A simplified DEM numerical simulation of vibroflotation without backfill

International Symposium on Geohazards and Geomechanics 2015

地球科学;生态环境科学

Jiang, M.J.^1,2,3 ; Liu, W.W.^1,2,3 ; He, J.^1,2,3 ; Sun, Y.^1,2,3

State Key Laboratory for Disaster Reduction in Civil Engineering, Tongji University, Shanghai

200092, China^1

Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education, Tongji University, Shanghai

200092, China^2

Department of Geotechnical Engineering, College of Civil Engineering, Tongji University, Shanghai

200092, China^3

关键词: Deformation and failures;    Discrete mechanics;    Geological disaster;    Ground reinforcement;    In-situ experiments;    Mechanical response;    Reinforcement mechanisms;    Resistance modeling;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/26/1/012044/pdf
DOI  :  10.1088/1755-1315/26/1/012044

学科分类：环境科学（综合）

来源: IOP

【 摘 要 】

Vibroflotation is one of the deep vibratory compaction techniques for ground reinforcement. This method densities the soil and improves its mechanical properties, thus helps to protect people's lives and property from geological disasters. The macro reinforcement mechanisms of vibroflotation method have been investigated by numerical simulations, laboratory and in-situ experiments. However, little attention has been paid on its micro - mechanism, which is essential to fully understand the principle of the ground reinforcement. Discrete element method (DEM), based on discrete mechanics, is more powerful to solve large deformation and failure problems. This paper investigated the macro-micro mechanism of vibroflotation without backfill under two conditions, i.e., whether or not the ground water was considered, by incorporating inter-particle rolling resistance model in the DEM simulations. Conclusions obtained are as follows: The DEM simulations incorporating rolling resistance well replicate the mechanical response of the soil assemblages and are in line with practical observations. The void ratio of the granular soil fluctuates up and down in the process of vibroflotation, and finally reduces to a lower value. It is more efficient to densify the ground without water compared to the ground with water.