PARAMETRIC INSTABILITY OF DOUBLY CURVED PANELS SUBJECTED TO NON-UNIFORM HARMONIC LOADING

The parametric instability characteristics of doubly curved panels subjected to various in-plane static and periodic compressive edge loadings, including partial and concentrated edge loadings are studied using finite element analysis. The first order shear deformation theory is used to model the doubly curved panels, considering the effects of transverse shear deformation and rotary inertia. The theory used is the extension of dynamic, shear deformable theory according to the Sanderʹs first approximation for doubly curved shells, which can be reduced to Loveʹs and Donnellʹs theories by means of tracers. The effects of static load factor, aspect ratio, radius-to-thickness ratio, shallowness ratio, boundary conditions and the load parameters on the principal instability regions of doubly curved panels are studied in detail using Bolotinʹs method. Quantitative results are presented to show the effects of shell geometry and load parameters on the stability boundaries. Results for plates and cylindrical shells are also presented as special cases and are compared with those available in the literature.