Seismic response of rectangular liquid retaining structures resting on ground considering coupled soil-structure interaction

Seismic response of water tanks resting on ground has been a topic of considerable research in academics as well as energy and infrastructure industry. In many cases, it remains essential that they remain functional even after a major ground shaking. State of the art adapted in different national and international code usually recommends a simplified mathematical model that in many cases digresses from field reality. A three dimensional analysis of the tank plus fluid and foundation soil is surely possible based on finite element analysis. However, in most cases, such exhaustive analysis is done away with, often due to lack of supportive software to tackle such problem, but more out of economic and schedule compulsion, where in many cases engineers do not have the luxury to carry out such expensive analysis, to remain competitive in the market. Thus, a search for a better and more realistic model than what is in vogue is still in quest for this particular problem. Present paper attempts to present a mathematical model based on Lagrange's formulation and adapting Galerkin's technique that circumvents many of the problems as cited above.