Understanding the micro mechanical behavior of granular material under stress controlled undrained cyclic loading using DEM

The research project aims to explore the mechanism of different kinds of behavior of granular material under stress-controlled cyclic loading from a micro mechanical perspective and to establish a new constitutive model incorporating the micro parameters, e.g. fabric. The reasonability of some existing failure criteria will be evaluated from a micro mechanical point of view. Detailed micro-scale analyses will be completed including evolution of the probability distribution function (PDF) that describes the contact forces in the material, the evolution of the fabric anisotropy and variation in the coordination number. It will then provide a thorough understanding of the undrained behaviour of sand under stress controlled cyclic loading and give a more reliable guidance to the practical design of offshore foundations.