The two basic types of towers are briefly described with their diversity in form, construction, and function illustrated by a number of recently constructed structures.
The general theory of wind pressure for aerostatic effects and the empirical-shape factors reported for common structural members are presented. Composite shape factor-solidity ratio relations for square and triangular towers are derived through the use of test data on trusses for aerostatic drag, shielding, and yaw effects. The validity of these relations as reasonably conservative design tools is confirmed by a comparison with test results. Various foreign and American codes are compared relative to aerostatic wind-loading recommendations on tower structures.