Analysis of Tall RC Chimney as per Indian Standard Code

Reinforced chimneys are used in Power plants to take the hot and poisonous flue gas to a great height. They are tall and slender structures, designed mainly to resist the lateral forces like wind and earthquake as well as the thermal stresses of the flue gas. An attempt is done to understand the variation of lateral deflection at the top of the chimney, by varying the height of chimney above 275 m. CED 387892 Code of practice for design of reinforced concrete chimney (Third revision of IS 49981992 [Part I]) is used for the analysis. The location selected for the study is Bellary in Karnataka. Along wind and temperature are only considered for this study. Sufficient amount of reinforcement is provided to resist the bending moment in the vertical direction and horizontal loops are provided to cater for the horizontal shear and temperature gradient. A total of five models are selected for five different heights and the analysis and design are done. ANSYS software was used to do the analysis. All the models were analyzed and the lateral deflection was calculated.