Published Online: 18 July 2013
Page Count: 12
Senior Researcher, Geotechnical Engineering Research Division, Korea Institute of Construction Technology, Goyang-Si, Gyeonggi-Do
Professor, Dept. of Civil, Environmental and Architectural Engineering, Univ. of Colorado at Boulder, UCB 428, Boulder, CO
(Received 26 February 2012; accepted 27 May 2013)
Characterization of the suction response and the soil–water retention curve (SWRC) is important for geotechnical engineering applications and is a factor linking unsaturated soil mechanics with geotechnical practice. Therefore, a reliable and convenient method is needed to obtain parameters for models describing flow phenomena in unsaturated soils. Many SWRC measurement methods, including those using flow pump systems, have been developed. This paper describes the operation and limitations of an improved automated flow pump system for accurate SWRC measurement over drying and wetting cycles. We measured the transient suction response to obtain the SWRC using an equilibration method during both drying and wetting cycles. The system was successfully tested using a sand, a silt, and a silty sand. Characteristic curves for both drying and wetting cycles with proper flow rates were obtained within 1–3 weeks of testing. The proposed method is, therefore, very effective for routine application in engineering practice.
Paper ID: GTJ20120027