MPoint

MPoint is Itasca’s Material Point Method (MPM) software for simulating problems involving large deformation, material flow, failure, and contact. In MPoint, the material domain is represented by material points that carry mass, stress, strain, velocity, and constitutive-model state variables, while a temporary background grid is used to solve the governing equations of motion. This combined particle–grid formulation allows MPoint to retain the history-dependent behavior of a Lagrangian method while avoiding severe mesh distortion during large deformation. MPoint provides capabilities for two- and three-dimensional analysis, static and dynamic calculations, constitutive-model assignment, particle generation from zones or geometric ranges, boundary-condition application, damping, history recording, and results visualization. Models can be created and controlled using commands and FISH functions, allowing users to develop reproducible workflows for geomechanics, structural response, impact, collapse, granular flow, and other large-deformation applications.

Guide to the MPoint Documentation

The MPoint Help documents contain the complete documentation for the software.

  • The documentation is accessible instantly and directly from the software (use the Help ‣ Help menu command).

  • It is integrated with the commands and FISH functions via the Inline Help utility; access to reference documentation is nearly instantaneous and fully targeted.

  • It contains a built-in Search box at the top right of any page.

  • Material in the documentation can be easily copied and pasted if needed.

  • A feedback mechanism allows users to provide comments on the material presented (see the link “Was this helpful? …” at the bottom of every page).

The organization of this section of the MPoint documentation is as follows.

MPoint Modeling

This section is a user’s guide specific to MPoint. It provides a general Introduction to MPoint2D and MPoint3D. The tutorials and introductory modeling examples that follow are the best place to begin gaining hands-on experience with the softwares. The modeling material examines the major steps in the MPoint modeling process, including definition of the computational domain, creation of the background grid, generation or import of material points, assignment of constitutive models and material properties, application of boundary conditions and loading, contact, hybrid modeling, cycling, solution control, and interpretation of results.

MPoint Theory and Background

The theoretical formulation for MPoint is described in detail in this section. This includes the mathematical description of the Material Point Method, the Lagrangian material description, the Eulerian background grid, particle-to-grid and grid-to-particle transfer operations, the equations of motion, interpolation procedures, kinematic updates, constitutive integration, and numerical implementation.

MPoint Examples

This section describes numerical simulation procedures and capabilities available in MPoint2D and MPoint3D. It provides information on model setup, material-point generation, background-grid resolution, loading and boundary conditions, damping, PIC-FLIP transfer, contact, large deformation, material-point splitting, volume control, hybrid modeling, and other numerical procedures used in MPoint analyses.

Options

This section describes the program options for MPoint

Commands

This section provides reference documentation for the commands used to create, configure, execute, monitor, and post-process MPoint2D and MPoint3D models.

FISH Functions

This section provides reference documentation for the FISH functions associated with MPoint objects and calculations. These functions may be used to inspect and modify material points, background-grid nodes, model states, properties, histories, and other quantities during model construction and execution.

Sketch (formerly Extrude)

This section describes the Sketch facility used for interactive geometry construction, grouping, discretization, and preparation of model geometry. Sketches may be created interactively or through commands and FISH functions and may be incorporated into the model-building workflows available in Itasca software.

In This Section

Base Commands

The main commands used by MPoint are encapsulated on the list below. Note these are a mix of MPoint-specific commands and commands that are also commonly used by PFC, 3DEC and FLAC3D.

Table 1: MPoint Commands

c data

c model

c dfn (discrete fracture network)

c mpoint

c domain

c plot

c fish

c program

c geometry

c project

c group

c table

c history

User Support

We believe that the support Itasca provides to code users is a major reason for the popularity of our software. We encourage you to contact us when you have a modeling question. We will provide a timely response via phone, email or fax. General assistance in the installation of MPoint on your computer, plus answers to questions concerning capabilities of the various features of the code, are provided free of charge. Technical assistance for specific user-defined problems can be purchased on an as-needed basis.

The first place to look for support is through the Technical Support Dialog built into the user interface, available in the software menu at “Help/Request Technical Support…”

If that does not work for some reason, or if you wish to communicate via phone or email, please contact us.

Itasca Consulting Group
111 Third Avenue South, Suite 450
Minneapolis, Minnesota 55401 USA
Phone: (+1) 612-371-4711
Fax: (+1) 612-371-4717
Email: software@itascacg.com
Web: www.itascacg.com

We also have a worldwide network of code agents who provide local technical support. Details may be obtained from Itasca. Note that, in general, we prefer to provide support via email, and we will also generally forward your question to the software agent responsible for your region.

More information about support and related tasks (updating the software, identifying version and license numbers, etc.) is available in the Support sub-section of the Program Guide section.