Comparative Evaluation of Constitutive Models for Predicting Strain Amplitude Generated by Machine Foundations
摘要
This paper reports on a comparative study with the aim of examining the performance of three widely adopted constitutive models, namely Linear Elastic (LE), Mohr-Coulomb (MC), and Hardening Soil Small Strain (HSs) to predict the shear strain amplitude in the soil beneath a machine foundation. These predictions are compared with the threshold shear strain obtained from resonant column tests on a selected soil, which represents the boundary between amplitudes causing a purely elastic response or an accumulation of plastic strains. In the numerical simulations, PLAXIS2D has been employed. To assess soil behaviour in triaxial, oedometer, and cyclic shear tests, and evaluate the reliability of the parameters and the models’ predictive capabilities, the virtual soil lab test tools available in the numerical package have been adopted. The influence of stress amplitudes, constitutive modelling, and loading frequency on shear strains in the vicinity of the foundation is highlighted, while considering different approaches to determine shear strains in finite element (FE) simulations. While for a constant excitation frequency the investigated soil models had no influence on predicted shear strains, they are strongly frequency-dependent at higher loads.