UniformExcitation Vertical Direction

[sedatacemogluone]

pattern UniformExcitation 4 3 -accel 1;

I try above but when I do simulation my structure does not really move in Z direction. What I am trying to do is to include vertical component of seismic forces.

Thanks in advance.

[mhscott]

Is the model 2D or 3D?
Use direction 2 for 2D, 2 or 3 for 3D depending on if you have Y (2) as vertical or Z (3) as vertical.
Also, be sure you have mass defined in the vertical DOFs.

[sedatacemogluone]

Thanks, Professor, I forgot to assign mass in Z direction.