Experimental and numerical analyses of a full-scale legged storage tank subjected to dynamic loading

Legged wine storage tanks have sustained significant damage during past earthquakes, but there is limited full-scale experimental data available to support understanding of their seismic behaviour, particularly under different anchorage and operating conditions. The dynamic response of a full-scale legged wine storage tank was investigated through a combination of shake-table testing and finite element (FE) modelling. Experimental testing was conducted on an empty tank subjected to impulse excitation, harmonic loading, and earthquake ground motions derived from the 2011 Christchurch (M w 6.2) and 2010 Maule (M w 8.8) earthquakes. Companion FE analyses were performed using ANSYS to investigate both anchored and unanchored configurations in empty and full operating conditions. Analysis of the impulse test results indicated that the fundamental frequency of the tank increased with increasing fixity to the shake table. The earthquake-record test results showed that anchorage significantly influenced strain distribution, with anchored tanks experiencing greater wall strains and lower leg strains compared with unanchored tanks. Numerical modelling showed that anchorage increased wall strains, particularly for the full tank, while the presence of liquid reduced lateral displacement and uplift in the unanchored tank. The findings provide insight into the influence of anchorage conditions and operating fill levels on the seismic performance of legged tanks, with implications for seismic design.