A Model for Refined Calculation of the Stress-Strain State of Sandwich Conical Irregular Shells

Abstract

Based on layer-by-layer analysis, we consider the construction of a model of two types of finite elements (FE) with natural curvature: a two-dimensional FE model of the moment of load-bearing layers and the three-dimensional FE of a filler for a more refined study of the stress-strain state (SSS) in the layers using the example of three-layer conical, generally irregular shells. The algorithm for constructing the model can avoid the errors caused by a discontinuity in the generalized displacements on the docking surfaces of the FEs of the bearing layers and filler. The model can more adequately to take into account the features of layered-heterogeneous structure (for example, a continuity violation of one or more layers), the moment state of bearing layers, the three-dimensional SSS in the filler, as well as different conditions for fixing and loading layers. In this case, it is possible to calculate the sandwich shells with variable geometric and physicomechanical properties and take into account the change in these properties and parameters of the SSS not only by meridional and circumferential coordinates, but also by the thickness of the shell and filler layer. As an example, the problem of determining the SSS parameters of a sandwich conical shell with blind cutouts in the inner bearing layer is solved, while the outer bearing layer and the filler layer remain continuous.