Finite element analysis of column supported hyperbolic cooling towers using semi-loof shell and beam elements

摘要

In most of the early works related to the analysis of hyperbolic cooling towers, under either dead or the wind loads, only the tower shell was considered in the analysis and a continuous boundary condition in the form of fixity of the base of the shell was con- sidered. However, the tower shell is supported by columns in the form of A-frames. In order to consider realistic boundary con- ditions, it is essential to consider the supporting columns in the analysis along with the shell. The present study considers this problem and an attempt has been made to represent the tower shell by semi-loof shell elements and the supporting columns by semi-loof beam elements. The column ends are assumed to be fixed at their bases. The analysis has been carried out for only the dead load. The results have been found to compare with those of Gould 'Finite Element Analysis of Shells of Revolution', Pitman, London, 1984, and lyer and Appa Rao 'Studies of stress concen- tration at shell--column junctions of hyperboloid cooling towers', Comp. Struct.. 1990, 34, 191 --20. Hoop forces have been found to have altered significantly in the lower portion of the shell near the column--shell junction. Moreover, the proposed model gives a bet- ter physical representation of a column supported hyperbolic cool- ing tower.