Modelling the Mechanical Properties of a Compacted Glacial Till: Fid-Bau Portal

Modelling the Mechanical Properties of a Compacted Glacial Till

Vanapalli, Sai K. / Han, Zhong

Abstract This paper summarizes comprehensive experimental studies on the soil–water characteristic curve (SWCC) and the variation of several mechanical properties with respect to suction for a compacted glacial till collected from Indian Head, Saskatchewan, Canada (referred to as Indian Head till). The summarized mechanical properties include the shear strength, unconfined compression strength, undrained elastic modulus, and resilient modulus which were either directly measured or back-calculated from the experimental results. A unified model is used to predict the variation of the mechanical properties with respect to suction. This model only requires the information of the mechanical property at saturated condition and one reference unsaturated condition and the SWCC for prediction. The advantage of this model is that it uses one constant model parameter that does not need to be calibrated. It is demonstrated that the model is capable of reliably predicting all the mechanical properties of the compacted Indian Head till. The mechanical properties are then used in numerical software Plaxis to model the load-settlement behavior of model footing tests performed on compacted Indian Head till. There is good agreement between the measured and modelled load-settlement behavior and the bearing capacity at various suction levels. Studies presented in this paper using the unified model would be helpful for implementing the mechanics of unsaturated soils in geotechnical practice.