Journal of the Earthquake Engineering Society of Korea (한국지진공학회논문집)

Earthquake Engineering Society of Korea (한국지진공학회)
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An Iterative Scheme for Resolving Unbalanced Forces Between Nonlinear Flexural Bending and Shear Springs in Lumped Plasticity Model

비선형 휨 및 전단 힌지 사이의 불평형력 해소를 위한 수렴계산 기법

  • Kim, Yousok (School of Architectural Engineering, Hongik University)
  • 김유석 (홍익대학교 건축공학부)
  • Received : 2022.09.27
  • Accepted : 2022.10.12
  • Published : 2022.11.01
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Abstract

For a member model in nonlinear structural analysis, a lumped plastic model that idealizes its flexural bending, shear, and axial behaviors by springs with the nonlinear hysteretic model is widely adopted because of its simplicity and transparency compared to the other rigorous finite element methods. On the other hand, a challenging task in its numerical solution is to satisfy the equilibrium condition between nonlinear flexural bending and shear springs connected in series. Since the local forces between flexural and shear springs are not balanced when one or both springs experience stiffness changes (e.g., cracking, yielding, and unloading), the additional unbalanced force due to overshooting or undershooting each spring force is also generated. This paper introduces an iterative scheme for numerical solutions satisfying the equilibrium conditions between flexural bending and shear springs. The effect of equilibrium iteration on analysis results is shown by comparing the results obtained from the proposed method to those from the conventional scheme, where the equilibrium condition is not perfectly satisfied.

Keywords

Acknowledgement

본 연구는 산업통상자원부(MOTIE)와 한국에너지기술평가원(KETEP)의 지원을 받아 수행한 연구과제입니다.(No. 20181510102380)

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