domestic and foreign the question which as well as appears to the health examination's research present situation, namely in structure health monitor and damage recognition a key question, How is to eliminate the environmental factor influence which, the noise and the test error in the actual signal mixes with and so on, obtains the reflection structure itself condition small change damage information, the monitor instrument which this article uses in the experiment, although also has the problem so forth, But has technically made the improvement, causes the environmental factor and so on error which causes to be smallest. Elaborated the selected topic goal, the significance, the research technique and the technical route once more and so on. The selected topic goal is needs to have the hidden danger the bridge to carry on the health monitor, evaluates its state of health, The significance namely prevents accidents before they occur, the reduced operation expense, to cause the fiber grating monitor technology maturer and so on, the research technique for using the fiber grating new technology, the new monitoring facilities and so on to carry on the monitor to the bridge.The second chapter mainly elaborated the health observation system's composition, the current health observation system existence question, the health monitor strategy analysis and the frame design. The health monitor mainly has the sensor system, the data acquisition and the analysis system, the monitoring center and realizes the diagnosis function each kind of software and hardware composition, And has carried on the thorough analysis to two main sub-item sensor system and the sensor system. Afterward has excavated the current health observation system existence question, namely the bridge health observation system is only restricted in the data acquisition, the preservation, but in carries on the scientific management, the science to the monitor data The reasonable appraisal bridge, the diagnosis structure healthy condition, carries on aspect and so on appraisal using the monitor data to the bridge state of health research and the application obvious insufficient, namely also waits for the deep research in the health observation system intellectualization aspect, simultaneously, this article proposed the countermeasure on these insufficiencies. Once more, carried on to the health monitor strategy analysis and the frame design has analyzed and proposed design criterion as well as the bridge health observation system design procedure and so on. The third chapter this article first elaborated the optical fiber intelligence health observation system's constitution, namely optical fiber intelligence health observation system mainly by the following three parts of constitutions: Optical fiber sensor system, signaling and gathering system, data processing and observation system. And has analyzed each system's in overall system function and the function, afterward elaborated the optical fiber sensor performance superiority, after that also introduced several kind of sensors, introduced the optical fiber position transmitter and the Bragg diffraction grating with emphasis (Bragg grating) the strain sensor. And to the optical fiber sensor's principle, the characteristic and the current application's condition has carried on the introduction. In addition, but also carried in the optical fiber sensor's installment and the signal transmission introduced that the installment introduction caused us to instruct the question which how to use, but the signal transmission's introduction made us to understand that the data acquisition project, was advantageous for the analytical error and so on. Afterward, has carried on the analysis to the optical fiber health monitor's application domain, and analyzes Optical fiber health monitor technology present existence question.Simultaneously also tells us, although the optical fiber health observation system's application also has some actual problems to need to perform to consider, but it gives the entire sensing domain the development to bring the new turning point; At the same time, more precise and the sensitive measuring technique means that we are more thorough to objective world's understanding, will certainly to bring the related domain science and technology in the near future the development. The fourth chapter the content is to the Bengbu Huaihe River bridge fiber grating health observation system project summary. First did to the project introduced briefly that let us have a perceptual understanding to the project, next proposed based on the project characteristic the monitor plan, namely aimed at the Bengbu Huaihe River bridge plant disease characteristic and the reinforcement maintenance work key point, determined the slanting back guy Tension jail Measured that the king post stress monitor and the king post close up the section prestressed rinforcement stress monitor for the Bengbu Huaihe River bridge fiber grating health observation system's primary coverage. Temperature sensor's build main consideration temperature load has the season temperature difference and the sunshine temperature difference characteristic, guaranteed that the temperature sensor may monitor the ambient temperature and the temperature in component's graded distribution. Based on this, accumulates according to the fiber grating health observation system's rank and the Bengbu Huaihe River bridge damage specifically especially The spot, carries on the optimization to sensor's build position and quantity. In line with the technological advance, the economy are reasonable, the perform reliably, the long-term stability, satisfies the monitor request the goal to choose sensor's type.The union to the Bengbu Huaihe River bridge's unique feature, selected 44 slanting back guys, 6 king post sections, 10 prestressed rinforcements to take the monitor object; Monitors sensor's type according to the different monitor object's concrete feature selection; And to built sensor's position and quantity has carried on the optimization, Summarizes finally the above content for the system implementation plan. In the system implementation process, unified the former experience and the project scene special details deep research each type sensor's build craft, formulated the series both the science to be reasonable and the easy and feasible sensor build craft. Closes up section prestressed rinforcement Zhang La in the Bengbu Huaihe River bridge span, to become the bridge to test as well as to be open to traffic the operation three crucial stages, The dependence in each stage already the work achievement which completes, we have carried on the monitor to these three stage bridge's condition, has obtained the massive precious data. At present, the Bengbu Huaihe River bridge fiber grating health observation system's implementation work has completed comprehensively, the system enters the online real-time monitor the running status.
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