Journal of the Korean Geotechnical Society (한국지반공학회논문집)

Korean Geotechnical Society (한국지반공학회)
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Evaluation of Isolation Mechanism of Teflon or Steel Slag-Type Seismic Foundation Isolation Systems

테프론 또는 제강슬래그를 활용한 기초형 지진격리장치의 면진 메카니즘 평가

  • Son, Su Won (Dept. of Civil and Environmental Engrg., Pusan National Univ.) ;
  • Kang, In-Gu (Dept. of Civil and Environmental Engrg., Pusan National Univ.) ;
  • Pouyan, Bagheri (Dept. of Civil and Environmental Engrg., Pusan National Univ.) ;
  • Kim, Jin Man (Dept. of Civil and Environmental Engrg., Pusan National Univ.)
  • 손수원 (부산대학교 사회환경시스템공학과) ;
  • 강인구 (부산대학교 사회환경시스템공학과) ;
  • 푸얀 벅게리 (부산대학교 사회환경시스템공학과) ;
  • 김진만 (부산대학교 사회환경시스템공학과 토목공학전공)
  • Received : 2017.10.13
  • Accepted : 2017.12.06
  • Published : 2018.01.31
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Abstract

In this study, seismic performance of geotechnical seismic isolation system capable of primary seismic isolation in the ground was evaluated. 1-G shaking table test was used to assess the performance of Teflon or steel slag as geotechnical seismic isolation systems installed beneath superstructure foundation. Response acceleration and response spectra were analyzed considering different input motions. The results were compared with those of fixed foundation structure without seismic isolation system. The steel slag-type seismic isolation system showed significant reduction in acceleration. The teflon-type seismic isolation system did not show significant effects on acceleration reduction in low-to-moderate seismicity condition, but it did show better effects in case of strong seismic condition. As input motion was transferred to the upper mass, the response spectrum of the fixed foundation structure was amplified in the short period range. In contrast, the response spectrum of the structure with seismic isolation using teflon or steel slag amplified in the long period range. It is found that the change of periodicity and the friction characteristics between isolation materials and foundations affected acceleration reduction.

본 연구에서는 지반에서 1차적인 면진작용을 할 수 있는 지반형 지진격리장치의 내진성능을 평가하였다. 테프론과 제강슬래그를 이용하여 지반형 지진격리장치를 조성한 후 그 위에 모형 상부구조물을 설치하고 1-G 진동대 실험을 수행하였다. 다양한 수준의 입력지진파에 대해 응답가속도와 응답스펙트럼을 분석하였으며, 지진격리장치가 없는 고정기초 구조물과 결과를 비교하였다. 연구결과, 제강슬래그형 지진격리장치가 가장 가속도 저감효과가 좋았으며, 테프론형 지진격리장치는, 중 약진 조건에서는 가속도 저감효과가 크게 없고 강진조건에서는 가속도 저감효과가 좋았다. 입력파가 상부질량(Mass)으로 전달되면서, 고정기초 구조물의 응답스펙트럼은 입력지진파에 비해 단주기영역에서 증폭하고, 테프론과 제강슬래그를 이용한 지진격리장치가 있는 구조물의 응답스펙트럼은 입력지진파에 비해 장주기 영역에서 증폭하였다. 이러한 주기특성 변화와 재료간의 마찰특성이 가속도 저감효과에 영향을 준 것으로 판단된다.

Keywords

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