different displacement loading on nodes using prop

[ace21]

dear feap users

I want to apply fluctuating displacement boundary conditions  with different amplitudes/frequency on chosen nodes

Is it possible to do it using prop command by defining some identifier for propotional loading for each node

I am using 8.2 ver of FEAP


thanks

[Prof. R.L. Taylor]

You can do it by using the FPRO and nodal DISP commands -- the FPRO matches specific proportional loading the the corresponding DISP (Or FORC) nodal value by dof's.  This should do what you want.

[ace21]

Dear   Prof Taylor

Thanks for the reply, I tried to look up the explaination about fpro in manual but could not completely understand it

Is it possible for you to give an example of input file, I wanted to apply different amplitude /frequency of displacement load  on nodes of a single quadrilateral element


thanks

[Prof. R.L. Taylor]

say nodes 2 and 3 are nodes you want to apply displacements.  In the mesh you have

BOUN
  2 0 1 1
  3 0 1 1  ! make the dof's fixed

DISP
  2 0 f2x f2y
  3 0 f3x f3y   ! where you give values for the 'f" you want to multiply by some time function.

FPRO
  2 0 1  2
  3 0  3 4   !  where these are proportional (time function) values for each of the displacements.

Then in the solution part you specify PROP,,1 ; PROP,,2 ; etc with the various time functions.