Analysis of Center to Edge Foundation Settlement of Atmospheric Storage Tanks

Abstract

Modern large capacity atmospheric steel storage tanks incur differential settlement of the soil foundations upon which they rest due to the Boussinesq effect [1, 2]. The difference in settlement between the center of such a tank and its edge generates membrane forces in the bottom plates. For good design, these forces should be limited below the bottom plate strength, and their radial component at the edge should be limited below the critical shell buckling shear force. To meet these requirements tank site improvement to reduce the anticipated differential settlement may occasionally be requied prior to the tank erection. An analysis for determining the membrane forces in the bottom plates based on the large deflection theory and the critical shell buckling forces as functions of tank properties and the foundation modulus is presented.