On the buckling analysis and design of silos and tanks

Abstract

Buckling considerations arise in the design of steel silos and tanks because the slender shell wall is subjected to compressive stresses, most commonly from the action of wind on the empty structure causing circumferential stresses, and combinations of wall friction forces, roof loads, non-uniform filling and discharge, and non-uniform settlement of the foundation causing meridional stresses. In this paper, recent research work of the author and graduate students relevant to buckling behaviour is briefly reviewed. Problems relevant to buckling behaviour, and which arose in several major tanks and silos with which the author was concerned either at the design stage or arising from operational problems, are discussed. The buckling behaviour and design of slender steel silos and tanks has been reviewed, with particular reference to buckling under wind loading, and under meridional compression. The benefits to be obtained by refined finite element analysis at the design stage have been emphasised, and several examples of buckling phenomena in the design of major structures reviewed. The occurrence of uplift of large emoty tanks under severe wind loadings has been detected. A simplified design method for wind buckling has been given, which includes an approximate consideration of the effects of imperfections, meridional end restraints and form of the wind pressure distributions. Situations under which meridional compression can govern the design have been explored. The beneficial effects of a bulk solid content against buckling have been investigated.