Numerical and Theoretical Investigation into the Global Stability Behaviour of Glulam Gridshells Stiffened by Prestressed Cables

As a low-carbon and lightweight material, glulam is increasingly being used in spatial gridshells. However, these glulam gridshells are prone to instability owing to the material properties of glulam. In this study, to enhance the overall stability behaviour, a prestressed cable system was introduced to the ordinary glulam gridshell to form a novel prestressed cable-braced glulam gridshell. Extensive finite element simulations were conducted to examine the mechanical performance of these novel gridshells. This paper analyses how variations in structural parameters impact the stability performance of the shell. Furthermore, an approximate formula is developed to assess the load carrying capacity. This formula is established by integrating theoretical derivations with numerical simulations. We have thus demonstrated that the stability behaviour of traditional glulam gridshells can be significantly improved by the introduction of prestressed cable systems, and the proposed evaluation formula is accurate enough for the load carrying capacity prediction of prestressed cable-braced glulam gridshell.