Shear Strength-strain Behavior of Unsaturated Weathered Soil (SM)

Sang-Seom Jeong; Seong-Cheol Lee; Seung-Hwa Jeong

doi:10.7843/kgs.2022.38.2.5

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2022 Vol.38, Issue 2 Next Page

Research Article

Shear Strength-strain Behavior of Unsaturated Weathered Soil (SM) 화강풍화토(SM soil)의 불포화 전단거동 분석

28 February 2022. pp. 5-13

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Abstract

The unsaturated behavior of sandy silt (SM soil) was investigated experimentally. Special attention was given to the stress-strain behavior of unsaturated weathered soil (SM) prior to failure and behavior at failure under monotonic loading. A sandy silt (SM) weathered soil containing a certain amount of fine contents distributed in Korea, was chosen to form samples with different densities of Dr=25%, 60%, and 75%. and matric suctions. The isotopically Consolidated Drain test (CD-test) was performed to maintain a constant matric suction during the shearing process. Based on the experimental results, it was qualitatively identified that the higher the relative density, the greater the virtual friction angle (ϕ^b) value and AEV (Air Entry Value) were induced. Also it is found that the internal friction angle (ϕ^′) is more or less constant. even if the matric suction is increased.

Keywords

Apparent cohesion

Consolidation Drain test (CD-test)

Matric suction

Relative density

Unsaturated triaxial loading test

Unsaturated shear strength

Virtual friction angle

Weathered soil

불포화토의 전단 특성 평가는 사면, 제방, 댐 등의 안정성과 투수 특성 평가에 매우 중요한 요소이다. 본 연구에서는 화강풍화토의 불포화 전단특성을 파악하기 위하여 불포화 삼축실험을 수행하였다. 실험에 사용된 시료는 국내에 분포하는 세립분이 다량함유된 SM계열 화강 풍화토이며, 다짐을 통하여 재성형 하였다. 모관 흡수력 및 시료의 밀도에 따른 불포화 전단 특성을 분석하였으며, 전단 과정에서 일정한 모관 흡수력을 유지 하기 위해 압밀-배수삼축실험(CD-test)을 수행하였다. 본 연구결과 화강풍화토 시료의 겉보기마찰각(ϕ^b)과 AEV(Air Entry Value)는 상대밀도가 증가함에 따라 증가하는 경향을 나타내었다. 그러나 모관흡수력이 증가함에 따라서는 점착력(c) 역시 증가하였지만 내부마찰각(ϕ^′)은 크게 변함이 없는 것으로 확인 되었다.

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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 : 38
No :2
Pages :5-13
Received Date : 2021-09-28
Revised Date : 2022-01-20
Accepted Date : 2022-01-21
DOI :https://doi.org/10.7843/kgs.2022.38.2.5

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

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