Experimental Study on the Dynamic Buckling of Cylindrical Tanks : Comparison Between Static Buckling and Dynamic Buckling : Solid-Mechanics, Strength of Materials

Buckling failures are often observed in tanks subjected to seismic load. In this paper, dynamic buckling is studied, using small, plastic cylindrical tanks made of polyester sheets. Static buckling tests on the fluid-filled tanks subjected to lateral load, and dynamic buckling tests under harmonic excitation using a shaking table are carried out, and the buckling modes are compared. The stress resulting from the frequency response (the circumferential wave numbers n=1 for horizontal excitation and n=0 for vertical excitation) is calculated using an axi-symmetric shell finite element program, which includes the effect of fluid structure interaction. Static buckling stress criteria are applied to the above calculations in order to predict the occurrence of buckling. The predictions are compared with the test results and they prove to be fairly satisfactory in the restricted region the natural frequency of the fundamental mode.