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New features available in Udec 4.0

 

  1. Graphical User Interface
    A new graphical user interface, the GIIC (Graphical Interface for Itasca Codes), makes all features in UDEC available by using graphical tools. The UDEC command line interface is unchanged and is still available. Features in the GIIC help users graphically define the geometry and jointing of the model. Placement of structural support and boundary conditions is easier and more accurate. There is a data base of material properties.
  2. Extended and User Defined Zone Models
    A new option is available in UDEC that allows external zone constitutive models to be written in C++ and compiled as DLL (dynamic link library) files that can be loaded whenever needed. C++ DLL models run nearly as fast as the build in models in UDEC. In addition 19 previously written constitutive models are available as part of this option. This new feature is accessed via the CONFIG cppudm and ZONE model load commands). DLLs written by other users can be accessed via Itasca's web site.
  3. User Defined Joint Models
    As part of the UDM option described above, joint constitutive models may also be compiled as DLL files. This new feature is accessed via the CONFIG cppudm and JMODEL model load commands). DLLs written by other users (when available) can be accessed via Itasca's web site.
  4. Block Hide and Show
    Individual and groups of blocks may be hidden in UDEC. This can be used for visual effect but is also a very powerful tool in controlling model generation. Most commands such as cutting of joints, zone generation, and property assignment will be limited to visible blocks.
  5. Two Phase Flow
    UDEC can now perform joint fluid flow simulations involving displacement of a fluid by another. Two-phase flow processes have important applications in fields as diverse as the oil industry, agriculture, pollution control, waste disposal, and slope stability. In the UDEC formulation, the two fluids are considered immiscible and slightly compressible (i.e., spatial variations of densities are neglected).
  6. Block fill
    A more robust process for excavate and fill has been implemented in     UDEC. In this new procedure, excavated blocks are deleted rather than replaced by a null zone model. When backfill is needed, the BLOCK fill command is used to replace the excavation void with a newly created block. This new blocks can be cut and zoned and assigned stresses and material properties. The new block will conform to the displaced geometry of the excavation. The new block may also be trimmed at the top to simulate incomplete filling of the void.
  7. Groups
    A new command, GROUP, is now available to identify sets of blocks, zones, or contacts (joints). The group name is a text string. The name is assigned to the objects in a selected range. Groups can be used in ranges to limit the actions of specific commands. Groups for blocks, zones and contacts may be plotted.
  8. Factor of Safety Calculation
    A new command SOLVE fos has been added to allow the calculation of a factor of safety in the model. The strength reduction method for determining the factor has been implemented. The user has control over specific zone and joint properties to be reduced in the calculation.
  9. Solve Elastic
    A new command, SOLVE elastic has been added to make it easier to perform initial equilibrium calculations. The user may assign real properties to the zones and then use this command to bring the model to elastic equilibrium. This is also useful following excavation to prevent the tensile shock wave caused by instant removal of material from failing nearby zones.
  10. Crack Table Command
    The creation of complex shapes in     UDEC is made easier by this new command. The user simply puts the coordinates of the shape of the object into a table and UDEC will generate the shape.
  11. Network key
    The network key allows a single hardware dongle to be placed at a central location. Individual users may then run     UDEC from any computer on the network. Network keys require a special licensing arrangement and installation. Contact Itasca for details.
  12. Mixed Discretization
    Mixed discretization has been added to     UDEC to improve large strain plastic deformation calculations. This feature is implemented by subdividing each of the regular triangular zones in UDEC into quadratic zones.
  13. Plotting of Fish Extra Variables
    There is an extra unused variable in each of the     UDEC data structures that may be used to store information. This is accessed through the FISH language. The extra variables for the data structures for zones (z_extra), contacts (c_extra), and grid points (gp_extra) may now be plotted.
  14. Ability to Link UDEC to Other Itasca Codes via TCP/IP connection
    With     UDEC 4.0 data can be passed rapidly between two or more Itasca codes running on the same machine. All other Itasca codes also have this capability. One possible application would be embedding PFC2Dparticles inside an excavation in UDEC thus providing an efficient boundary condition for the ball assembly. The data transmission between codes is invoked by the SOCKET IO FISH functions that allow large arrays of data to be exchanged with a single command.
  15. Structural Element Enhancements
    Hydrostatic loads on structural elements may be specified. This allows the loads due to external or internal fluid pressures to be added to the stresses in the elements. This is useful for pressure tunnels and for tunnel liners. Previously the hydrostatic loads had to be added by hand or by a FISH function. The effect of thermal expansion has been added for beams and cables. New commands have been added to give grater flexibility in the application of beams. The user may specify exactly where the beams should be placed. Cables will now automatically adjust the placement of the nodes to avoid being on block or zone boundaries or slightly outside of a block.
  16. New Ranges
    Several new range keywords have been added to make model construction easier. These include objects:
    - left, right, above, or below of a line or a boundary defined in a table;
    - inside or outside of a perimeter defined in a table of coordinates;
    - in groups;
    - contacts between groups
    - contacts between hidden and visible blocks.
  17. Double precision version
    UDEC     4.0 includes a double precision code as well as a single precision code. The double precision version provides more accurate solutions in the cases in which the accumulated value of a variable after many thousands of timesteps is much larger than the incremental change in the variable (e.g. an accumulated value for displacement that is roughly six orders of
    magnitude than the incremental value in a creep calculation). The double precision version is also recommended for models that have coordinates that are large compared to the typical zone or block dimension.
  18. Projected and block fill stress contour plots.
    The sampling technique used in     UDEC prevents plotting of fill contours up to non-orthogonal boundaries. In UDEC 4.0 the stress can be projected to the grid points allowing fill stress contours to fill the entire model boundary. The block fill is another new option which fills each zone with a color corresponding to the one stress.