Calculation of a closed cylindrical shell made of composite material under external axisymmetric load

The modern approach to structural design involves the use of composite structures, which allow for the desired operational properties to be achieved through the combination of heterogeneous components. Given the widespread application of shell structures made from composite materials in engineering practice, a relevant task is the investigation of their stress-strain state under operational loading conditions. This study examines a closed cylindrical shell composed of an orthotropic material. The objective is to investigate the stress-strain state of the shell when subjected to external pressure loading. An advanced theory is applied that accounts for shear transverse deformations according to S. A. Ambarzumyan. Operational calculus related to Laplace transformation is utilized to solve the governing differential equation. To address the posed problem, the authors derive analytical expressions in general form that can determine the stress-strain state of a cylindrical shell made of orthotropic material for various geometric parameters and elastic characteristics of the material. The external axisymmetric load can be applied at any location along the length of the shell and can act on sections of any size. The article presents various particular solutions derived from general analytical expressions: solutions for the shell under uniform axisymmetric load across its entire surface, under concentrated axisymmetric load along the length of the shell, and under concentrated axisymmetric bending moments along the length of the shell. Test problems are solved in this paper, providing results for calculations of an orthotropic closed cylindrical shell made from carbon fiber composite under external axisymmetric loading.