Statistical estimation of relative density

A new procedure is proposed to evaluate in situ relative density using SPT values, and to quantify the uncertainty associated with that prediction. The relationship is first developed under laboratory conditions, then corrected for in situ conditions. The relationship is compared with commonly used relationships, namely the Gibbs and Holtz, Bazaraa, and Waterways Experiment Station. The predictability of the proposed relationship is better than the others when the relationships are compared to field measurements where all the relevant information is available. However, the uncertainty associated with all the predictive models is considerable.