Abstract: In order to study dynamic reliability of storage tank structure under random wind load, with a 300 m³small and medium-sized vertical cryogenic tank as research object, pulsating wind speed time series and pulsating power spectral density function of wind load were numerically simulated by using AR model. Then, a three-dimensional finite element model of storage tank was established by ANSYS, and dynamic analysis of the tank was carried out to calculate random response value of storage tank structure before all digital features required for its dynamic reliability under random wind load were obtained. Finally, dynamic reliability was calculated by using first transcendence mechanism. The results show that under the condition of maximum wind speed of 26.8 m/s 10 m high in 50 years, structure displacement and velocity response amplitude are relatively large and storage tank is comparatively sensitive to low frequency vibration when vibration frequency is 0.83 Hz. With the increase of service life, dynamic reliability of storage tank structure presents a negative exponential decline trend, which will drop to 71.46% when designed service life of storage tank reaches 25 years.

Key words: vertical cryogenic tank, wind load, auto regressive (AR) model, first transcendence mechanism, dynamic reliability