Journal of the Korean Geotechnical Society (한국지반공학회논문집)

Korean Geotechnical Society (한국지반공학회)
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Estimation of Ultimate Bearing Capacity of SCP and GCP Reinforced Clay for Laboratory Load Test Data

SCP 및 GCP 개량 점성토지반의 실내재하시험에 대한 극한지지력 산정 방법 개발

  • Bong, Tae-Ho (School of Civil and Construction Engrg., Oregon State Univ.) ;
  • Kim, Byoung-Il (School of Civil and Construction Engrg., Oregon State Univ.) ;
  • Han, Jin-Tae (Earthquake Safety Research Center, Korea Institute of Civil Engrg. & Building Technology)
  • 봉태호 (오레곤 주립대학교 토목건설공학과) ;
  • 김병일 (오레곤 주립대학교 토목건설공학과) ;
  • 한진태 (한국건설기술연구원 지진안전연구센터)
  • Received : 2018.04.19
  • Accepted : 2018.05.31
  • Published : 2018.06.30
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Abstract

In this study, 34 laboratory load test data were collected, and analyzed to propose the equations for predicting ultimate bearing capacity of sand compaction pile (SCP) and gravel compaction pile (GCP) reinforced clay. The collected data were compared with the ultimate bearing capacity estimated by existing theoretical equations, and the prediction accuracy of the existing theoretical equations was identified. Also, multiple regression analysis was performed to predict the ultimate bearing capacity, and the most efficient number and type of input variables were selected through error evaluation by leave-one-out cross validation. Finally, the multiple regression equations for estimating the ultimate bearing capacity of laboratory load test for SCP and GCP were proposed, and their performance was evaluated.

본 연구에서는 모래다짐말뚝(sand compaction pile, SCP)과 자갈다짐말뚝(gravel compaction pile, GCP)으로 보강된 지반의 극한지지력을 예측할 수 있는 식을 제안하고자 34개의 국내외 실내재하시험 데이터를 수집하고 이를 분석하였다. 수집된 자료를 기존의 이론식에 의한 극한지지력 산정 값과 비교하여 기존 이론식의 예측 정도를 파악하였다. 또한 극한 지지력 예측식을 제안하고자 다중회귀분석을 수행하였으며, 단일잔류 교차검증에 따른 예측오차평가를 통하여 가장 효율적인 입력변수의 수 및 조합을 선정하였다. 최종적으로 SCP와 GCP의 실내재하시험에 대한 극한 지지력을 예측하기 위한 다중회귀식을 제안하였으며 그 성능을 평가하였다.

Keywords

References

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