Selection of Soil Models and Parameters for Geotechnical Engineering Application

Abstract

The mechanical behaviour of soils may be modelled at various degrees of accuracy. Hooke's law of linear, isotropic elasticity may be thought of as the simplest available stress-strain relationship, but this is generally too crude to capture essential features of soil behaviour. On the other hand, a large number of constitutive models have been proposed by several researchers to describe various aspects of soil behaviour in detail. However, the more sophisticated a soil model is, the more parameters have to be selected on the basis of soil investigation data. For geotechnical engineering applications soil data is usually limited to results obtained from basic field tests. There is often insufficient data to accurately select all parameters of fancy models. As a result, some parameters should be `estimated' and it can be argued whether such models deliver in practice the accuracy that they pretend. In between Hooke's law and fancy models there is a range of existing models that could be used within the finite element method for geotechnical engineering applications. In this contribution possibilities and limitations of such models are discussed with the purpose to give geotechnical engineers (rather than researchers) guidelines to properly select soil models and their corresponding parameters to be used in the finite element method for engineering applications.