Abstract: A large number of platforms in my country's waters have entered the middle and late stages. The management of these aging platforms， especially structural safety， has become the focus of the current operator's relationship. Vibration monitoring is used. The safety assurance of the jacket platform structure is a new type of means， which provides early warning through fundamental frequency changes and displacement changes. The fundamental frequency change is realized by shorttime Fourier transform and wavelet spectrum analysis methods. In addition， a method of correcting the evaluation model through vibration measurement and then performing post evaluation is proposed.

Key words: vibration monitoring, shorttime Fourier transform, wavelet spectrum analysis, post evaluation