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1g 진동대 실험을 이용한 연약 점성토 지반에서의 동적 p-y 곡선 연구

A Study on the Dynamic p-y Curves in Soft Clay by 1 g Shaking Table Tests

  • 한진태 (서울대학교 건설환경공학부) ;
  • 유민택 (서울대학교 건설환경공학부) ;
  • 최정인 (서울대학교 건설환경공학부) ;
  • 김명모 (서울대학교 건설환경공학부)
  • Han, Jin-Tae (Dept. of Civil & Environmental Engrg., Seoul National Univ.) ;
  • Yoo, Min-Taek (Dept. of Civil & Environmental Engrg., Seoul National Univ.) ;
  • Choi, Jung-In (Dept. of Civil & Environmental Engrg., Seoul National Univ.) ;
  • Kim, Myoung-Mo (Dept. of Civil & Environmental Engrg., Seoul National Univ.)
  • 투고 : 2010.06.18
  • 심사 : 2010.07.20
  • 발행 : 2010.08.31

초록

본 연구에서는 연약 점성토 지반에 근입된 모형말뚝을 대상으로 다양한 입력 가속도 크기 및 진동수 조건에서 1g 진동대 실험을 수행하였다. 실험 결과를 이용하여, 각각의 동적 p-y 곡선을 산정하였으며, 이 p-y 곡선 상에서 최대지반반력이 나타나는 꼭지점들을 연결하여 연약 점성토의 동적 p-y 중추곡선(Backbone curve)을 쌍곡선 함수로 나타내었다. 이 쌍곡선 함수를 정의하는데 필요한 초기 기울기와 극한 저항력은 Matlock의 p-y 곡선 공식을 이용하여 제안하였다. 새로 제안한 동적 p-y 중추곡선은 실제 내진설계에 사용되고 있는 정적 p-y 곡선과 다른 연구자들의 원심모형실험 결과 및 수치해석 결과와 비교하여 검증하였다.

In this study, a series of 1 g shaking table tests were carried out for a single pile in soft clay with various input acceleration amplitudes and frequencies. Based on the results, dynamic p-y curves were drawn and, in turn, the dynamic p-y backbone curve was formed by connecting the peak points, corresponding to the maximum soil resistance, of the dynamic p-y curves. In order to represent the p-y backbone curve numerically, Matlock's p-y formulations for clay was used to find the initial stiffness ($k_{ini}$) and the ultimate capacity ($p_u$) of the clay, both of which are required to formulate the p-y backbone curve as a hyperbolic function. The suggested p-y backbone curve was verified through comparisons with currently available p-y curves as well as other researchers' centrifuge test results and numerical analysis results.

키워드

참고문헌

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