Azisymmetric Nonlinear Consolidation Analysis for Drainage-Installed Compressible Deposits

배수재가 설치된 압축성 지반의 축대칭 비선형 압밀해석

  • 김윤태 (정회원, 한국과학기술원 토목공학과) ;
  • 이승래 (정회원, 한국과학기술원 토목공학과 부교수, 정회원, 현대건설기술연구소 이사)
  • Published : 1996.02.01

Abstract

In order to accelerate the rate of consolidation settlement and to gain a required shear strength for a given soft clay deposit, the preloading technique combined with a vertical drainage system has been widely applied. In this'study, the theory of axisymmetric consolidation which considers the variation of compressibility and permeability during the conslidation process, has ben developed. A computer program named AXICON for the analysis of axisymmetric nonlinear consolidation is developed by adopting an explicit finite difference method. Smear and well resistance effects are also considered. The AXICON is capable of analyzing the consolidation behavior of multi -layered deposits and simulates time dependent loading sequence. The results of AXICON are validated with analytical solutions of Hansbo and Barron, and compared with insitu settlements and pore pressures measured in a soft clay deposit.

연약지반 처리방법으로 압밀을 촉진시키고, 이로 인한 전단강도를 증진시키기 위하여 선행압밀하중공법과 병행된 배수공법이 널리 사용되어 오고 있다. 본 연구에서는 배수재가 설치된 연약지반의 압밀과정동안에 유발되는 간극비의 감소로 인한 압축성과 투수계수의 변화를 고려할 수 있는 축대칭 비선형 압밀이론을 제안하였다. 제안된 축대칭 비선형 압밀이론을 명백한(explicit) 유한차분법을 적용하여 해석용 프로그램(AXICON)을 개발하였으며 현장지반의 교란효과나 층으로 이루어진 지반을 해석할 수 있도록 보완하였다. 또한 현장지반의 단계적 시공절차를 고려하여 하중을 적용할 수 있도록 하였다. AXICON 해석결과를 기존의 Hansbo와 Barren의 해석적인 해와 비교 검토하였으며 현장지반에서 계측된 침하량과 과잉 간극수압의 자료와 비교하였다.

Keywords

References

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