报告摘要
A pivotal component of sand characterization for engineering design and the interpretation of natural phenomena is the quantification of the size distribution of its particles, as well as of their shape. While it is known that such characteristics influence the macroscopic behavior of sand, from elastic wave transmission to volume change and frictional strength, most constitutive laws for sand do not account for particle-scale attributes. This talk provides an overview of novel constitutive modeling strategies accounting for both particle geometry and inter-particle interactions. The goal is to show that most established elements of traditional constitutive laws, from plastic caps to elastic nonlinearity and rotational hardening, can be explained as outcomes of particle-scale processes, thus enabling a straightforward incorporation of features extracted from digital imaging and other micro-scale characterization protocols. First, the talk discusses the compression of sand, with emphasis on the simultaneous evolution of the size and shape of its grains. Then, the role of the packing fabric on the elastic and plastic anisotropy of sand is discussed. Finally, ongoing steps to augment the proposed fabric-dependent models to simulate shear banding and critical state are discussed. On the one hand, this class of constitutive laws explains the complex behavior of sand observed both in nature and in the laboratory and can inspire the design of new materials with tunable inter-particle interactions. On the other one, they aim to expand the predictive power of sand constitutive laws deployable for a range of applications, from geohazard assessment to energy geotechnics.
主讲人简介
Giuseppe Buscarnera is Professor of Civil Engineering at Northwestern University, which he joined in 2011. He received his B.Sc. and M.S. in Civil Engineering from the Politecnico di Milano, Italy, and a Ph.D. in Geomechanics from the Politecnico di Torino, Italy. Dr. Buscarnera's research focuses on geomechanics, geohazards, granular materials, and multi-physics of porous media. He is the PI of numerous sponsored research projects on these topics, serves as chairman of the Soil Properties and Modeling committee of the ASCE Geo-Institute, is the Editor-in-Chief of the journal Géotechnique Letters, and his research has been awarded with the Faculty Early Career Development Award (CAREER) from the National Science Foundation and the ASCE Arthur Casagrande award.
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、浙江省土木建筑学会土力学及岩土工程学术委员会