Methodological approaches to the implementation of the calculation of shell pipelines beyond the limits of elasticity under cyclic loading

Abstract

This article provides methodological approaches to the implementation of the calculation of shell pipelines
beyond the limits of elasticity under cyclic loading. For this purpose, the formulation of the problem and the
process of deformation of pipeline elements – cylindrical shells beyond the limits of elasticity under repeated
variable loading are formulated. Based on the Hamilton-Ostrogadsky variational principle, equations of
motion are derived for main pipelines – cylindrical shells interacting with the ground under single and cyclic
loads with appropriate boundary and initial conditions beyond the limits of elasticity under cyclic loading.
A procedure for solving a boundary value problem using the finite difference method and “elastic” solutions
has been developed. The stress-strain state of the compensator pipeline under repeated loading is
investigated, taking into account the elastic-plastic properties. For a comparative assessment, an elastic
calculation was performed using the ANSYS software package. The calculation results make it possible to
estimate the stress-strain state of pipeline systems under various types of loads, reduce the computational
process time by 1.3-1.4 times and increase the efficiency of design work by 11-15%.