Effect of Imperfection on Ponding Instability

Abstract

The theory of ponding instability of inflated imperfect spherical membranes subjected to a central load is considered. The equilibrium of the imperfect spherical cap is analyzed and the expression relating the critical central weight to the imperfection geometry and the properties of the membrane for the onset of collapse is derived. Some comparisons of the present results with experimental data (12,13) are carried out and it is concluded that imperfections in the test models (12,13) were responsible for the discrepancies between theoretical predictions and the experimental findings.