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This paper presents an analytical study on the critical dynamic buckling load of cylindrical shells with arbitrary axisymmetric thickness variation under uniform external pressure which is a function of time. Based on the Donnell simplified principle, the equilibrium and compatibility equations of cylindrical shells with arbitrary axisymmetric wall thickness under dynamic external pressure were derived. By using the method of separation of variables, the equations were transformed into ordinary differential equations in nondimensional form. Combining Fourier series expansion and the regular perturbation method, as well as the Sachenkov–Baktieva method, analytical formulas of the critical buckling load of cylindrical shells with arbitrary axisymmetric thickness variation under dynamic external pressure that varies as a power function of time were obtained. Using these analytical formulas, the critical dynamic buckling load of cylindrical shells with linearly and parbolically varying thickness were computed. The influences of thickness variation parameter and loading speed of external pressure on the critical buckling load were also discussed. The method was also applied to cylindrical shells with a classical cosine form thickness variation, by introducing the reduction factor of critical dynamic buckling load. The buckling capacity of these cylindrical shells under dynamic external pressure was discussed considering the effects of loading speed and thickness variation parameter.

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A series of seismic table tests about the large steel cylindrical liquid storage tank models with floating roof were taken in this study. Horizontal and vertical direction seismic excitations were input respectively to the experimental structure system under different working conditions to test and analyze the seismic response behavior. The effects of various factors, such as the liquid surface height, the floating roof, the different wave amplitudes and frequencies, as well as their combined effects on the seismic dynamic response were obtained. The absolute displacement and the uplift response behavior law of the test models were obtained under different conditions. It was concluded that not only uplift value but also the absolute displacement of the tank bottom should be considered. And it should be noticed that a critical input frequency exists during the model response changing with frequency. In addition, important factors in experiment were described systematically in this article, for example, the experimental equipment selection, the experimental method, the tank model design, the laser displacement sensors, the data acquisition, the measurement point layout method, seismic excitation input method and so on. A reliable basis could be provided for theoretical analysis, structural design and computer numerical simulation research through this investigation.