Two modifications for the basic Barcelona model(BBM) are present. One is the replacement of the net stress by the average skeleton stress in unsaturated soil modeling, and the other is the adoption of an expression fo...Two modifications for the basic Barcelona model(BBM) are present. One is the replacement of the net stress by the average skeleton stress in unsaturated soil modeling, and the other is the adoption of an expression for the load-collapse(LC) yield surface that can match flexibly the normal compression lines at different suctions. The predictions of the modified BBM for the controlled-suction triaxial test on the unsaturated compacted clay are presented and compared with the experimental results. A good agreement between the predicted and experimental results demonstrates the reasonability of the modified BBM. On this basis, the coupled processes of groundwater flow and soil deformation in a homogeneous soil slope under a long heavy rainfall are simulated with the proposed elasto-plastic model. The numerical results reveal that the failure of a slope under rainfall infiltration is due to both the reduction of soil suction and the significant rise in groundwater table. The evolution of the displacements is greatly related to the change of suction. The maximum collapse deformation happens near the surface of slope where infiltrated rainwater can quickly reach. The results may provide a helpful reference for hazard assessment and control of rainfall-induced landslides.展开更多
A coupled solid-fluid FE-model for partially saturated soils,characterized by modeling the soil as a three-phase material consisting of a deformable soil skeleton and the fluid phases water and air,is reviewed briefly...A coupled solid-fluid FE-model for partially saturated soils,characterized by modeling the soil as a three-phase material consisting of a deformable soil skeleton and the fluid phases water and air,is reviewed briefly.As a constitutive model for the soil skeleton,the well-known Barcelona Basic model(BBM)is employed,which is formulated in terms of net stress and matric suction.For the BBM,a computationally efficient return mapping algorithm is proposed,which only requires the solution of a scalar nonlinear equation at the integration point level.The coupled FE-model is applied to the coupled transient numerical simulation of the water flow and the deformations and stresses in an embankment dam.展开更多
基金Project(1301015A)supported by the Post-doctoral Research Fund of Jiangsu Province,ChinaProject Funded by the Priority Academic Program of Jiangsu Higher Education Institution,China+1 种基金Project(2014M561566)supported by China Postdoctoral Science FoundationProject(YK913007)supported by Key Laboratory of Earth-Rock Dam Failure Mechanism and Safety Control Technologies,China
文摘Two modifications for the basic Barcelona model(BBM) are present. One is the replacement of the net stress by the average skeleton stress in unsaturated soil modeling, and the other is the adoption of an expression for the load-collapse(LC) yield surface that can match flexibly the normal compression lines at different suctions. The predictions of the modified BBM for the controlled-suction triaxial test on the unsaturated compacted clay are presented and compared with the experimental results. A good agreement between the predicted and experimental results demonstrates the reasonability of the modified BBM. On this basis, the coupled processes of groundwater flow and soil deformation in a homogeneous soil slope under a long heavy rainfall are simulated with the proposed elasto-plastic model. The numerical results reveal that the failure of a slope under rainfall infiltration is due to both the reduction of soil suction and the significant rise in groundwater table. The evolution of the displacements is greatly related to the change of suction. The maximum collapse deformation happens near the surface of slope where infiltrated rainwater can quickly reach. The results may provide a helpful reference for hazard assessment and control of rainfall-induced landslides.
基金Financial support by a scholarship for young researchers granted by the University of Innsbruck to the second author is gratefully acknowledged.
文摘A coupled solid-fluid FE-model for partially saturated soils,characterized by modeling the soil as a three-phase material consisting of a deformable soil skeleton and the fluid phases water and air,is reviewed briefly.As a constitutive model for the soil skeleton,the well-known Barcelona Basic model(BBM)is employed,which is formulated in terms of net stress and matric suction.For the BBM,a computationally efficient return mapping algorithm is proposed,which only requires the solution of a scalar nonlinear equation at the integration point level.The coupled FE-model is applied to the coupled transient numerical simulation of the water flow and the deformations and stresses in an embankment dam.