Since the design of the subsoiler is a complex work,the interaction between the subsoiler and soil was investigated by using Distinct Element Method(DEM)in this study.Based on the traditional discrete element theory,t...Since the design of the subsoiler is a complex work,the interaction between the subsoiler and soil was investigated by using Distinct Element Method(DEM)in this study.Based on the traditional discrete element theory,the 3D model of soil particles and the subsoiler were established after considering the liquid bridge force between soil particles.The operating resistance curves of the subsoiler were achieved after the DEM simulation at a speed of 1 m/s,and three depths of 180 mm,220 mm and 260 mm,respectively.The simulation curves agreed well with the field experimental results based on relative errors of 2.96%,14.95%and 7.15%,respectively,at three depths.All these data proved that it was feasible and favorable to analyze the performance of the subsoiler by using the DEM and it is of important significance for studying and further optimizing the structure of the subsoiler.展开更多
This paper presents a numerical investigation on the strain localization of an idealized sand in biaxial compression tests using the distinct element method(DEM).In addition to the dilatancy and material frictional an...This paper presents a numerical investigation on the strain localization of an idealized sand in biaxial compression tests using the distinct element method(DEM).In addition to the dilatancy and material frictional angle,the principal stress field,and distributions of void ratio,particle velocity,and the averaged pure rotation rate(APR)in the DEM specimen are examined to illustrate the link between microscopic and macroscopic variables in the case of strain localization.The study shows that strain localization of the granular material in the tests proceeds with localizations of void ratio,strain and APR,and distortions of stress field and force chains.In addition,both thickness and inclination of the shear band change with the increasing of axial swain,with the former valued around 10-14 times of mean grain diameter and the later overall described by the Mohr-Coulomb theory.展开更多
基金This study was funded by the National Science and Technology Supporting Plan(No.2011BAD29B08)the“111”Project(No.B12007).
文摘Since the design of the subsoiler is a complex work,the interaction between the subsoiler and soil was investigated by using Distinct Element Method(DEM)in this study.Based on the traditional discrete element theory,the 3D model of soil particles and the subsoiler were established after considering the liquid bridge force between soil particles.The operating resistance curves of the subsoiler were achieved after the DEM simulation at a speed of 1 m/s,and three depths of 180 mm,220 mm and 260 mm,respectively.The simulation curves agreed well with the field experimental results based on relative errors of 2.96%,14.95%and 7.15%,respectively,at three depths.All these data proved that it was feasible and favorable to analyze the performance of the subsoiler by using the DEM and it is of important significance for studying and further optimizing the structure of the subsoiler.
基金This research was financially supported by the National Natural Science Foundation of China(Grant Nos.50679057 and 10972158).
文摘This paper presents a numerical investigation on the strain localization of an idealized sand in biaxial compression tests using the distinct element method(DEM).In addition to the dilatancy and material frictional angle,the principal stress field,and distributions of void ratio,particle velocity,and the averaged pure rotation rate(APR)in the DEM specimen are examined to illustrate the link between microscopic and macroscopic variables in the case of strain localization.The study shows that strain localization of the granular material in the tests proceeds with localizations of void ratio,strain and APR,and distortions of stress field and force chains.In addition,both thickness and inclination of the shear band change with the increasing of axial swain,with the former valued around 10-14 times of mean grain diameter and the later overall described by the Mohr-Coulomb theory.
