An Elastoplastic Model for Unsaturated Rockfills and its Simulations of Laboratory Tests

• Published in: SOILS AND FOUNDATIONS Vol. 47; no. 5; pp. 919 - 929
• Main Authors: Kohgo, Yuji, Asano, Isamu, Hayashida, Yoichi
• Format: Journal Article
• Language: English
• Published: Tokyo Elsevier B.V 01.10.2007; The Japanese Geotechnical Society; Japanese Geotechnical Society
• Subjects: Applied sciences; Buildings. Public works; collapsed settlement; constitutive equation; Exact sciences and technology; Geotechnics; IGC: D4/D5/D6/E12; numerical analysis; rockfill; Soil investigations. Testing; suction; unsaturated soil; collapsed settlement; constitutive equation; rockfill; numerical analysis; suction; unsaturated soil; IGC: D4/D5/D6/E12; Constitutive equation; Suction; unsaturated soil (IGC: D4/D5/D6/E12); Experimental study; Modeling; Triaxial compression; Numerical analysis; Elastoplasticity; Soil test; Laboratory test; Numerical simulation; Unsaturated soil; Comparative study; Rockfill
• ISSN: 0038-0806; 1881-1418
• DOI: 10.3208/sandf.47.919

This paper describes an elastoplastic model for rockfills and simulations of laboratory test by using the model. Rockfills express remarkable shear strength reductions and compressive deformations due to saturation. The authors have already developed elastoplastic models to represent the mechanical properties of unsaturated soils. Two suction effects were taken into account in the models. However for rockfills, one suction effect: an increase in suction enhances yield stresses and affects resistance to plastic deformations, remarkably appears. The effect may be evaluated by formulating state surfaces. In this paper, a model proposed by authors is modified for rockfills. To verify the elastoplastic model for rockfills, simulations of oedometer and triaxial compression tests were carried out. The simulation results could well express the volume change and shear behavior of the rockfill, especially the influence of water contents.