Study On Remote And Real Time Auto-monitoring Technology For Cable Tension Of Masangxi Yangtse River Bridge

Cable system is the main component which support the gravitation of cable stayed bridge. It has been an important part to analyze bridge's health that monitoring cable tension. The Masangxi Yangtse River Bridge is a long span cable-stayed bridge with two towers, as one of two important projects of Chongqing circular high-speed highway. Therefore, it can be of realistic significance to monitor its safety status when it works. Because that stochastic power vibration-frequency monitoring cable tension without advance fixing sensor and interrupting traffic, it is the most economical measurement. But it is difficult to get the characteristic spectrum of cable vibration. So there is some one to do this work repeatedly. Software could get vibration signal and analyze spectrum instead of the technician. There are some shortages in intellectualized software. The main work of this thesis includes:　①To discuss in details all kinds of factor which infect cable tension ,and analyzing the cable sport. To point out the connection between cable tension and base frequency and the expressions is given.　②On the basis of analyzing cable vibration , it's pointed out that the characteristic of vibration signal spectrum and the compute means for auto-identify base-frequency. And analyzing the infection with FFT。　③According to design purpose for cable tension measurement of The Masangxi Yangtse River Bridge. The hardware is designed. Considering the characteristics of vibration signal of cables, the technical and implementary strategy to the parts of which constitute the hardware is discussed.　④Besides the means to debase the yawp by lowpass and average arithmetic. On the basis of analyzing lower frequency noise, to point out: the frequency of noise and syntony signal is close and the distance between noise and syntony signal on the frequency axes is no more than half of base-frequency. It is put forward that auto-identify base-frequency when low frequency noise existing The datum which come from chronically monitoring for cable tension indicate that the monitoring system could accurately and effectively auto-identify base-frequency from spectrum of vibrancy signal, and it is stable and reliable.