A Study on the Strength Evaluation of Micropile with Expanded Drill Hole

확공형 마이크로 파일의 강도 평가에 관한 연구

  • Lee, Jae-Min (SAMHO Soil Tech Co., LTD.) ;
  • Kim, Doo-Hwan (Department of Civil Engineering, Seoul National University of Science and Technology)
  • 이재민 (삼호쏘일텍(주)) ;
  • 김두환 (서울과학기술대학교 건설시스템디자인공학과)
  • Received : 2014.05.23
  • Accepted : 2014.10.13
  • Published : 2014.10.31


This study proposes an advanced type of a micropile system. The proposed micropile system consists of perfobond ribs installed steel rod to improve shear capacity between the thread and the grout, and partially expanded drill holes to increase resistance capacity between the grout and the ground. This study contains experimental evaluations on the proposed micropile system to verify the shear capacity of perfobond rib installed on the steel rod and the load-carrying capacity of shear key created by the partially expanded drill hole. Push-out tests were conducted on a rolled screw thread and steel rods which perfobond ribs are installed instead of rolled screw, in order to compare their load-carrying capacity and behavioral characteristics. As a result, it was confirmed that the perfobond-rib steel rods show much superior structural behavior in terms of initial stiffness, ultimate load, and ductile behavior.


Supported by : 서울과학기술대학교


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