A MODIFIED SHAKEDOWN ANALYSIS FOR KINEMATIC HARDENING PIPING UNDER THERMAL-MECHANICAL LOAD

Abstract

Shakedown analysis is a powerful tool for the ratchet ＆ alternating plasticity prediction of the pressure piping under thermal-mechanical loads. In order to achieve the shakedown analysis containing the synergetic influence of the kinematic hardening and the temperature-dependent properties of the material,a numerical method was developed. The presenting method is an extension of the two-surface model for shakedown analysis and is based on the basis reduction method. The idea is to transfer the nonlinear programming resulting from the shakedown analysis with kinematic hardening and temperature-dependent nature into an elastic perfectly plastic one which can be solved with less effort. Numerical examples indicated that the proposed method is accurate. This method has the potential to improve the accuracy of failure prediction for the piping suffering thermal-mechanical loads and therefore is of engineering values.

Keywords

• Ratchet
• Shakedown
• Temperature-dependent properties
• Kinematic hardening
• Piping