Instability of thin circular membranes subjected to hydro-static loads

• We studied the instability behavior of circular thin membranes hydro-statically loaded.
• We used a Mooney–Rivlin material model in a membrane FEM formulation.
• We noted a significant difference in response when loading from above or below.
• The instability response was shown to be highly parameter dependent.
• Advanced generalized path-following allowed the parameter investigations.

Membrane structures subjected to hydrostatic load are prone to undergo large deformations and lose stability. This paper investigates different instability phenomena for a thin, circular and initially flat and horizontal membrane. The Mooney–Rivlin hyper-elastic model is used to provide the material description. An axisymmetric and a 3D model have been set up to show the large deformations and instability behavior with different parameter settings. Numerical examples show that the methods developed are capable to describe the deformation dependent loading conditions and the instability phenomena. The numerical simulations show fundamental differences in the response and instability behavior when the horizontal membrane is loaded from above or below. The parameters of fluids and membranes and the means for introducing the pressure are of essence for interpreting the instability behavior.