Uncracked mesh

The uncracked mesh can be created in any suitable pre-processor for the finite element interface that is being used for the analysis. Zencrack simply uses the ASCII input file that would be used for analysis of the uncracked mesh by the finite element code e.g. the .inp file for Abaqus or the .ans file for Ansys.

The uncracked mesh contains all relevant material definitions, boundary constraints, loading and any other data necessary to generate a valid input file for the uncracked specimen.

The mesh must be constructed in such a way that the required initial defect(s) can be inserted by replacement of one or more elements in the mesh by crack-blocks. If the analysis is based on an existing mesh it may be possible to re-use the mesh with little or no modification. If starting from a blank sheet of paper it is usually best to sketch out the required meshing in the crack region before starting the creation of the model. This is particularly true in a crack growth analysis for which the mesh must be sensible for the initial crack and some anticipated larger crack.