If Coordinate Structure data records have been defined in the Coordinate data then these may also be used in defining material properties. The STRC (structure) data record enables the use of totally independent sets of geometric properties for each structure. In other words, the user geometry numbers may be the same for 2 different structures but they will be treated as separate items. If used then the geometric properties for all structures must be defined using STRC data records. If STRC is not utilized then all geometric property numbers must be unique across all structures.

The structure number has to be in columns 16-20 as shown below:

        5  7           16    21
  - --- -- ---- ------ ----- ----
  X XXX 01 STRC XXXXX     nn XXXXXX
  - --- -- ---- ------ ----- ----
        |  |               |
        |  |               |
        |  |               |
        |  |               |_(3)Structure Number.
        |  |
        |  |_(2)Mandatory Keyword.
        |
        |_(1)Optional User Identifier

(3) The structure number must start from 1 on the 1st data record and increment by 1 for each structure data record input. The number of ELM* data categories must correspond to the number of structure data records.