Forced vibrations of silos leading to buckling

The large-amplitude force vibrations of steel thin-walled silos when empty are investigated. The basic geometry configuration modelled is a cylinder c lamped at the bottom with a top conical roof. Wind pressure distributions a re assumed as non-axisymmetric in the circumferential direction and with a rectangular impulse or step distribution in time. Instability is identified from finite-element computations of the time response of the shell using a criterion due to Budianski and Roth. Results are computed for silos made w ith plain as well as with corrugated sheets, and the influences of geometri c imperfections and the stiffening due to the roof are included in the anal ysis. The problems are also modelled with static pressures using both conti nuation techniques and bifurcation analysis from a linear fundamental path. Additional results have been obtained to estimate the dynamic buckling loa d for step loading using energy procedures. All results are computed using finite-element codes developed by the authors. (C) 1999 Academic Press.