| Driven by the speedy progresses of science and technology as well as economy, city and roadway constructions in China experienced rapid development. Lots of super-scale bridges were constructed in riverside and coastal regions, western mountainous area and metropolises, connecting many places in all directions, becoming pivots and symbolic buildings of numerous cities and roadways. With the increases of service time and overloading vehicles, latent hazard and probability of super-scale bridge accidents are rising, severe bridge accidents influencing the national economy and the people's livelihood happened at times. Therefore, the subject of health monitoring, safety management and maintenance of super-scale bridges was presented by bridge management organizations and engineering units, hoping to monitor key parameters of bridge structures technologically, provide bridge safety evaluation rule, lengthen bridge structure life under the premise of safe service, so as to exert their social and economical efficiency maximally. Since the safety service of bridges is significant to social and economical developments, high and new technologies are applied to solve the difficulties of bridge safety service in developed countries successively, the research and application of bridge health monitoring system attract worldwide attentions, and has been rapidly developed in many countries in recent years. Being the most challenging subject in the 21st century, research of intelligent materials and structures system has important application potential in both military and civil fields, therefore using intelligent materials and structures technologies to solve the health monitoring and evaluation of key civil structures within their life cycles becomes world hotspot subject due to its great social benefit and economical value. At present, electromagnetic-based intelligent materials have been successfully applied to vibration mitigation and antiseismic controls of large-scale bridge structures in developed countries, application of fiber optic grating intelligent materials to the health monitoring of bridge structures has also been attempted, with achievements mainly limited to laboratory experimentation of monomial sensor.Currently, the crucial and key problem of the health monitoring system of bridge structures is to acquire bridge's crucial information chronically and reliably. With the merit of long-term reliability, the monitoring system based on fiber optic grating intelligent materials becomes preferred technology to construct long-term health monitoring system of bridge structures gradually. Since super-scale bridges occupy broad space and have many types of parameters to be measured, how to acquire those types of parameters needed by structural health monitoring of super-scale bridges chronically and reliably, by means of fiber optic grating intelligent materials and structures technologies, turns into a technological difficulty to be urgently overcome.Based upon advanced fiber optic grating sensing technology and theory of intelligent materials and structures system, this subject aims at establishing long-term health monitoring system of super-scale cable-stayed bridges, evaluating their safety by long-term structure information and successive testing. Financially supported by Key Project of the National Natural Science Fund, National 863 Program and Key Research Project of Hubei Province, with the long-term health monitoring systems of Wuhan Second Yangtze River Bridge, Wuhan Yangluo Yangtze River Bridge and Tianxingzhou Yangtze River Roadway-Train Bridge as engineering implementation background, focusing on fundamental theory, basic experiments and engineering practice of utilizing intelligent materials and structures system in bridge health monitoring, in this dissertation, relevant technologies of applying fiber optic grating intelligent materials and structures theory to bridges are studied, technologies of special fiber optic grating sensor testing system fabrication and network integration are discussed from the aspects of bridge structure load and traffic loading inspection. The research of this dissertation has been undertaken for three years, and several achievements have been certified.The principal contents of this dissertation are as follows:(1) The development of health monitoring system of large-scale bridge and its relevant technology is reviewed and summarized; experiences and lessens which could be used for reference are analyzed; fundamental configuration, principle, existing problems and key technological difficulties of long-term health monitoring system of large-scale bridges are illustrated.(2) Intelligent materials and structures system as well as relevant sensing testing technologies, especially the research state and trend of fiber optic grating sensing testing technology, are summarized. The fundamental concepts and configuration manners of fiber optic grating intelligent materials and structures, as well as the principle of its application in bridge health monitoring, are discussed for the purpose of presenting research targets and tasks of this subject.(3) Considering the characteristics of health monitoring system of large-scale cable-stayed bridges, employing the ideas of fiber optic grating sensing testing technology, and intelligent materials and structures, the difficulty of real-time inspection of cable force, strain of key cross-section, temperature, and heavy truck loading is solved.(4) Based on structure loading, environment and traffic load information acquired by long-term health monitoring system of large-scale cable-stayed bridges, and structural simulation, health evaluation system is established and corresponding evaluation index system is designed.(5) Previous research achievements are firstly applied to practical bridge health monitoring system, including Wuhan Qingchuan Bridge. The application results reveal that fiber optic grating sensor and relevant monitoring system could meet the practical engineering need of long-term health monitoring of large-scale bridges, including long-term structural parameter acquisition, testing accuracy, stability, and durability. It can be concluded that the elementary practical application of fiber optic intelligent materials and structures in bridge engineering is completed.
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