Arguably the most critical element in successful geotechnical numerical analysis is parameter selection. If a constitutive model is inappropriate, or the soil parameters are not obtained to a sufficiently high degree of accuracy, then the subsequent numerical analysis will not adequately reflect field behaviour and be of little value.
Obtaining appropriate parameters is not just a matter of getting results from standardised tests. It is a multi-stage process requiring careful decision making, from planning and specifying the site investigation to interpreting data and deriving soil parameters, selecting constitutive models and assessing the reliability of soil parameters in a numerical model.
The links below provide some brief guidance on key parameters for certain problems and appropriate soil tests to obtain some soil parameters. For more guidance on all the stages of obtaining parameters, refer to the NAFEMS Guidebook "Obtaining Parameters for Geotechnical Analysis".
» Critical soil parameters for typical geotechnical structures
» Laboratory parameter testing
» In situ parameter testing