Numerical evaluation of the ultimate load of concrete funicular shells of circular plan

Abstract

A special type of shell structure – a concrete shallow funicular shell of circular plan – is considered in this paper. Funicular shells carry their dead weight only by in-plane compression forces. Numerical analysis of funicular shells was performed using the non-linear finite-element method, considering both geometric and material non-linearities. A circular-plan concrete funicular shell unit was also constructed and its ultimate central concentrated load is determined. The ultimate load of the shell unit predicted by the numerical model was very close to the experimentally determined ultimate load, thus confirming the validity of the numerical model. The numerical results revealed the effect of the base radius and the thickness of funicular shells on their stiffness and ultimate central concentrated load. It was found that an increase in the thickness of funicular shells increases their ultimate uniformly distributed load (UDL) while an increase in the base radius decreased the ultimate UDL, linearly for the former and non-linearly for the latter.