Research On Health Monitoring Andassessment Method Of The Existing Concrete Cable-stayed Bridge

The Cable-stayed Bridge in the past 70 years has been booming, However, the existing concrete bridge, from the use of current situation,Most used in good condition, but there are a large number of bridges because of the lack of design and construction, material performance degradation, overloading operations and natural disasters, resulting the variety of structural damage occurred during the shorter using period, Including: linear change across the bridge, girder or bridge tower concrete cracking, cable rust and broken, expansion joints, drainage system damage and so on.The large bridge is a country's economic lifeline, the huge investment and significant, If the bridge's function degradation even the implied security risks can not be detected that will lead to major security incidents. Therefore, the health monitoring and state assessment of the existing bridge under the normal operation has become more and more attention. Meanwhile, the assessment can determine the bridge's current work state, and provide decision-making and guidance for the bridge's management.Based on analytic hierarchy process, This paper study a assessment method of the existing concrete cable-stayed bridge.Mainly in the following aspects:First, briefly introduced the existing concrete cable-stayed bridge's characteristics,the health monitoring and state assessment's purpose and significance, and summaried the several commonly used assessment methods at home and abroad;Second, explained the basic principle of AHP, and based on the《Highway Bridge Maintenance Specifications》(JTG H11-2004) and the characteristics of the cable-stayed bridge,using AHP Established the hierarchical structure model of the existing concrete cable-stayed bridge;Third, briefly introduced the basic principles of benchmark finite element basis that Simulation each component of cable-stayed bridge, established finite element model of Lijiatuo Yangtze River Bridge. Analyzed the structural dynamic response and under the typical load combinations the static structural characteristics;Then, as Lijiatuo Yangtze River Bridge the engineering background, described the existing concrete cable-stayed bridge monitoring program. determined the threshold value of each index and the corresponding weight of the measuring point;Finally, taking part of the measured data of Lijiatuo Yangtze River Bridge discussed in detail correctness and practicability of the AHP assessment application based on variable weights principle under the cable-stayed bridge operating conditions.