×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Multiple Load Cases in Abaqus

Multiple Load Cases in Abaqus

Multiple Load Cases in Abaqus

(OP)
Hello,
I am wondering how to accomplish the below in Abaqus Standard/CAE.

Lets say I have a structure (aircraft interior monument) and I want to analyze the above structure for different emergency inertial factors (Forward 9.0g, Aft 3.0g etc). The loading is input as inertial (I need to check the correct term in Abaqus CAE). And I may need to perform non-linear (geometrical) analysis. In FEA packages similar to Abaqus, I can create multiple load cases and assign a different job card for each case and analyze all of these load cases simultaneously but independently. And I can post-process each of the above load cases in the same FEA session (i.e. all the results from different load cases will be contained in one single output file).

I realize that I can create load cases for Static Perturbation step but I believe only linear analysis is supported by the above function.

Any inputs on how I can accomplish load cases in Static General step?

I can create 4 separate steps but I am afraid that subsequent steps may use conditions or state of the structure from the previous steps. Am I correct in understanding how steps work in Abaqus? I want each load case to be independent of each other and start at original state (undeformed).

RE: Multiple Load Cases in Abaqus

If you use the "OP=NEW" option when defining loads and boundary conditions for each steps, it should reset rather than carry over previous definitions.

RE: Multiple Load Cases in Abaqus

(OP)
Thanks. Is there any way the above can be specified in the GUI rather then entering keywords manually?

RE: Multiple Load Cases in Abaqus

Probably, but I don't work in the GUI much, so I can't help you there. Shouldn't be hard to modify the .inp that gets written out though.

RE: Multiple Load Cases in Abaqus

(OP)
Where in the input file would I specify the above keyword? Step definition?

RE: Multiple Load Cases in Abaqus

It's an option on your loading and BC keywords, not a standalone keyword. So it'd look something like *CLOAD, OP=NEW

RE: Multiple Load Cases in Abaqus

When the behavior is nonlinear, then the steps built up on each other. So using OP=New is only ok when the effect from the previous step disappears in the next one. If you have plasticity or other path dependent behavior, then you can't do that.

You have to run the jobs independent of each other in separate analysis.
If you have a preload step that is common for all, then you can use *Restart to start a new analysis with the specific configuration of another analysis.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources