Acceleration Time History in Mode Superposition Transient Analysis — Lesson 5

How can I apply an acceleration time history to the big mass when using the Big Mass Method in a mode-superposition transient?

Ordinarily, the mass is excited by a force equal to the acceleration times the big mass, but a more convenient way is to apply the acceleration directly with the CMACEL command which can be used to apply an acceleration to an element component consisting of just the big mass.

More information on the CMACEL command can be found here.