What's New in Zencrack?

Zencrack 7.3

Zencrack version 7.3 was finalised on 21 April 2004

Version 7.3 expands the many new capabilities introduced in version 7.2. In particular there are extensions to the post-processing capabilities and the Ansys interface.


  • a significantly reduced memory requirement for all Zencrack jobs
  • the overwrite option to delete existing job files is improved
  • a large number of error and warning messages have been updated and improved
  • the setup program for Windows is updated to allow specification of an Abaqus pre-release version and to include an Ansys "-p" run-time option for a non-default Ansys product
  • the fracture mechanics Unit conversion utility has been made more robust.
  • a number of documentation and programs bugs have been fixed.

Abaqus interface

  • the Abaqus keyword file keyabq.dat is updated for versions up to Abaqus 6.4-1.
  • Abaqus user subroutine zcr-ctint is provided (a urdfil routine) to allow extraction of Ct-integral values from the .fil file in addition to the existing option of extracting the values from the .dat file.

Ansys interface

  • the Ansys keyword file keyans.dat is updated for versions up to Ansys 8.0
  • temperature interpolation is now possible into the crack-blocks for a temperature distribution defined at all nodes in the uncracked mesh
  • if there are temperatures in the f.e. analysis then the temperatures at crack front nodes can be extracted for use in processing the results
  • transition elements can be defined when using surface based tying to incorporate crack-blocks into a model
  • Ansys solid model options can be used in the uncracked mesh batch file. In this case, the "-a solidmodel" command line should be used (otherwise the default is "-a normal")
  • spring elements can now be included in the uncracked mesh.

New utility program PROCESS

A new utility program "process" replaces the previous utility "growth". This utility:

  • generates a comma separated variable file (.csv) ready for import into a spreadsheet
  • includes options to process single or multiple crack front nodes
  • generates a file containing all data relevant to the node(s), e.g. displacement and energy based K and G results, growth magnitudes, cycles, opening displacements, raw contour integral values (Abaqus only)
  • generates data for use in preparing failure assessment diagrams
  • allows plotting of many curves including:
    • K vs a in a growth analysis
    • a vs N (and/or t) in a growth analysis
    • %error in G term vs f.e. analysis number in a growth analysis
    • K along crack front
    • K vs fe step for multi-increment fe analysis of a single crack position
  • has a MS Excel template spreadsheet included to allow results to be plotted immediately by pasting the csv output into the spreadsheet.

Utility program 3dmesh

Utility program "3dmesh" is updated as follows:

  • an Ansys output option is now available
  • an output filename can be given by the user
  • the option to use 2 or 3 noded elements along the crack front is now available for Abaqus, Ansys and Marc output
  • the generated meshes contain element sets for Abaqus, Ansys and Marc output
  • the use of offset node and element numbers in the generated mesh is improved making it easier to combine results from different runs into one file.