Vereshchaka S. Nonlinear deformation and stability of multi-layer construction's units with defects in structure.

Subject of inquiry - non-linear straining and durability of multi-layer constructional elements with structural defects, the objective - development and substantiation of effective methods of solving the problems of non-linear straining and durability of multi-layer constructional elements with structural defects and their application to actual engineering problems. Research methods: penalty function method, Furrier method, finite-difference method, displacement method, orthogonalization method. Theoretical and practical value of the work is in developed and numerically realized common approach to solving the problems of strength, durability and load-carrying ability of geometrically non-linear Contact problems for calculating multi-layer anisotropic shells and plates taking into account both ideal and non-ideal inter-layer contact. Scientific novelty of obtained results: discrete-structural theory of multi-layer constructional elements has obtained further development, peculiarity of which is calculations of non-ideal contact of inter-layer surfaces of neighboring reinforced layers ( exfoliation, slippage); influence of interlayer structural defects on magnitude of load-carrying ability of a new structure of combined high-pressure vessel is investigated. Developed in the dissertation algorithms, programs and methods of investigation have been implemented in applied scientific and technical developments of new structures and products from composite materials at Public limited company Sumskoy scientific production association, joint-stock company scientific production association GYDROMASH, public limited company SUMYGASMASH and in training of Sumy state university. Fields of application: mechanical engineering, building, scientific research establishments.