Effect of planar anisotropy on wrinkle formation tendencies in curved sheets

Wrinkle formation tendencies in the form of short-wavelength shallow buckling modes are investigated for sheet materials exhibiting planar anisotropy. The critical state for the onset of these short-wavelength shallow modes are determined from plastic bifurcation theory. A local analysis is performed by considering the current deformed state of a sheet element in a doubly-curved, biaxial plane stress state. The planar anisotropy is prescribed using recently proposed anisotropic yield criteria. Parametric studies are performed to assess the effects of the various material and geometric parameters on wrinkling.