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Modeling
Several different boundary types are defined in Phase2 for the purpose of creating the model geometry:
All models require an External boundary. Other boundary types are defined as required.
Different boundary types in Phase2

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Modeling: Entering Geometry
Phase2 provides powerful CAD based modeling features for defining the model geometry. Boundaries can be defined by:
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drawing with the mouse
entering coordinates in a prompt line
entering coordinates in a spreadsheet dialog
importing from a DXF file or other file types
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As with most CAD programs, features such as grids, snapping, undo are all implemented to greatly simplify the process. Any person who has used a CAD program (e.g. AutoCAD) will have no problem understanding and using the Phase2 geometry modeler.
Graphical entry of excavation boundary

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Modeling: Interactive Editing
Phase2 incorporates state-of-the-art editing tools which allow you to perform simple or complex editing tasks with a few mouse clicks. Boundaries and other entities can be moved, deleted, copied, stretched etc. Convenient right-click shortcuts are available for most editing options.
Right-click editing of geometry

To see more modeling and editing shortcuts in Phase2, click here. Additional editing options are described below.
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Modeling: Simplify Boundary
When model geometry is imported into Phase2 from other sources (e.g. dxf files) it is quite common that boundaries are defined by an unnecessarily large number of vertices. This can lead to modeling, meshing or analysis problems (e.g. difficulty editing boundaries, poor quality meshes, increased compute times, etc).
The Simplify Boundary option allows you to reduce the number of vertices on a boundary, according to a user-defined criterion, so that the new boundary has fewer vertices but still adequately defines the model geometry.
Slope model with geometry defined by too many vertices

Slope model with simplified boundaries

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Modeling: Geometry Cleanup
When boundary vertices are located very close to each other, this can cause modeling problems in Phase2, particularly with the finite element mesh. This can create problems with the numerical analysis, and in the worst case, can lead to incorrect analysis results, or a model which does not compute at all.
The Geometry Cleanup option allows you to "clean up" the model geometry by merging vertices which are very close to each other into a single vertex, according to a user-defined spacing criterion.
Three vertices merged into one using Geometry Cleanup

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Modeling: Change Slope Angle
The Change Slope Angle option is a specialized editing tool which allows you to easily change the overall slope angle of a slope model. You simply choose the toe and crest of the slope, enter the change in angle, and all vertices which are connected to the slope will be moved accordingly. This allows you to easily carry out a sensitivity analysis of the overall slope angle, for slope stability analysis.

Editing the overall slope angle

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Modeling: Staging
Staging in Phase2 allows you to model the sequential removal or excavation of material, in as many as 300 separate stages. Support elements such as bolts and liners can also be sequentially added or removed. Since materials and support can behave plastically and fail, the excavation sequence can play an important role in the stability of the underground structure.
Staged model of power cavern excavation, with liner and bolt support

To create a staged model:
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enter the Number of Stages in the Project Settings dialog
define the boundaries, support, material properties, etc.
select the Stage tabs at the bottom of the Phase2 screen and perform the
desired material assignments, excavation, support installation etc., at
each stage.
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Stage tabs at bottom of Phase2 screen

Staging can be applied to most of the modeling features in Phase2. For example, material properties, loads, field stress and groundwater conditions can all be modified on a per stage basis.
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Modeling: DXF Import / Export
Boundary and support geometry can be imported into Phase2 from a DXF file with the Import DXF option. Before you import the DXF file, you can select which boundary types you would like to import.
DXF Import dialog

Boundaries can also be exported to a DXF file from Phase2.
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Modeling: Slide Import / Export
To facilitate comparison of finite element and limit equilibrium results, Slide slope stability models can be imported into Phase2, or exported from Phase2.
After importing a Slide model, you can use the Shear Strength Reduction (SSR) method in Phase2 to determine the safety factor of the slope. Slide and Phase2 can be used as complementary methods of analyzing slope stability problems.
Import Slide File option

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Modeling: Undo / Redo
Phase2 has a global undo / redo functionality which allows you to easily undo (or redo) any changes to the model. You can undo / redo multiple changes by selecting from the toolbar drop-list as shown below.
List of modeling changes in undo list

The undo / redo also applies to entities such as drawing tools and queries.
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