Simplified approaches to the evaluation of the across-wind response of chimneys

Abstract A model for the prediction of the response of chimneys to vortex shedding is outlined and the major characteristics of solutions employing the model are described. Simplified equations suitable for routine office use are derived. For modes other than the fundamental the simplified forms require a knowledge of the mode shapes and frequencies but, for the fundamental mode, it is shown that an equivalent static load can be defined with a knowledge of the frequency only. The application of the simplified forms is demonstrated with sample calculations presented for two chimneys. The results of the simplified forms are shown to be slightly conservative in relation to estimates obtained using the detailed approach.