Numerical Predictions of the Load-Displacement Curves of Rock-Socketed Concrete Piles

  • Kwon, Oh-Sung (Department of Civil Eng., Seoul National University) ;
  • Kim, Jeong-Hwan (Institute of Technology, Engineering & Constitution Group, Samsung Corporation) ;
  • Jeon, Kyung-Soo (Geotechnical Research Division, Korea Highway Corporation) ;
  • Kim, Myoung-Mo (Department of Civil Eng., Seoul National University)
  • 발행 : 1999.06.01

초록

암반 근입말뚝의 설계기준은 일반적으로 침하량 기준을 사용하므로 설계단계에서 암반근입말뚝의 하중-변위$(\sigma-\sigma)$ 거동을 잘 이해해야 하나 그 거동의 복잡성으로 인해 하중-변위 거동을 파악하기가 어렵다. 이를 위해 먼저 현장타설 콘크리트 말뚝에 대해 현장재하시험을 실시하여 그 결과로부터 암반 근입말뚝의 하중-변위 거동을 고찰하였고, 상용 프로그램인 ELAC을 이용하여 하중-변위 곡선의 형상에 큰 영향을 주는 입력변수를 변화시켜 가며 말뚝의 하중-변위 관계를 모사하였다. 최종적으로 수치해석 입력데이터와 현장 지반조사결과의 관계를 일반화함으로써 지반공학자가 설계단계에서 적절한 현장데이터를 이용하여 하중-변위 거동을 예측할 수 있도록 하였다.

The settlement limit concept is generally adopted as design criteria of rock-socketed pile foundations, therefore, the load-displacement$(\sigma-\sigma)$ behavior of the rock-socketed piles should be well understood at the design stage, which, however, is hard to achieve due to its complexity. To help this out, field pile load tests are executed on cast-in-situ concrete piles, first, to figure out the $\sigma$-$\delta$ behavior of rock-socketed piles. Next, the $\sigma-\sigma$ relations of the piles are simulated numerically using commercial package program(ELAC) varying a couple of input data which are sensitive in shaping the $\sigma$-$\delta$ curves. Finally, the relation between the best input data for the numerical simulations and the geotechnical field data are cultivated to generalize the numerical simulation procedures, which enables geotechnical engineers to predict the $\sigma$-$\delta$ behavior at the design stage, if appropriate geotechnical field data are provided.

키워드

참고문헌

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