Together with Patrick Staubach from Bauhaus-Universität Weimar, Jan Machaček and Hauke Zachert from Technische Universität Darmstadt, we perform a critical investigation of three constitutive models for clay by means of analyses of a sophisticated laboratory testing programme and of centrifuge tests on monopiles in clay subjected to (cyclic) lateral loading. Constitutive models of varying complexity – namely, the basic modified Cam Clay model, the hypoplastic model with intergranular strain (known as the clay hypoplasticity model) and the more recently proposed anisotropic visco-intergranular strain anisotropy (AVISA) model – are considered. 

From the simulations of the centrifuge tests with monotonic loading it is concluded that all three constitutive models give satisfactory results if a proper calibration of constitutive model parameters and proper initialisation of state variables is ensured. In the case of cyclic loading, the AVISA model is found to offer superior performance over the hypoplastic model with intergranular strain.

M. Tafili, P. Staubach, J. Machaček, H. Zachert, T. Wichtmann: Predictive abilities of constitutive models for clay under monotonic and cyclic loading: element tests and centrifuge experiments. Géotechnique, 2024. The paper is available at the following Link.