Compression of Fluid-Filled Spherical Shells by Rigid Indenters

Two variational solutions were studied for large deflection of a fluid-filled hemispherical shell by a rigid cylindrical indenter. One solution is based on shell theory (including bending and stretching energy) and the other on a membrane model (stretching only). To study the transition from bending to membrane action, calculations are compared to load and fluid pressure data from experiments on water-filled rubber shells of various thicknesses. While bending effects dominate deflection as large as 20 percent of the radius for very thick shells (R/t ≥ 10), the results indicate that membrane stress is significant in thinner shells even when the deflection is small.