Effects of storage time on sample quality in Ballina clay

Abstract

This paper explores the effects of the storage time on the engineering properties of Ballina clay, an estuarine silty clay that represents the soft soil deposits encountered along the eastern and southern Australian coastlines, which serves as foundation material for most of the country’s transport and energy infrastructure. An experimental program was carried out to evaluate the variation in soil compressibility and soil shear strength for tube specimens retrieved with an open sampler (Shelby tube) as well as an Osterberg fixed-piston sampler. Mechanical parameters obtained from tests performed immediately after sampling are compared against those measured over a period of 1 year, to assess the influence of the storage time. Results indicate that long-term storage has small influence on the quality of Ballina clay specimens in comparison with the mechanical disturbance caused during tube penetration and extraction, which is controlled by the sampler type.

Full Paper