Horizontal and vertical ground motions at same time

[susan]

Hi all,

Could you please guide me how I can apply horizontal and vertical ground motions at the same time?

If I define:

pattern UniformExcitation 1 1 -accel $accelSeries-H;
pattern UniformExcitation 2 2 -accel $accelSeries-V;

is it enough?

Or should I define analysis commands (test, algorithm, system, ...), separately?

Thank you.

[selimgunay]

Yes you can apply all the components at the same time and your pattern commands are enough. You don't need to define analysis commands separately. This just changes the right hand side of the equation of motion, hence the external excitation.