Analysis of creep deformation and creep damage in thin-walled branched shells from materials with different behavior in tension and compression

Abstract

A constitutive model for describing the creep and creep damage in initially isotropic materials with different properties in tension and compression has been applied to the modeling of creep deformation and creep damage growth in thinwalled shells of revolution with the branched meridian. The approach of establishing the basic equations for axisymmetrically loaded branched shells under creep deformation and creep damage conditions has been introduced. To solve the initial/boundary-value problem, the fourth-order Runge-Kutta-Merson's method of time integration with the combination of the numerically stable Godunov's method of discrete orthogonalization is used. The solution of the boundary value problem for the branched shell at each time instant is reduced to integration of the series of systems of ordinary differential equations describing the deformation of each branch and the shell with basic meridian. Some numerical examples are considered, and the processes of creep deformation and creep damage growth in a shell with non-branched meridian as well as in a branched shell are analyzed. The influence of the tension-compression asymmetry on the stress-strain state and damage evolution in a shell with non-branched meridian as well as in a branched shell with time are discussed.

Numerical modeling of creep and creep damage in thin plates of arbitrary shape from materials with different behavior in tension and compression under plane stress conditions

“…The realistic behavior of initially isotropic materials under discussion is similar to the creep deformation and creep damage development in an aluminum alloy AK4-1T at the temperature of 200 • C, which has been discussed by many authors [6,8,10,20,23,[27][28][29][30][31][32][33][34][35][36][37].…”

“…It is possible to rewrite Equation (37) in the following generalized form, at the fixed instant of time:…”

“…For the first time, the one-dimensional boundary value problem of bending of thin circular plates and thin shells, taking into account the actual tension/compression creep asymmetry, was considered by Zolochevsky [73], and subsequently by Betten and Borrmann [74]. Following this, the effect of the kind of the stress state on the bending under creep and creep damage conditions for thin shells composed of the initially isotropic materials with three independent characteristics of creep and creep damage has been discussed by Zolochevsky [34], Altenbach and Zolochevsky [28], and Zolochevsky et al [37]. However, to the best of the authors' knowledge, till date, no numerical investigations of the effect of the kind of the stress state on the tertiary creep process and creep damage evolution in two-dimensional boundary value problems, with consideration of the materials exhibiting different behaviors in different loading scenarios, such as tension, compression and shear, exist.…”

Influence of the Stress Mode on the Strength of High-Pressure Vessels

“…The strength of high-pressure vessels depends on many factors, including geometry, material properties, loading conditions, etc. The material properties are known to strongly depend on the stress mode in some cases, which is manifested, for example, as a difference between the tensile and compressive stress-strain curves [20][21][22].Here we will assess the effect of the stress mode on the critical load for a specific thin-walled member of a critical structure. To this end, we will solve, step by step, the axisymmetric problem of plasticity for a thin isotropic shell modeling the structural member under consideration, with and without regard to the stress mode.…”

“…The strength of high-pressure vessels depends on many factors, including geometry, material properties, loading conditions, etc. The material properties are known to strongly depend on the stress mode in some cases, which is manifested, for example, as a difference between the tensile and compressive stress-strain curves [20][21][22].…”