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2015 Vol.31, Issue 2 Preview Page
Bearing Characteristics of Micropile-raft by Failure Mode of Soil

지반파괴거동에 따른 마이크로파일-기초의 지지특성

Tae-Hyun Hwang1
,
Jong-Ho Shin2
,
In-Goo Huh3
,
Oh-Yeob Kwon4*
황 태현1
,
신 종호2
,
허 인구3
,
권 오엽4*
1Adjunct Prof., Ph-D., Dept. of Civil Engrg., Konkuk Univ.
2Prof., Ph-D., Dept. of Civil Engrg., Konkuk Univ.
3President, Ph-D., Geotechnial & Structure Construction Co., Ltd.
4Prof., Ph-D., Dept. of Civil Engrg., Konkuk Univ.
1건국대학교 공과대학 토목공학과 겸임교수
2건국대학교 공과대학 토목공학과 교수
3지앤에스건설(주) 대표이사
4건국대학교 공과대학 토목공학과 교수
*교신저자. *Corresponding Author. 
28 February 2015. pp. 13-25
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Abstract

With the increasing usages of micropile, several researchers have been studying the bearing characteristics of micropile or micropile-raft system. But most cases of research were focused on the bearing capacity of micropile-raft system on sand layer. And it was not considered that the bearing capacity of micropile-raft system was affected by the failure mode of soil and pile installation conditions. Thereby this study conducted the numerical analysis to estimate the bearing capacity of micropile-raft system on sand or silt layer with different shear failure mode. It was found that the bearing capacity of micropile-raft system installed in positive or negative angle was larger than that of the system installed in vertical angle, in the case of the sand layer undergoing the general shear failure. In the case of silt layer undergoing the punching shear failure, the bearing capacity of micropile-raft system installed only in negative angle was larger than that installed in vertical or positive angle. And the bearing capacity of foundation system in positive angle was similar to the vertical micropile-raft system.

Keywords
Micropile-raft
Failure mode of soil
Length ratio of pile
Installation angle of pile
Numerical Analysis

최근 마이크로 파일의 활용 빈도가 점차 증가함에 따라 몇몇 연구자들은 마이크로파일 및 마이크로파일-기초에 대한 관련 연구를 수행하였다. 그러나 대부분의 관련연구는 모래지반을 대상으로 한 경우이다. 또한 마이크로파일-기초시스템의 지지특성은 기초시스템내 하부지반의 파괴거동과 파일설치조건에 따라 기초시스템의 지지력이 달라지나 이를 고려하지 않고 있다. 따라서 본 연구에서는 파괴거동이 상이한 지반에 설치된 마이크로파일-기초시스템의 지지력을 평가위해 수치해석을 수행하였다. 해석결과, 전면전단파괴가 발생한 모래지반에서는 기초시스템의 파일을 양 또는 음의 각도로 설치한 경우가 수직파일로 설치된 기초시스템보다 큰 것으로 나타났다. 관입파괴형상으로 파괴가 발생한 실트지반의 경우, 파일이 교차하도록 음의 각도로 설치한 기초시스템이 수직파일인 경우보다 지지력이 증가하였다. 그리고 양의 각도로 설치한 경우에는 수직인 경우와 유사한 것으로 나타났다.

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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 : 31
  • No :2
  • Pages :13-25
  • Received Date : 2014-04-24
  • Revised Date : 2014-10-01
  • Accepted Date : 2014-11-12
  • DOI :https://doi.org/10.7843/kgs.2015.31.2.13
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