TINPUT error with PROP

[duchoangnguyen]

Dear Professors, dear FEAP community,

I use feap 8.1 to simulate a uniaxial tensile test. All load steps of a DIC measurement should be taken into account, which is why about 500 load steps have to be generated with PROP. With a number of more than 8 load steps I get the following error: "*ERROR* TINPUT: Too many items requested, limit = 16". Is there a way to avoid this or to increase the number of inputs?
I attached the corresponding input-file with 9 load steps.

Best regards and many thanks,
Duc Hoang Nguyen

[FEAP_Admin]

The maximum number of records on a line that you can have is 16.  If you have more you need to wrap them onto the next line so something like

Code: [Select]

BATCh
 PROP,,1
END
 2 8
 1 0.00469684375 2 0.00849425 3 0.01279115625 4 0.01708865625 5 0.0213855625 6 0.02498328125 7 0.0293803125 8 0.0316786875
 9 0.03177821875
You can continue adding time value pairs, 8 per line, until you have entered all 500 load steps.

PS: Version 8.1 is very old, you should consider upgrading to the current release.

[Prof. R.L. Taylor]

When you have so many values it is probably better to input one  t, value per line.  This is done as

batch
  prop,,n
end
  2                !  same as:  2  1
  t1 v1
  t2 v2
  t3 v3
   ....
  ! blank record

n is the number of your proportional load.

[duchoangnguyen]

Thank you very much it is working now.
The resulting displacements are in negative direction whereas, according to my understanding, they should be positive if the direction of pull is positive. Have I overlooked something?

Best regards and many thanks,
Duc Hoang Nguyen

[FEAP_Admin]

Your elements are numbered backwards.  The nodes on the elements need to be numbered counter-clockwise to match FEAP's convention.
You can renumber them or have FEAP do it for you by using the CHECk command before TIME.

[duchoangnguyen]

Thank you very much! Everything works now as intended.