The following changes in Abaqus 6.9 may impact the analysis of input files from previous releases of Abaqus:

• The *RETAINED EIGENMODES option is no longer available. You now specify the modes that are included in a substructure generation analysis using the *SELECT EIGENMODES option.

• The default value for the OMEGA parameter on the *DAMAGE INITIATION option is now 1.0; in previous releases the default value was 0.1.

• The default values for parameters used to define starting subspaces in an AMS frequency extraction have changed to =1.7 and =1.1; in previous releases =1.6 and =1.3.

• The BIAS, NUMBER INTERVAL, and USER BOUNDARIES parameters have all been removed from the *FREQUENCY option; see “Removal of parallel Lanczos and Lanczos restart features,” Section 6.4, for more information.

For a complete list of changes to the Abaqus input file interface, refer to Chapter 16, “Summary of changes.”