Nonlinear Higher-Mode Effects in Torsionally Coupled Low-Rise Buildings

Yi-Seop Shin; Hyung-Joon Kim

doi:10.7734/COSEIK.2026.39.4.255

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2026 Vol.39, Issue 4 Preview Page Next Page

Nonlinear Higher-Mode Effects in Torsionally Coupled Low-Rise Buildings 횡-비틀림 저층 구조물의 비선형 거동에 따른 고차모드 효과 변화

31 August 2026. pp. 255-263

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Abstract

Higher-mode effects in low-rise buildings exhibiting coupled lateral-torsional behavior can significantly influence seismic response and should be properly reflected in the seismic design procedure. Conventional criteria for identifying higher-mode-dominated response are generally based on elastic response spectrum analysis, which limits their direct application to inelastic structures. This study investigated the influence of structural nonlinearity on higher-mode effects in torsionally coupled low-rise buildings through nonlinear static and nonlinear time-history analyses. Existing elastic-analysis-based higher-mode indicators were evaluated through a comparison with the higher-mode effects observed in nonlinear response. Higher-mode-effects generally decreased with an increase in structural nonlinearity, whereas some structures considered in this study exhibited nonlinear higher-mode effects greater than those estimated in the elastic state. These findings provide insights into the limitations of directly applying elastic higher-mode indicators to nonlinear torsionally coupled structures and can serve as bases for developing assessment approaches that account for nonlinear response characteristics.

Keywords

low-rise buildings

lateral-torsional effect

higher-mode effect

nonlinear time-history analysis

횡-비틀림 거동하는 저층 구조물에서 발생할 수 있는 고차모드는 구조응답에 유의미한 영향을 미칠 수 있으며, 내진 성능평가 및 보강 계획 수립을 위해 이를 적절하게 평가할 필요가 있다. 기존의 고차모드 지배 여부 판별 방법은 주로 탄성응답스펙트럼해석에 기반하고 있어, 비선형 거동하는 구조물에 그대로 적용하기에는 한계가 있을 수 있다. 본 연구에서는 횡-비틀림 거동하는 저층 구조물을 대상으로 비선형 해석을 수행하여 구조물의 비선형 거동이 고차모드 효과에 미치는 영향을 분석하였다. 또한, 기존 탄성해석 기반 고차모드 판별지표와 비선형 응답에서 나타나는 고차모드 효과를 비교함으로써, 비선형 구조물에 대한 기존 판별지표의 적용성을 검토하였다. 해석 결과, 비선형성이 증가할수록 고차모드 효과는 전반적으로 감소하는 경향을 보였으나, 일부 구조물에서는 탄성상태에서 평가된 고차모드 효과보다 비선형 응답에서의 고차모드 효과가 증가하는 경우도 확인되었다. 본 연구의 결과는 비선형 횡-비틀림 구조물에 대한 기존 고차모드 판별지표의 적용 한계를 이해하고, 비선형 응답 특성을 고려한 평가 방법을 정립하기 위한 기초자료로 활용될 수 있을 것으로 판단된다.

키워드

저층 구조물

횡-비틀림 효과

고차모드 효과

비선형시간이력해석

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Information

Publisher :Computational Structural Engineering Institute of Korea
Publisher(Ko) :한국전산구조공학회
Journal Title :Journal of the Computational Structural Engineering Institute of Korea
Journal Title(Ko) :한국전산구조공학회 논문집
Volume : 39
No :4
Pages :255-263
Received Date : 2026-05-21
Revised Date : 2026-06-11
Accepted Date : 2026-06-12
DOI :https://doi.org/10.7734/COSEIK.2026.39.4.255

Journal of the Computational Structural Engineering Institute of Korea ISSN:1229-3059(Print) 2287-2302(Online) 한국전산구조공학회 논문집

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