Experimental Study of Small Strain Stiffness Properties of Soil

Abstract:

Small strain stiffness properties of soil play an important role in predicting the deformation of deep foundation pit and tunnel excavation. This paper used oedometer, stress path triaxial apparatus, and resonant column apparatus to measure the small strain stiffness properties of three typical undisturbed soils in Changzhou, Jiangsu province. The parameters involved in the hardening soil model combined with the small strain model (HSS), including the initial shear modulus, modulus reduction curve, the soil strength parameters, and unloading and reloading modulus, were determined. The influence of effective stress on small strain stiffness properties was also studied, and suggestions were proposed on how to choose suitable small strain model parameters.

Key words:stiffness of soil; small strain hardening model; oedometer test; triaxial test; resonant column