Seismic assessment of flat-based and legged wine tanks : application to Portugal

Details

Supervisors

Saraiva Esteves Pacheco De Almeida, João ; Costa, Alexandre

Faculty

Ecole polytechnique de Louvain

Degree label

Master [120] : ingénieur civil des constructions, à finalité spécialisée

Abstract

enDesigning structures under seismic action is challenging, especially for liquid storage tanks, whose response is strongly influenced by the motion of the stored liquid. This is particularly relevant for wine tanks, where the economic loss of content can be more important than the structural damage itself. This thesis presents a methodology to assess the seismic stability of stainless-steel wine storage tanks. Two configurations representative of winery applications are analysed: a flat-based tank and a legged tank. Analytical models are first developed to estimate the global seismic demand, mainly in terms of base shear force and overturning moment. Simplified numerical models are then implemented in SeismoStruct using an equivalent spring--mass representation of the liquid components, allowing time-history analyses without a full finite element fluid--structure interaction model. Specific limit states are defined for each tank typology, based on the expected damage mechanisms. For the flat-based tank, the assessment focuses on shell buckling and anchorage-related mechanisms. For the legged tank, sliding, overturning, uplift, leg buckling and base punching are considered. Fragility curves are then developed from incremental dynamic analyses to evaluate the vulnerability of the tanks under increasing seismic intensity. The methodology is applied to a case study related to a future winery project located near Portimão, Portugal. The results show that the flat-based tank remains safe for the selected seismic inputs, although the anchorage system remains the most critical component, especially regarding anchor buckling. The legged tank is more sensitive to support-related mechanisms. The serviceability overturning criterion is reached, indicating the beginning of rocking and uplift, while leg buckling governs the ultimate limit state verification. Overall, both configurations can be adapted to the seismic conditions of the considered site, but the support system of legged tanks requires particular attention. The analytical model provides a useful first estimate of the global seismic demand, while the numerical model allows a more detailed verification of local response quantities. The proposed framework therefore provides a practical basis for the seismic assessment of wine tanks and can be adapted to other geometries, support conditions and mitigation solutions.