Can you please show how to properly use the SELECT OPTIMIZED command ?
Here is a sample input for the SELECT OPTIMIZED...PARAMETER 1CODE AISC UNIFIED 2005METHOD ASDFIXED GROUPGROUP MEMB 1 TO 10GROUP MEMB 11 TO 20 GROUP MEMB ...SELECT OPTIMIZEDPERFORM ANALYSISCHECK CODE ALL
The SELECT OPTIMIZED command actually is equivalent to the following internal steps
CHECK CODE ALLSELECT ALLPERFORM ANALYSISSELECT ALL
The FIXED GROUP specified ahead of the SELECT OPTIMIZED ensures that the sections are grouped after the final SELECT ALL command ( processed internally as part of the SELECT OPTIMIZED command ). The PERFORM ANALYSIS after SELECT OPTIMZED ensures that the structure is re-analyzed based on the sections after the grouping which would result in redistribution of member forces. The final CHECK CODE checks whether the final sections are able to satisfy the code check based on the redistributed member forces.