Determination of soil stiffness parameters at a deep excavation construction site in Kenny Hill Formation

This paper determines the residual soil stiffness parameters at a deep excavation for a basement car park in the Kenny Hill Formation. Parametric studies revealed that the horizontal wall deflection at each stage of excavation could be reasonably predicted with a simple correlation between stiffness parameters with field standard penetration tests (SPTs) N value for Hardening Soil model. The correlation between tri-axial stiffness and oedometer stiffness with standard penetration test (SPT) N value is found to be 1.5 N (MPa) with unloading-reloading stiffness three times of tri-axial stiffness. The Hardening Soil model and the correlation obtained may be applied to similar soil conditions as the Kenny Hill Formation.