Design of Browns Ferry Chimney

The design of a chimney used to dilute and disperse slightly radioactive gases at TVA’s Browns Ferry Nuclear Plant is described. The chimney is designed for 100 mph winds, earthquakes, direct hits by tornados, and a resonant wind force. Due to the proximity of the chimney to important structures, any possibility of it breaking near its based and falling on those structures had to be eliminated. A weaker section is therefore designed into its upper portion. A catastrophic wind force would then collapse the upper portion prior to a possible destruction of the lower part. Both the working stress design specified by the chimney code and an ultimate strength design are used.