FULLY IMPLICIT STRESS-UPDATE ALGORITHM FOR EXTENDED SUBLOADING SURFACE MODEL INCORPORATING NONHARDENING STRAIN REGION

• IGUCHI Takuya

  東北大学　大学院工学研究科土木工学専攻

• SATO Taiki

  東北大学　大学院工学研究科土木工学専攻

• LUO Jiahua

  東北大学　大学院工学研究科土木工学専攻

• YAMAKAWA Yuki

  東北大学　大学院工学研究科土木工学専攻

Bibliographic Information

Other Title

• 非硬化ひずみ領域を導入した拡張下負荷面モデルの完全陰的応力計算法の開発

Abstract

In this study, a novel implicit stress-update algorithm of the extended subloading surface model, a class of unconventional plasticity model, incorporating the nonhardening strain region is developed to improve the predictive capability for cyclic loading property of metallic materials. Ohno (1982; J. Appl. Mech., ASME) proposed a sophisticated plasticity model equipped with nonhardening strain region in order to reproduce the stagnation of isotropic hardening resulting in transient stabilization of hysteresis loop during cyclic loading with a fixed strain amplitude. In the plastic strain space, when the plastic strain moves inside the nonhardening strain region, the region does not expand, and hence, isotropic hardening does not proceed,while only kinematic hardening proceeds. When the plastic strain moves outside of the nonhardening strain region, isotropic hardening proceeds being accompanied by expansion of the region. As a specific prototype model, von Mises plasticity model is reformulated based on the hyperelastic constitutive equations within the framework of infinitesimal deformation theory. A numerical algorithm for stress calculation using return mapping is developed, in which we devise a novel scheme consisting of hardening/nonhardening judgment and nested iteration to update variables associated with the nonhardening strain region. Numerical examples of cyclic loading demonstrate that the developed constitutive model properly reproduces the stabilization of hysteresis loop. The iteration solution process exhibits satisfactory convergent property, which validates the numerical scheme developed in this study.

Journal

• Journal of Japan Society of Civil Engineers, Ser. A2 (Applied Mechanics (AM))

  Journal of Japan Society of Civil Engineers, Ser. A2 (Applied Mechanics (AM)) 76 (2), I_193-I_204, 2020

  Japan Society of Civil Engineers

Keywords

• <i>Elasto-plasticity</i>
• <i>Nonhardening strain region</i>
• <i>Return-mapping</i>
• <i>Stabilization of hysteresis loop</i>
• <i>Stagnation of isotropic hardening</i>

Details

• CRID: 1391412881287897216
• NII Article ID: 130007980156
• DOI: 10.2208/jscejam.76.2_i_193
• ISSN: 21854661
• Web Site: https://www.jstage.jst.go.jp/article/jscejam/76/2/76_I_193/_pdf
• Text Lang: ja
• Data Source:
  • JaLC
  • Crossref
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed