This paper describes the development and application of inflow and outflow boundary conditions (BCs) for the material point method (MPM) in order to simulate fluid flow problems. This corresponds to velocity and pressure controlled BCs. Due to the coupled Lagrangian and Eulerian description of the fluid motion in MPM it is necessary to add and remove material points, with appropriate kinematic properties, to and from the computational domain. The newly-developed BCs have been used to simulate uniform open channel flow and the phenomenon of free overfall in open channels, which is transient conditions leading to non-uniform flow due to a sudden bed level drop. It is shown that the numerical results predict well the flow geometry including end depth ratio, pressure distribution and accelerations, therefore the velocities and displacements.@en

This paper describes current work on the implementation of non-trivial boundary conditions (BCs) for improving the general applicability of the Material Point Method (MPM) to geotechnical boundary values problems. It summarises novel boundary treatments (non-trivial BCs) in MPM for (i) flow conditions, as well as (ii) the application of a surface traction on a moving boundary for solid materials. Both treatments are required, for example, to estimate the consequence of slope failure in geotechnical engineering. the flow condition BCs have been used to stimulate a subcritical flow and the surface traction BC has been applied on top of aslope leading to failure. Both examples show that these new treatments are useful in solving practical problems.@en

Dike infrastructure is of vital importance for the safety against flooding. The standard methodologies for the assessment of dike safety for macrostability are based on limit equilibrium methods, which result in a safety factor against shear failure. The more advanced alternative consists of using finite element method to compute the safety factor against shear failure. However, these approaches do not take into account the capacity of the dike to retain water, but are only concerned with the mechanical equilibrium of the dike's initial composition. With the recent advancements in the modelling of large deformations within geotechnical engineering, e.g. by means of the material point method, the post failure behaviour of the dike can be predicted. The material point method is a mesh-free method that has been developed to address the problem of large deformation on a continuum level. The material point method offers the possibility to redefine the concept of factor of safety against shear failure. The initial shear failure of a dike does not necessarily lead to the loss of the dike's capability to retain water. In reality, after the initial shear failure the mass of soil will move and reach a new equilibrium position. This paper, after a brief description of the material point method, presents the analysis of a progressive dike failure, where the post failure behaviour is examined and a proposal is made to redefine the concept of factor of safety.@en

The main aim of this paper is to describe and analyse the modelling of vertical column tests that undergo fluidisation by the application of a hydraulic gradient. A recent advancement of the material point method (MPM), allows studying both stationary and non-stationary fluid flow while interacting with the solid phase. The fluidisation initiation and post-fluidisation processes of the soil will be investigated with an advanced MPM formulation (Double Point) in which the behavior of the solid and the liquid phase is evaluated separately, assigning to each of them a set of material points (MPs). The result of these simulations are compared to analytic solutions and measurements from laboratory experiments. This work is used as a benchmark test for the MPM double point formulation in the Anura3D software and to verify the feasibility of the software for possible future engineering applications.

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The main aim of this paper is to describe and analyse the modelling of vertical column tests that undergo fluidisation by the application of a hydraulic gradient. A recent advancement of the material point method (MPM), allows studying both stationary and non-stationary fluid flow while interacting with the solid phase. The fluidisation initiation and post-fluidisation processes of the soil will be investigated with an advanced MPM formulation (Double Point) in which the behaviour of the solid and the liquid phase is evaluated separately, assigning to each of them a set of material points (MP's). The result of these simulations are compared to analytic solutions and measurements from laboratory experiments. This work is used as a benchmark test for the MPM double point formulation in the Anura3D software and to verify the feasibility of the software for possible future engineering applications.

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