Variations of Lateral Bearing Capacity of 2-row Micropile with Installation Conditions by Model Test

Tae-Hyun Hwang; Mu-Yeun Kim; Yeong-Saeng Lee

doi:10.7843/kgs.2020.36.11.35

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2020 Vol.36, Issue 11 Preview Page Next Page

Research Article

Variations of Lateral Bearing Capacity of 2-row Micropile with Installation Conditions by Model Test 모형시험을 통한 복열 마이크로파일의 설치조건에 따른 수평 지지력 변화

30 November 2020. pp. 35-49

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Abstract

The lateral bearing capacity of the micropile depends on the installed conditions such as number, installation angle and spacing of the pile. Existing research on micropile has been limited to the evaluation of vertical bearing characteristics and suggestion of effective installation methods, and there are few studies on failure mechanisms such as failure mode. And most of the studies on the lateral bearing capacity of micropile are also on the 1-row micropile. Therefore, in this study, a model test was performed to evaluate the behavior and lateral bearing characteristics of a 2-row micropile when the installed conditions such as the installation length, angle, and spacing of the pile were different. As a result of the model test, when the installation angle is θ > 0° (Not cross installation), the lateral bearing capacity of 2-row micropile depends on the spacing of the piles, and the installation angle θ = +30° was the most effective for increasing the bearing capacity. In addition, when the installation angle is θ < 0° (Overlap installation), it depends on the spacing and angle of the pile, and the condition of installation angle =-15° was found to be the most effective for increasing the bearing capacity.

Keywords

Installed conditions of micropile

Interaction effect of pile

Micropile

Model test

마이크로파일의 수평 지지력은 파일의 본 수, 설치 각도와 간격 등 설치조건에 좌우된다. 마이크로파일에 관한 기존 연구는 연직 지지특성에 대한 평가와 효과적인 설치방법의 제안 등에 국한되어 있고, 파괴 모드와 같은 파괴 메커니즘 등에 대한 연구는 거의 없는 실정이다. 또한 대부분의 수평 지지력에 관한 연구도 단열 마이크로파일(1-row micropile)에 관한 것이다. 이에 본 연구에서는 파일의 설치 길이, 각도, 간격 등 설치조건을 달리한 경우 복열 마이크로파일(2-row micropile)의 거동 및 지지특성을 평가하기 위하여 모형시험을 수행하였다. 모형시험결과, 설치 각도 θ > 0°인 경우(비교차 설치)의 복열 마이크로파일의 수평 지지력은 파일의 간격에 좌우되며, 설치 각도 θ = +30°인 조건이 지지력 증대에 가장 효과적이었다. 또한 설치 각도 θ < 0°인 경우(교차 설치)에는 파일의 간격과 각도에 좌우되며, 설치 각도 θ = -15°인 조건이 지지력 증대에 가장 효과적인 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 : 36
No :11
Pages :35-49
Received Date : 2020-08-19
Revised Date : 2020-10-28
Accepted Date : 2020-10-28
DOI :https://doi.org/10.7843/kgs.2020.36.11.35

Journal of the Korean Geotechnical Society ISSN:1229-2427(Print) 2288-646X(Online) 한국지반공학회 논문집

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