Loss of Stability of Multilayer Cylindrical Shells Formed from Nanocomposite Layers in Various Environments under Lateral Pressure

Multilayer cylindrical shell structures formed with functionally graded nanocomposite (FG-NC) plies have an increasing importance in engineering applications, going beyond traditional composite structures thanks to their advanced mechanical properties, lightness and high temperature resistance. The stability against lateral pressure plays a critical role in terms of the safety and long-term performance of such structures. In this study, the loss of stability of multilayer cylindrical shells formed from FG-NC plies on elastic foundation and in thermal environment under lateral pressure is investigated based on Donnell type shell theory. The determination of effective material properties and thermal expansion coefficients of each layer forming by nanocomposite is based on the method of extended mixture rule and molecular dynamics simulation techniques. The governing partial differential equations derived for cylindrical shells formed from FG-NC plies on two-parameter elastic foundation and assuming the effect of thermal environment are solved by Galerkin procedure and analytical expression is found for critical lateral pressure. In this study, the stability of laminated cylindrical shells composed of NC plies subjected to lateral pressure is investigated by incorporating, for the first time, the combined effects of an elastic foundation and thermal environments. The analyses performed in this study provide theoretical and numerical contributions to existing models in the literature by revealing the behavior of FG-NC cylindrical shells under different temperature conditions and elastic ground effects in detail.