报告摘要
Despite the apparent simplicity of the governing physics at the micro-scale where grains can be modeled as solid bodies interacting through contacts, the constitutive modelling of granular materials composed of huge numbers of solid bodies remains highly challenging. In particular, the failure modes exhibited by such materials are often difficult to anticipate with standard modelling tools. The complex behavior of granular materials at macroscale (engineering scale) stems from the coupling between the local physical interactions between grains (contact scale) and geometrical effects as grains rearrange to form complex structures at meso-scale as well as at the representative elementary volume (REV) level. The change of scale in granular materials implies to switch from a discrete to a continuum modeling framework. In the homogenization process new properties emerge from collective effects but at the same time a great quantity of information related to microstructure geometry is lost.
In this presentation I will show i) how we can define appropriated meso-structures of a few grains to understand the local physics responsible for the emerging properties in granular materials, and ii) how we can include this knowledge to develop micro-mechanical models with the minimal microstructure ingredients to reflect the complex mechanical behavior of granular material. In particular, I will show how such a modeling strategy can be used to make critical state or capillary stresses to emerge in micromechanical models. I will also show how micromechanical models accounts easily for the particular failure modes though static liquefaction.
主讲人简介
After graduating from the Ecole Polytechnique (France) in 2014 and from the Ecole Nationale des Ponts et Chaussees (France) in 2015, Dr. Antoine WAUTIER has completed his studies by Ph.D. at IRSTEA in 2018. After his defense, he joined INRAE in 2018 as a permanent researcher and engineer to pursue his research on the modeling of emerging properties in geomaterials thanks to multi-scale constitutive models. His research topics includes in particular i) internal erosion and filtration in relation with the potential for static liquefaction, ii) critical state and related microstructure reorganization, iii) capillary stress from capillary bridges. Most of his research builds on the use of DEM simulations as a tool to extract the elementary physics of granular material. These results feed the construction of multi-scale models based on statistical homogenization. So far he has co-authored more than 30 papers and co-supervised 8 PhD candidates. In addition to his fundamental research activities, he also provides applied expertise services for the French government concerning dam safety, and he is involved in teaching activities dedicated to undergraduate students, master students, PhD candidates and professional engineers.
协办单位：浙江省力学学会岩土力学与工程专业委员会、浙江省岩土力学与工程学会本构理论与数值分析专业委员会、浙江大学岩土工程计算中心