Research Of Optimal Placement Of Sensors For Health Monitoring System Of Long-Span Suspension Bridge

Bridge structural health monitoring system is a set of structural monitoring, system identification and structural assessment of an integrated monitoring system.health monitoring system in general can be divided into the following subsystems:sensing system, signal acquisition system. data processing and analysis system. assessment system. data management system.communication and alarm systems. Its significance lies in a combination of a number of areas of knowledge, has greatly expanded the connotation of the bridge structure inspection areas, improve the reliability of the forecast evaluation.The sensor is a form of information into another form of information the device with the detection of components.The sensor system is an important part of the bridge structural health monitoring. Arrangement of sensors because the structure of operational status and economic reasons, in all degrees of freedom of the whole bridge structure is neither practical nor can not, thus showing the importance of the optimization of the sensor layout problem. Laid the lowest number of sensors to obtain the most reliable and most comprehensive health information of the bridge structure, which is the goal of optimal sensor placement algorithms.The main content of the thesis has the following several aspects.(1) Based on the finite element software Midas,the paper establish calculation model of Guan Tou Ba suspension Bridge, and analyze static characteristic and dynamic characteristics of the bridge.(2) Analyzed the vibration property of the bridge, the first modal shape for main girder is symmetric lateral bending, vibration frequency of main girder is higher, the torsion of truss center and cross section center of mass not completely together, make truss can produce torsional coupled.(3) In the process of using MAC standards and optimizing arrangement the sensor for the dynamic characteristics monitor introduced QR decomposition, and selected2-norm larger node position as a sensor initial configuration, can quickly get optimal layout, and can ensure the data that is collected by limited measuring orthogonality.(4) According to Guan Tou Ba suspension Bridge finite element model action force calculation and analysis of the results calculated, the paper optimize the sensor layout of suspension bridge health monitoring.