한국지반공학회논문집 (Journal of the Korean Geotechnical Society)

한국지반공학회 (Korean Geotechnical Society)
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매입말뚝공법의 충전재료로 사용되는 시멘트밀크의 공학적 특성

Engineering Characteristics of Cement Milk for Bored Piles

  • 도종남 (한국도로공사 도로교통연구원 구조물연구실) ;
  • 남문석 (한국도로공사 도로교통연구원 구조물연구실) ;
  • 심재원 (한국도로공사 도로교통연구원 안전연구실) ;
  • 박영호 (한국도로공사 도로교통연구원 안전연구실) ;
  • 이승준 (한국도로공사 도로교통연구원 안전연구실)
  • 투고 : 2015.09.14
  • 심사 : 2015.12.08
  • 발행 : 2015.12.31
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초록

본 연구에서는 매입말뚝공법의 충전재료로 사용하는 시멘트밀크의 공학적 특성 시험을 실시하였다. 이를 위해 고속도로공사 전문시방서에서 사용하고 있는 표준공시체를 기준으로 다양한 물/시멘트 비율로 공시체를 제작하였다. 또한, 재령일에 따른 일축압축강도, 점하중강도, 탄성계수, 그리고 포아송비 시험을 실시하였다. 시험결과 물/시멘트 비의 변화에 따른 시멘트밀크의 표준 공시체 제작을 위한 주입높이를 제시하였다. 재령 7일과 28일에 대한 일축압축강도와 점하중강도와의 비인 시멘트밀크의 상관계수, K는 각각 $K_7=4.55{\sim}13.65$와 $K_{28}=5.28{\sim}16.84$ 이었다. 재령일과 무관하게 물/시멘트 비가 65~150%일 때 탄성계수와 포아송비의 증감은 크게 나타났고, 150~300%는 상대적으로 매우 작게 나타났다. 마지막으로 재령별 물/시멘트 비에 따른 시멘트밀크의 일축압축강도, 점하중강도, 일축압축강도와 점하중강도와의 상관계수, 탄성계수, 포아송비의 식을 제안하였다.

In this study, engineering property tests were conducted for cement milk used as a filling materials in the bored piles method. For this purpose, various water/cement ratio specimens were produced on the basis of standard specimen specified in highway corporation specifications. The unconfined compressive strength, point load strength, elasticity modulus, poisson's ratio test was performed according to the age. As a test result, injection height for productions of cement milk specimens was defined ratios. Correlation coefficient K of the unconfined compressive strength and point load strength were $K_7=4.55{\sim}13.65$ in age 7 days, and $K_{28}=5.28{\sim}16.84$ in age 28 days. When water / cement ratio is 65-150%, the elastic modulus and Poisson's ratio significantly increased and decreased regardless of age. In addition, the formulae were proposed for unconfined compressive strength, point load strength, a correlation coefficient of unconfined compressive strength, point load strength, elastic modulus, and poisson's ratio for each age.

키워드

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피인용 문헌

  1. Study on the Increase of the Supporting Capacity of a Cement Milk Pile with Expansive Additives vol.11, pp.21, 2021, https://doi.org/10.3390/app11219922