ANALYSIS OF FLUID STORAGE TANKS INCLUDING FOUNDATION-SUPERSTRUCTURE INTERACTION

An analytical formulation is developed to predict the flexural behavio r of a cylindrical liquid storage tank resting on an isotropic elastic soil medium, which is modelled as a half space. The interface between the plate foundation and the soil medium is considered to be smooth a nd continuous. The plate deflection function is assumed in the form of a power series expansion in terms of the radial coordinate. The proce dure accounts for the interactions between the tank wall and the plate foundation, and between the plate foundation and the soil medium. The principle of minimum potential energy is used to evaluate the unknown coefficients appearing in the assumed power series expansion and also the unknown interacting forces at the tank wall-plate foundation junc tion. Any number of terms can be considered in the assumed deflection function. Analytical expressions are obtained for the plate foundation deflections and radial moment, the contact stress distribution, the t ank wall displacements, and the tank wall stress resultants. The resul ts obtained compare well with the the effect of the various geometric and material parameters on the flexural behavior of the system.