Reporting topic：Hydro-mechanical modelling of gap-graded soils considering internal erosion
Reporter: Professor Yin Zhenyu, Department of Civil and Environmental Engineering, Hong Kong Polytechnic University
Reporting time：16:00-17:00 p.m. on April 14, 2023
Reporting place：Room 1114, Science Building
Brief introduction of reporter：
尹振宇，香港理工大学土木与环境工程系教授，1997年获浙江大学建筑工程专业学士学位，之后在浙江嘉华建筑设计有限公司工作过5年，于2003年、2006年分别获得法国南特中央理工大学岩土工程专业硕士和博士学位（博士期间在同济大学做过联合培养）。曾于2011年入选上海市特聘教授“东方学者”；兼任美国土木工程师协会（ASCE）“粒状材料专业委员会”理事；任欧洲环境与土木学报(EJECE)、Geotechnique Letters副主编；日本土工（S & F）、加拿大土工（Can.Geot. J.）、ASCE-IJOM、Acta Geotechnica、Transportation Geotechnics、Computers and Geotechnics、GeoRisk等期刊编委；主要从事土力学与岩土工程方面的教学和研究，近年来在国际核心刊物上发表SCI论文250余篇，WOS的H指数为51。连续多次入选全球前2%顶尖科学家榜单。尹振宇教授的主要研究方向有：（1）土体宏微观特性及本构关系；（2）岩土工程模型试验及大变形数值分析；（3）人工智能在岩土工程中的应用。具体信息请查阅课题组主页http://geoinvention.com/。
Summary of report：
This study attempts to formulate a coupled numerical model in the framework of continuum mechanics in order to investigate the phenomenon of internal erosion and its consequences on the mechanical behaviour of soils. For this purpose, a four-constituent numerical approach has been developed to describe the internal erosion process. The detachment and transport of the fine particles have been described by a mass exchange formulation between the solid and fluid phases. The stress-strain relationship of the soil is represented by a non-linear incremental model. Based on experimental data, this constitutive model has been enhanced by the introduction of a fines content dependent critical state, which allows accounting for the influence of fines on soil deformation and strength. The applicability of the numerical approach to capture the main features of the internal erosion process and its impact on the mechanical behaviour of the eroded soil has been validated by comparing numerical and experimental results of internal erosion tests on HK-CDG mixtures, which demonstrated that the model was able to reproduce with good accuracy the experimental data. Furthermore, the influence of the stress state, the initial soil density, and the initial fraction of fines have been analysed through numerical simulations.
