Lateral stiffness and preliminary design methodology of twisted diagrid tube structures

Abstract

SummaryTwisted forms have been widely employed in high‐rise buildings in recent years. The diagrid structural system is particularly suitable for twisted buildings because of its large lateral stiffness and unique architectural esthetics, but little research on twisted diagrid tube structures is currently available. This paper studies the influence of diagonal angle, twist rate, aspect ratio, corner column, and plan form on the lateral stiffness of twisted diagrids, and the optimal diagonal angle range is determined. Considering the stiffness and strength criteria, the design methodology of diagonal sizes of twisted diagrids is proposed, and the methodology is validated by finite element analysis. In addition, this paper presents a novel configuration of twisted diagrid, that is, the twisted diagrid with asymmetric diagonal angles. The influence of the left‐ and right‐inclined diagonal angle on the lateral stiffness of twisted diagrids is investigated. It is found that twisted diagrid structure with asymmetric diagonal angles exhibits larger lateral stiffness than the symmetric case. The results in this paper are useful for engineers to determine the configuration and diagonal sizes of the twisted diagrid tube structures.