Verification of Similitude Law for 1g Shaking Table Tests through Modeling of Models

모형의 모형화 기법을 이용한 1g 진동대 실험을 위한 상사법칙의 유효성 검증

  • Hwang Jae-Ik (School of Civil, Urban & Geosystem Engrg., Seoul National Univ.) ;
  • Kim Sung-Ryul (Research Institute Seoul National Univ.) ;
  • Jang In-Sung (Coastal and Harbor Engrg., Research Lab. Korea Ocean Research and Development Institute) ;
  • Kim Myoung-Mo (School of Civil, Urban & Geosystem Engrg., Seoul National Univ.)
  • 황재익 (서울대학교 지구환경시스템공학부) ;
  • 김성렬 (서울대학교 공학연구소) ;
  • 장인성 (한국해양연구원 연안항만공학연구본부) ;
  • 김명모 (서울대학교 지구환경시스템공학부)
  • Published : 2004.12.01

Abstract

A series of shaking table model tests were performed to verify the validity of similitude law, which is suggested by lai (1989) to simulate the dynamic behavior of soil-fluid-structure system for is shaking table tests. In the tests, the similitude law suggested by lai was applied to determine the length and the time scaling factors. Also, the steady state concept was used in determining the density of model backfill soil, which is a key factor in simulating the development of excess pore pressure during shaking. The similitude law was verified by checking whether three different sizes of quay walls show the identical behavior or not. The similar responses of acceleration, excess pore pressure and horizontal displacement of walls were obtained far the small and large models. However, the medium model showed larger responses than those of the small and large models because of the resonance between the frequency of input acceleration and the natural frequency of the wall system. In addition, the vertical displacement and rotational angle of the walls became larger with the increase of model size.

지반-유체-구조물 시스템에 대한 1g 진동대 실험을 위한 상사법칙의 유효성을 검증하기 위하여 일련의 모형실험을 수행하였다. 크기가 서로 다른 3가지의 모형에 대한 실험결과 분석에는 lai가 제안한 상사법칙뿐만 아니라 과잉간극수압 발생을 위한 정상상태개념도 적용하여 각 크기의 모형이 예측하는 안벽시스템의 거동을 서로 비교하였다. 그 결과, 가속도와 과잉간극수압, 그리고 변위 응답의 경우, 가장 작은 모형벽체와 가장 큰 모형벽체는 비슷한 값을 예측한 반면, 중간크기의 모형벽체는 공진현상으로 인해 엉뚱하게 큰 값을 예측하였다. 또한 벽체의 수직침하와 회전각은 모형의 크기와 관계없이 모형벽체시스템의 크기가 증가할수록 증가하는 경향을 나타내었다.

Keywords

References

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