Structural analysis and design criteria of circular prestressed concrete tanks

Abstract

The present work is based on the structural behaviour of circular prestressed concrete tanks. In this study, an analytical linear elastic model that considers the soil-tank interaction under axisymmetric loads, taking into account the movement capacity of the wall-to-base connection, is developed. Parametric studies are carried out in order to find the effects on the wall of all parameters governing the stiffness of the wall-to-base connection. Different methods to analyse the main forces of a circular prestressed concrete wall with free edge at the top and a generic wall-to-base connection are presented, which generalize some simplified methods conventionally adopted. A procedure for the determination of a circumferential prestressing function is suggested, in order to ensure a suitable residual compressive stress in the circumferential direction when the tank is full. Furthermore, some criteria about the design of the wall-to-base connection are proposed, taking into account both the tank geometry and the prestressing criteria.