ELASTIC STABILITY OF THIN ANNULAR PLATES MADE OF RECTILINEARLY ORTHOTROPIC MATERIAL

The paper deals with the elastic stability problem of thin annular pla tes made of moderately orthotropic material. Examples of this kind can be plates with periodically cut, parallel grooves, the areas in-betwe en acting as very low ribs. The numerical solutions are obtained on th e basis of the energy method. The chosen displacement functions can be used to solve the cases of nonaxisymmetric buckling of the ring in a circular direction for an axisymmetric radial compressive load acting along the edges. The ultimate buckling forces are calculated for the f ollowing combinations of boundary conditions: both ring edges are rigi dly fixed, the outer edge is rigidly fixed and the inner simply suppor ted and both edges are simply supported. The results analysis has show n that the load carrying capacity depends on the grade of orthotropy w hich effects a change in the rigidity of the ring.