Study And Application Of The Sensors Optimal Placement Depends On The QR Decomposition Method And The Effective Independence Algorithm In The Large-scale Steel Structure Engineering Health

The structure health monitoring has been one of the research focus, and the sensors optimal placement is the key step of it, and there are many monitoring data collection methods, this article compared the principles, classifications and the characteristics of the fiber Bragg grating sensors, vibrating wire sensors, piezoelectric sensors and some other kinds; according to the actual project situation, the vibrating wire sensors were chosen for this project, also provided good reference for similar projectsUsing the mathematical description, combining the structural dynamics and the modal analysis theory, the theoretical principles of the vibration sensors optimal placement in the health monitoring are basically elaborated; we introduced some representative sensors optimal placement principles, analyzed the basic principles of the minimum error-identify guidelines and the optimal placement principles depend on energy and modal assurance.Eight classic optimization calculate methods (the effective independence algorithm, the QR decomposition method, the effective strain energy method, genetic algorithm, the MAC method, Guyan model reduction method, modal kinetic method, and singular value decomposition method) were Studied. With comparing their characteristics, we thought using both the QR decomposition method and the effective independence algorithm to some large-scale structure engineering health monitoring sensors optimal placement can be more accurate and reduce the iterations of the effective independence algorithm, it is simply operated and high-efficiently calculated.Use the research achievement to optimize the vibration sensors of the steel bleachers of the Grand Theatre Concert Hall. Firstly using the great finite element analysis software ANSYS to establish the model, output the first10vibration mode matrix of the steel bleachers; secondly, using the MATLAB language to execute the QR decomposition to the vibration mode matrix, first choosing sensors placement; to this chosen placement, using the effective independence algorithm to make the final sensors placement; lastly using the model assurance criterion, drawing the full model and the optimized model MAC matrix histograms, verified that this optimization scheme has good reliability, also provided good reference for similar projects...