Techno Press
You logged in as Techno Press

Steel and Composite Structures
  Volume 42, Number 5, March10 2022 , pages 657-669

Efficient determination of combined hardening parameters for structural steel materials
Sang Whan Han, Jungho Hyun, EunSeon Cho, Kihak Lee

    Structural materials can experience large plastic deformation under extreme cyclic loading that is caused by events like earthquakes. To evaluate the seismic safety of a structure, accurate numerical material models should be used. For a steel structure, the cyclic strain hardening behavior of structural steel should be correctly modeled. In this study, a combined hardening model, consisting of one isotropic hardening model and three nonlinear kinematic hardening models, was used. To determine the values of the combined hardening model parameters efficiently and accurately, the improved opposition-based particle swarm optimization (iOPSO) model was adopted. Low-cycle fatigue tests were conducted for three steel grades commonly used in Korea and their modeling parameters were determined using iOPSO, which was first developed in Korea. To avoid expensive and complex low cycle fatigue (LCF) tests for determining the combined hardening model parameter values for structural steel, empirical equations were proposed for each of the combined hardening model parameters based on the LCF test data of 21 steel grades collected from this study. In these equations, only the properties obtained from the monotonic tensile tests are required as input variables.
Key Words
    combined hardening model; empirical equation; inelastic cyclic; low cycle fatigue test; model parameter; optimization; regression; structural steel
Sang Whan Han:Department of Architectural Engineering, Hanyang University, Seoul 04673, Korea

Jungho Hyun:Department of Architectural Engineering, Hanyang University, Seoul 04673, Korea

EunSeon Cho:Department of Architectural Engineering, Hanyang University, Seoul 04673, Korea

Kihak Lee:Department of Architectural Engineering, Sejong University, Seoul 05006, Korea

Techno-Press: Publishers of international journals and conference proceedings.       Copyright © 2023 Techno Press
P.O. Box 33, Yuseong, Daejeon 305-600 Korea, Tel: +82-42-828-7996, Fax : +82-42-828-7997, Email: