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2017 Vol.33, Issue 3 Preview Page
Evaluation of Spudcan Penetration/Extraction Behavior in Uniform Sand and Clay

모래와 점토 단일지반에서의 스퍼드캔 관입/추출 거동 평가

Jin-Kwon Yoo1
,
Duhee Park2*
,
Jaemo Kang3
유 진권1
,
박 두희2*
,
문 재모3
1Graduate Student, Dept. of Civil and Environmental Engrg., Hanyang Univ.
2Associate Prof., Dept. of Civil and Environmental Engrg., Hanyang Univ.
3Graduate Student, Dept. of Civil and Environmental Engrg., Hanyang Univ.
1한양대학교 건설환경공학과 박사과정
2한양대학교 건설환경공학과 부교수
3한양대학교 건설환경공학과 박사과정
*교신저자. *Corresponding Author. 
31 March 2017. pp. 17-28
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Abstract

We performed laboratory spudcan penetration and extraction tests considering various geometries. Jumunjin sand, representative standard sand in South Korea, and kaolinite were used for uniform sand and clay layers, respectively. The measured vertical bearing and pull-out capacities were compared to empirical equations for shallow foundations. The results showed good agreement between measured and calculated bearing capacity from laboratory test and previous study at shallow depths. The effect of spudcan geometry is shown to depend on site condition. The influence of a sharp spigot is not significant in clays. The slope of the spudcan surface is shown to influence the pull-out capacity. The characteristics of spudcan penetration and extraction behavior considering various geometries can be a useful reference for determining spudcan geometries.

Keywords
Spudcan
Penetration/extraction test
Spudcan geometry
Bearing capacity

본 연구에서는 다양한 형상 및 서로 다른 스케일로 설계된 스퍼드캔을 통한 관입/추출 실내 시험을 수행하였다. 이를 위해 국내의 대표적인 표준사인 주문진 모래와 카올리나이트를 사용하여 모래지반과 점토지반을 각각 조성하였다. 관입 시험을 통해 측정된 지지력은 기존 연구자들에 의해 제시된 얕은 기초 지지력 경험식으로 계산된 지지력과 비교하였으며, 스퍼드캔의 형상에 따른 관입/추출 시의 지지력 및 추출 시 요구되는 추출력의 차이를 비교･분석하였다. 분석 결과, 기존 연구자들에 의해 제시된 지지력 산정 경험식은 실제 관입을 통해 측정되는 지지력을 얕은 심도에서 비교적 정확하게 예측할 수 있는 것으로 나타났다. 형상에 따른 차이는 모래지반과 점토지반에서 각각 다르게 나타났으며 상대적으로 연약한 점토지반에서 날카로운 spigot으로 인한 영향이 적은 것으로 나타났다. 또한 스퍼드캔의 경사는 관입 시 보다는 추출 시 요구되는 추출력에 더 큰 영향을 주는 것으로 나타났다. 본 연구를 통해 나타난 모래와 점토지반에서의 스퍼드캔 형상 별 관입/추출 거동 특성을 통해 스퍼드캔 설계 시 형상에 따른 지지력 및 추출력 특성파악에 참고자료가 될 수 있을 것으로 판단된다.

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Information
  • Publisher :The Korean Geotechnical Society
  • Publisher(Ko) :한국지반공학회
  • Journal Title :Journal of the Korean Geotechnical Society
  • Journal Title(Ko) :한국지반공학회 논문집
  • Volume : 33
  • No :3
  • Pages :17-28
  • Received Date : 2016-07-06
  • Accepted Date : 2017-03-22
  • DOI :https://doi.org/10.7843/kgs.2017.33.3.17
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