Creep characteristics of frozen soils: Fid-Bau Portal

Creep characteristics of frozen soils

Takegawa, K. / Nakazawa, A. / Ryokai, K. / Akagawa, S.

Abstract Consideration of the creep characteristics of frozen soil is required when it is used for the construction of retaining walls. It is generally accepted that there are three kinds of frozen soils, i.e., frozen soil without ice lenses, frozen soil with layers of ice lenses and frozen soil with needle-like ice lenses, influenced by freezing conditions and physical properties of the soil itself. This paper is a study of properties of deformation and rheological and strength characteristics of frozen soil, with an unconfined compression creep test and an unconfined compression test. The test results show that existence of alternate ice layers in the frozen soil affects properties of deformation rather than those of strength. Generally, elastic strain appears instantaneously upon loading and deformation increases with the lapse of time, finally leveling off to a certain value as long as the load is below a limited value. Stress at the time of the greatest of of the leveling-off strains is called an upper yield value σu It was found that, when a stress applied to frozen soil without ice lenses is below the upper yield value mentioned above:(1) Strain is linear to time lapse expressed in logarithms. (2) Strain is linear to the stress applied.