Q: How can I analyze a situation where extra braces are added after cargo has been placed on a barge?
REV 7.00

A: I suppose you are asking how you can get a solution in the time domain which has the effect of the extra braces on dynamics, but not the incorrect effect on statics. This can be accomplished as follows:

   STRUCT

       LCASE -PROCESS BEFORE 0

       SSOLVE

   END

   MEDIT

       ~BRACE TUBE 36 1

       BEAM ~BRACE *B1 *C1

   END

   STRUCT

       LCASE -PROCESS AFTER 0

       SSOLVE

   END

   TDOM

   STRUCT

       LCASE -PROCESS T010 10

       SSOLVE

   END

   STRPOST

       CASES -COMBINE A010 T010 1. BEFORE 1. AFTER -1

       BEAM CODE -LOAD A010

Here we make three trips through the structural solver:

• The first captures the correct static situation before the braces are added,
• The second captures the incorrect static situation after the braces are added (the braces have static load here), and
• The last captures the incorrect dynamics.

The CASES -COMBINE fixes the problem. Here, the "incorrect" static situation is subtracted from the dynamics and the "correct" static situation is added.