Hi Arash Mohammadzadeh,

Your question is really general but you can define this specific loading in "amplitude module" with "solution dependent" tool or use subroutine UAMP in ABAQUS.

I'll Hope this help you.

Regards,

Azadeh

That you for your help,

I mean that I want to make a function between input and output,

For example, makeing a force function for a cantilever beam which is dependent on y-displacement, 

Shuch as this function.

Mx"+cx'+kx=f (x)

Actually I want add a force function which is depending on resulat (y displacement)