불포화 벤토나이트 완충재의 수분흡입력 측정기술 및 구성모델 고찰

• 영문명: A Review on Measurement Techniques and Constitutive Models of Suction in Unsaturated Bentonite Buffer
• 발행기관: 한국방사성폐기물학회
• 저자명: 이재완 윤석 김건영
• 간행물 정보: 『Journal of Nuclear Fuel Cycle and Waste Technology (JNFCWT)』Vol.17 No.3, 329~338쪽, 전체 10쪽
• 주제분류: 공학 > 공학일반
• 파일형태: PDF
• 발행일자: 2019.09.30

국문 초록

Suction of unsaturated bentonite buffers is a very important input parameter for hydro-mechanical performance assessment and design of an engineered barrier system. This study analyzed suction measurement techniques and constitutive models of unsaturated porous media reported in the literature, and suggested suction measurement techniques and constitutive models suitable for bentonite buffer in an HLW repository. The literature review showed the suction of bentonite buffer to be much higher than that of soil, as measured by total suction including matric suction and osmotic suction. The measurement methods (RH-Cell, RH-Cell/Sensor) using a relative humidity sensor were suitable for suction measurement of the bentonite buffer; the RH-Cell /Sensor method was more preferred in consideration of the temperature change due to radioactive decay heat and measurement time. Various water retention models of bentonite buffers have been proposed through experiments, but the van Genuchten model is mainly used as a constitutive model of hydro-mechanical performance assessment of unsaturated buffers. The water characteristic curve of bentonite buffers showed different tendencies according to bentonite type, dry density, temperature, salinity, sample state and hysteresis. Selection of water retention models and determination of model input parameters should consider the effects of these controlling factors so as to improve overall reliability.

키워드

Suction Water characteristic curve Water retention model Unsaturated bentonite Buffer High-level waste repository