The column based hyperbolic reinforced concrete cooling towers are ecstatic in aesthetics, gigantic in nature and complex in geometry. The evolution of "Design and Constructions" of these towers have come long way in India and as on date, 141.0m height Panipat Natural Draught Cooling Towers are the tallest commissioned towers in the country. In the past, before the computer revolution, the analysis used to be done only for membrane forces in shell elements. However, as the towers grew in stature beyond 100.0m height clubbed with infamous episode of Ferry Bridge cooling tower in UK emphasized the relevance of bending analysis coupled with membrane forces. Invariably it is found that the structural criticality in NDCTs is due to the wind induced dynamic forces, which compounds the complexity of the above analysis. The following aspects, 1. the peculiar geometry, 2. the real boundary conditions, 3. stress, temperature and time dependent behaviour of constituent materials including composites, 4. space-time dependent loads including random excitations, 5. different types of behaviors, such as linear, dynamic stability, etc., of structure to be examined, make the Finite Element Analysis apt and natural choice for the NDCTs. In the paper followed, the complexity of wind induced forces and rationale behind the applications, the progression from membrane analysis to bending analysis, the simple practice of descretising Finite Element Model for NDCTs and finally the illustrations and discussions on FEA for Panipat NDCT, the tallest tower in India as on date is discussed in length.
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