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Research Article

Analysis of the Physical and Mechanical Properties of Injected High-Density Polyurethane from Laboratory Experiments and Field Tests

실내실험 및 현장실험을 통한 고밀도 폴리 우레탄 공법의 물리 ‧ 역학적 특성 분석

Junyoung Choi1
,
Daehyeon Kim2*
최 준영1
,
김 대현2*
1Graduated Student, Department of Civil Engineering, Chosun University
2Professor, Department of Civil Engineering, Chosun University
1조선대학교 토목공학과 박사과정
2조선대학교 토목공학과 교수
*Corresponding Author
31 March 2021. pp. 83-101
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Abstract

The high-density polyurethane method uses the instantaneous expansion pressure of injected material to stabilize soft ground, allowing reinforcement, restoration, and construction to be carried out in suboptimal ground conditions. Under normal and, even poor conditions, the method is easily applied because the working time is very short. The method is environmentally friendly and results have excellent durability. The purpose of this study was to verify the physical and mechanical properties of high-density polyurethane in the ground. Initial testing of strength, direct shear, and soil environment stability was followed by testing for permeability in order to address environmental concerns. The results of the experiments showed that the internal friction angle was about twice as high and the adhesion was about 2.5 to 3.5 times higher than for dense and hard clay, and that the permeability factor was significantly lower compared with the existing grouting method, within the range of 1.0 × 10-5.

Keywords
expansion material
foam reaction
uniaxial compression test
direct shear test
permeability test

고밀도 폴리 우레탄 공법은 주입 물질의 순간 팽창압을 이용하여 연약지반의 불안정한 지반의 안정화를 위해 적용되며 내구성이 매우 탁월한 친환경 공법이다. 순간 팽창압에 의해 연약지반 보강 및 복원, 차수공사가 가능하다. 본 주입공법의 경우 작업시간이 매우 짧고 신속하여 열악한 환경에서도 타 공법보다 접급성과 작업성이 매우 탁월하다. 따라서 본 연구에서는 고밀도 폴리 우레탄이 지반 내에서 작용하는 물리 ‧ 역학적 특성을 검증하고자 하였다. 먼저, 주입재료의 강도정수 및 물성값을 확인하기 위하여 일축압축강도시험, 직접전단시험, 토압시험 등을 수행하였고 환경적인 문제에 대한 부분을 확인하고자 투수시험 및 토양환경안정성 시험을 수행하였다. 실험결과, 조밀한 사질토와 단단한 점성토를 대상으로 비교하였을 때, 내부마찰각은 약 2배, 점착력은 약 2.5~3.5배 이상 높은 것으로 확인되었고, 투수계수 또한 1.0 × 10-5의 범위 이내를 만족하며, 기존 그라우팅 공법과 비교하였을 때 현저히 낮은 투수계수를 확인할 수 있었다.

키워드
팽창재
발포반응
일축압축강도시험
직접전단시험
투수시험
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Information
  • Publisher :Korean Society of Engineering Geology
  • Publisher(Ko) :대한지질공학회
  • Journal Title :The Journal of Engineering Geology
  • Journal Title(Ko) :지질공학
  • Volume : 31
  • No :1
  • Pages :83-101
  • Received Date : 2021-02-25
  • Accepted Date : 2021-03-12
  • DOI :https://doi.org/10.9720/kseg.2021.1.083
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