Lyubitska K. The stress-strain state of flexible orthotropic plates and shallow shells with complex plan form

The object of research is geometrically-nonlinear bending of orthotropic plates and shallow shells of complex geometry, located on elastic foundation under action of axial and transverce loading. The goal of this study is development of numerical-analytical method of a strength calculation of thing-wall design elements, which are simulated by orthotropic plates and flat shells, taking in acount geometrical non-linearity elastic foundation and combined loading. Methods of research: Ritz's Variational method, R-function theory, methods of step-by-step loading and Newton-Kantorovitch's , method of consecutive approximations. The algorithm was derived to find the top and the bottom critical loads, as well as the algorithm of "Load vs Bending" deformation curve. The scientific novelty is in use of R-function method to create a numerical-analytical method of solving geometrically-nonlinear bending problems of flexible orthotropic plates and shallow shells of complex shapes, which interact with elastic foundation and are subjected to combined load of transverce load and in-plane loads. Methodology and results are being used by PAT "NKMZ" and in research/educational process of NTU "KhPI"