Finite Element Modelling of Soil-Structure Interaction

Abstract

This paper presents background information relevant to the modelling of soil-structure interaction. The interaction between the structural element (i.e. pile foundation or abutments) and the soil medium is believed to have the potential to alter considerably the actual behaviour of any structure. Modelling of the structural element is rather simple and straightforward when compared to modelling the structure in interaction with soil. It is known that the structural analysis simplifies soil behaviour, while geotechnical analysis simplifies structural behaviour. The choice of an appropriate soil constitutive model may have significant influence on the accuracy of soil-structure interaction analyses. A 2D finite element analysis on a pile-cap-pile-soil model replicating actual field work was performed in this paper using OASYS SAFE to further substantiate the choice of an appropriate soil constitutive model for the purpose of soil-structure interaction modelling.

Application of Finite Element Analysis in Modeling of Bionic Harrowing Discs

“…Drawing such lessons leads us to biomimetics, where structures, characters, elements, behavior, and interaction of the biological systems based on nature can be an inspiration for a new design concept and functional principle of a machine [7]. Three-dimensional finite element model (FEM) can then be used to optimize the design with minimum costs, and is very effective when results are validated experimentally [1,8,9].…”

“…According to the Coulomb equation, the cutting resistance of soil engaging implement is given by [9]: F = Pc A + FN tan β where Pc is the adhesion force between tool and soil (N/cm 2 ), A the actual contact area (cm 2 ), FN the normal force on the interface, and β the friction angle between the tool and the soil in degrees. From Equation (1), it is seen that the main factor affecting the cutting resistance is the contact area between the tool and soil, and this was key in choosing convex domes and concave dips as a way of trying to reduce the contact area A in Equation (1) through biomimetics.…”

“…Many researchers have used the finite element method (FEM) to conduct their analyses of soil deformation. Some considered soil material as non-linear elastic, while others considered it as non-linear elastic–perfectly plastic [1,8,9,18]. For the latter, which is considered in this paper, the stress is directly proportional to strain until the yield point is reached.…”

“…Beyond the yield point, the stress–strain curve is perfectly horizontal. The Drucker–Prager elastic–perfectly plastic model is one of the material models that has been adopted for conducting a FEM analysis of the soil deformation process [1,8,9]. This model was constructed originally to investigate and solve structural problems and was subsequently used to solve those in solid mechanics [8].…”

“…Several researchers have used the Drucker–Prager model to build up FEM models of soil cutting with simple tillage tools [1,8,9]. However, a few have applied three-dimensional FEM analysis of soil deformation coupled with biomimetic design of soil tillage implements with curved surface like disc harrow.…”