This study investigates the effects of structural filtering on floor motions and floor response spectra (FRS) used in the seismic design of nonstructural components. While seismic design guidelines for buildings are well-established, nonstructural components often experience disproportionate damage due to amplified floor motions rather than direct ground shaking. To analyze this phenomenon, linear elastic time-history analyses were conducted on two types of school buildings: a regular single-story building and an irregular four-story building, both with rooftop structures. The study compares the frequency characteristics of ground and floor motions using Fourier Amplitude Spectra (FAS). The results show that buildings act as resonant filters, selectively amplifying harmonic components that are close to their natural frequencies. Additionally, the study evaluates the FRS by comparing numerical results with the displacement response factor and the ASCE 7-16 dynamic amplification factor (DAF). It was found that floor motions converge towards harmonic oscillations predominantly influenced by the building’s fundamental period, resulting in significant peak responses in the FRS. These findings suggest that the current design codes may require refinement to better account for these filtering effects, particularly for nonstructural components and structures that are sensitive to resonance.

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1. 서 론
2. 구조적 필터링
    2.1 푸리에 진폭 스펙트럼(FAS)
    2.2 전달율 
3. 층운동 주파수 분석
    3.1 해석모델 및 지진파
    3.2 지반운동 및 층운동 주파수 비교
4. 층응답스펙트럼
5. 결 론
/ 감사의 글 /
/ REFERENCES /

• 엄태성(단국대학교 건축학부 교수) | Eom Tae Sung (Professor, School of Architecture, Dankook University) Corresponding author
• 양병준(단국대학교 건축학부 석사과정) | Yang Byeong Jun (Master’s Student, School of Architecture, Dankook University)
• 전민준(단국대학교 내진리모델링연구소 전임연구원) | Jeon Min Jun (Research Associate, Seismic & Remodeling Research Center, Dankook University)
• 김동연(한국교육시설안전원 과장) | Kim Dong Yeon (Manager, Korea Institute of Educational Facility Safety (KOIES))