Scaling relations in the collapse of elastic icosadeltahedral shells under uniform external pressure

We discuss collapse of icosadeltahedral shells subjected to uniform external pressure. We demonstrate that there is a universal collapse pressure curve. The parameter that uniquely determines the collapse pressure is shown to be the Foppl-von Karman number of the non-pressurized shells. Numerical results are interpreted in terms of buckling instabilities of spheres and cylinders under hydrostatic pressure.