Undrained Behavior of Weathered Granite Soil of Heating-Cooling Repeated Acts Using Temperature Control Triaxial Test

Seung-Min  Shin; Chun-Won  Sin; Chung-Sik  Yoo

doi:10.12814/jkgss.2016.15.3.001

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2016 Vol.15, Issue 3 Next Page

Undrained Behavior of Weathered Granite Soil of Heating-Cooling Repeated Acts Using Temperature Control Triaxial Test 온도변화 삼축압축 실험을 이용한 Heating-Cooling 반복 작용시 화강풍화토의 비배수 거동

30 September 2016. pp. 1-12

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Abstract

In this study, the impact of sand and weathered granite soil is analyzed by changing the internal temperature from 20°C~ 70°C by installing a heating coil inside the triaxial cell. To check the effect on weathered granite soil due to increase of temperature and number of heating‑coiling cycles are analyzed by measuring the temperature by using thermometer installed inside the triaxial cell and due to that deviator stress also occurred during the consolidated undrained test. To analyze the effect of weathered granite soil with change of temperature during undrained testing. The deviator stress and pore pressure is measured. As a result, pore pressure increases and the deviator stress decreases with rise of temperature.

Keywords

Thermally active geotechnical structure

Heating-cooling

Stress-strain-strength behavior

Undrained condition

본 논문에서는 지열 활용시스템을 지반구조물에 적용시 발생하는 주변 지반에 부과되는 다양한 온도 및 온도변화 사이클이 흙의 역학적 특성에 미치는 영향에 대한 내용을 다루었다. 이를 위해 화강풍화토를 대상으로 다양한 온도변화 조건을 구현하고 이에 따른 흙의 입자구조 및 열전도특성 변화 경향을 고찰하였다. 아울러 다양한 OCR(over consolidation ratio)값을 가지는 시료를 제작하여 내부 온도를 20°C~70°C까지 변화시키며 온도상승과 가열-냉각 반복작용 횟수에 따른 흙에 미치는 영향을 분석하고자 온도계로 압축셀 내부 온도를 측정하였으며 비배수 실험을 통해 시료에 작용하는 축차응력 및 간극수압을 측정하여 온도변화가 화강풍화토에 미치는 영향을 분석하였다. 그 결과 온도상승과 가열-냉각 반복 작용으로 인해 간극수압이 증가하며 축차응력 또한 감소하는 것으로 관찰되었다.

References

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Information

Publisher :Korean Geosythetics Society
Publisher(Ko) :한국지반신소재학회
Journal Title :Journal of the Korean Geosynthetics Society
Journal Title(Ko) :한국지반신소재학회 논문집
Volume : 15
No :3
Pages :1-12
Received Date : 2016-01-01
Revised Date : 2016-07-24
Accepted Date : 2016-07-26
DOI :https://doi.org/10.12814/jkgss.2016.15.3.001

Journal of the Korean Geosynthetics Society ISSN:2508-2876(Print) 2287-9528(Online) 한국지반신소재학회 논문집

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