Effect of Wrinkling Allowance in Tensile Membrane Structures

Wrinkling is a common phenomenon in tensile membrane structures (TMS), which are widely used in architectural applications because they are lightweight, flexible, and have an aesthetic appeal. However, wrinkling can affect the stress distribution and overall performance of TMS. Current practices and literature aim to completely prevent wrinkling by ensuring that the membrane remains under tensile stress (in all directions) throughout its service life. Achieving this "no wrinkling" state often requires prestressing the fabric to higher levels, thereby increasing the stress even before any external loads are applied. Therefore, this action has a potential to reduce the external load carrying capacity against tearing failure. On the other hand, allowing excessive wrinkling may compromise the aesthetics of the structure, although the presence of wrinkles does not necessarily indicate structural damage. Therefore, allowing a controlled amount of wrinkling can help prevent membrane stresses from exceeding permissible limits under load, while maintaining aesthetic and functional integrity. This paper investigates the impact of tolerating some degree of wrinkling on the limit state of tearing of tensile membranes. The objective is to develop a deeper understanding of the relationship between the spread of wrinkles and the stress thresholds, providing insights that can inform design strategies and ensure structural integrity. Case studies are presented, covering both fundamental and complex TMS shapes under various load cases.