In order to investigate the vibration fatigue characteristics of thin-walled stiffened structures under random vibration loading

a random vibration test was carried out.The structure inherent frequency and modal response were obtained by using the hammering and the sine-sweep method

the cracking time and pattern were recorded.The method for obtaining the fatigue life curve under random stress by revising the fatigue life curve under equal amplitude stress was deduced.Then based on MSC/Patran&Nastran simulation finite-element software

the dynamic response on the fatigue danger point and its random vibration fatigue life were obtained

the effects of creating model methods on the inherent frequency were studied

and the change of damping impacts on the vibration properties was analyzed.The results show that the model stiffness with using mixed element are much closer to the actual structure than only solid or shell

the modal responses under the nonlinear damping are more consistent with the sweep results.Finally

the calculated fatigue life and failure position are in good agreement with the experimental results.