Optimal design of double-level guyed towers against buckling

Abstract

This paper is concerned with the optimal design of double-level guyed towers against buckling with a given material volume. The double-level guyed tower is simplified as a lateral braced column considering the pre-tensioned cable stiffness. The buckling criterion for double-level guyed towers is then analytically derived based on a matrix stiffness method (MSM) that enables the use of one element per member for an exact solution. Optimal designs of double-level guyed towers under various base fixity factors are obtained through an optimization procedure involving two decision variables: the height ratio and the cross-sectional area ratio between the upper level and the lower level. Optimization results indicate that pinned-ended double-level guyed towers achieve their maximum buckling load at a height ratio of 1.19 and a cross-sectional area ratio of 1.19. In contrast, fixed-ended towers achieve their maximum buckling load with a height ratio of 0.70 and a cross-sectional area ratio of 1.13. Transitioning from pinned to fixed base conditions increases the maximum buckling load by approximately 1.52 times. Design recommendations for double-level guyed towers are further presented.