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2026 Vol.42, Issue 3 Preview Page
Evaluation of the Elastic Modulus of Micropiles through Field Tension Tests

현장인장시험을 통한 마이크로파일의 탄성계수 평가

Kwang-Young Kim1
,
Yeon-Sung Moon2
,
Kang-Il Lee3*
김 광영1
,
문 연성2
,
이 강일3*
1Member, Ph.D. Student, Dept. of Civil and Environmental Engineering, Daejin Univ.
2Member, Graduate Student, Dept. of Smart Civil and Environmental Engineering, Daejin Univ.
3Member, Prof., Dept. of Smart Civil and Environmental Engineering, Daejin Univ.
1정회원, 대진대학교 토목환경공학과 박사과정
2정회원, 대진대학교 스마트시티건설융합공학과 박사과
3정회원, 대진대학교 스마트건설환경공학과 교수
*Corresponding Author
30 June 2026. pp. 101-112
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Abstract

Micropiles are small-diameter cast-in-place piles composed of a steel bar, grout, and steel casing. Initially developed to support existing structures and control settlement, they are now also widely used to support the foundations of new structures and resist uplift forces. As the use of micropiles has increased, studies have primarily focused on the bearing behavior of micropiles and micropiled rafts. However, investigations into the composite behavior and stiffness of micropiles composed of multiple materials remain limited. Consequently, whether such micropiles exhibit integrated structural behavior in the ground remains controversial. To address this issue, field tension tests were conducted on micropiles installed at nine sites in Korea, and their stiffness was evaluated through a comprehensive analysis of the test results. The results confirmed that the micropiles exhibited integrated behavior and that their stiffness was approximately 1.06–1.69 times greater than the theoretical values calculated by considering the cross-sectional area and elastic modulus of each constituent material independently. Overall, the tensile deformation behavior of composite micropiles demonstrated integrated behavior, and the elastic modulus derived from the field test results was approximately 1.06–1.69 times greater than the theoretical elastic modulus calculated from the cross-sectional area and elastic modulus of the individual constituent materials.

Keywords
Elastic or plastic displacement of pile
Field tension test
Micropile
Micropile stiffness
Micropile stiffness ratio
Tensile displacement of pile

마이크로파일은 강봉과 그라우트 및 케이싱으로 구성된 소구경 현장타설말뚝을 말한다. 이 파일은 개발 당시 기존 구조물의 지지력 보강 또는 침하억제를 위한 목적으로 활용되었으나, 최근에는 신설 구조물기초 하부 지지 또는 상향력에 저항하기 위한 목적으로 활용되고 있다. 마이크로파일의 활용이 증가함에 따라 마이크로파일 또는 마이크로파일-기초에 관한 지지특성에 관한 연구가 주로 수행되었다. 그러나 복합재료로 구성된 마이크로파일의 일체화 거동과 말뚝강성의 평가에 관한 연구는 부족한 실정이다. 본 연구에서는 이와 같은 문제를 해결하기 위해 국내 9 개소 현장에 설치된 마이크로파일을 대상으로 인장시험을 수행하였고, 시험결과를 종합적으로 분석하여 마이크로파일의 강성을 평가하였다. 연구결과, 복합재료로 구성된 마이크로파일의 인장변형 특성은 일체화 거동을 보이며, 현장시험을 고려한 마이크로파일의 탄성계수가 재료별 단면적과 탄성계수를 고려한 마이크로파일의 탄성계수보다 약 1.06~1.69 배 증가됨을 확인하였다.

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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 : 42
  • No :3
  • Pages :101-112
  • Received Date : 2026-05-06
  • Revised Date : 2026-06-02
  • Accepted Date : 2026-06-02
  • DOI :https://doi.org/10.7843/kgs.2026.42.3.101
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