×
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

Non linear analysis

Non linear analysis

Non linear analysis

(OP)
Hi!

I'm just trying to perform a non linear analysis with Gt Strudl, namely taking into account geometric non linearities.
Previously I did a response spectrum analysis and I transformed the results in a Pseudo static loads. After I combine these Pseudo static loads with other static loads by means of the command FORM LOAD. When I tried to perform the non linear analysis, the results miss the seismic part (the contribution to the final internal actions coming from the seismic loads is zero). It's like either the FORM LOAD command can't consider Pseudo static loads or the non linear analysis can't work with Pseudo Static Loads.
I'll write here a piece of the program:

PERFORM RESPONSE SPECTRUM ANALYSIS

COMPUTE RESPONSE SPECTRUM DISPLACEMENTS ACCELERATIONS FORCES REACTIONS MODE COMBINATION CQC
CREATE PSEUDO STATIC LOAD 'Ed_X' FROM CQC OF LOAD 'LEd_X'
CREATE PSEUDO STATIC LOAD 'Ed_Y' FROM CQC OF LOAD 'LEd_Y'
CREATE PSEUDO STATIC LOAD 'Ed_Z' FROM CQC OF LOAD 'LEd_Z'

FORM LOAD 'C1' FROM 'G' 1.0 'Q' 0.5 'Ed_X' 1.0 'Ed_Y' 0.3 'Ed_Z' 0.3
FORM LOAD 'C2' FROM 'G' 1.0 'Q' 0.5 'Ed_X' 1.0 'Ed_Y' 0.3 'Ed_Z' -0.3
FORM LOAD 'C3' FROM 'G' 1.0 'Q' 0.5 'Ed_X' 1.0 'Ed_Y' -0.3 'Ed_Z' 0.3

NONLINEAR EFFECTS
GEOMETRY ALL MEMBERS

MAXIMUM NUMBER OF ITERATIONS 10
NONLINEAR ANALYSIS

Here you are.. Please help me! Thankyou!

RE: Non linear analysis

I do Non-Linear analysis but for static loads and not any spectrum analysis but after you create the loads and make the Form loads, I usually have to issue a Load List command to tell the program what load cases to consider during the analysis. I don't think just because you used the Create command and the Form Load command, the program still has to be told which loads to use for the NLA. Since the Form Load command is doing the loads you want, you might use:
Load List 'C1' 'C2' 'C3'
then you do the NLA command. You can also use Load List All, but that will cause some extra analysis time.

If that does not solve your problem, and you have paid for support, you can contact Intergraph Tech Support and get one of the real experts to find your problem.

_____________________________________
I have been called "A storehouse of worthless information" many times.

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! Already a Member? Login


Resources

White Paper - Understanding Critical Specifications for Dynamic Metrology Applications
Different types of metrology have different critical specifications to consider when determining which actuator technology to use. This white paper goes into detail on the demands of dynamic metrology applications as they apply to the selection of precision linear motion control components and systems. In addition, the relevance of Moore's Law is examined in the context of the industry. Download Now
White Paper - Permanent Non-Welded and Cold Bent Piping Solutions
Commonly used welded piping connections come with skilled labor, validation, inspection, and long commissioning times, as well as the workplace hazards associated with welding. Non-welded permanent mechanically attached fittings offer a viable alternative to welded piping systems that greatly reduces the time to commission piping systems through reductions in many of the time-consuming steps required in welding. Download Now
White Paper - Take Mobile Hydraulic Systems to a New Level
The introduction of digital ecosystems connecting electronic control hardware and software to the Cloud is catalyzing a new era of mobile machine and equipment design innovation. This is enabling OEMs across industries to develop customized solutions that digitally integrate hydraulic and machine controls with the Internet of Things (IoT). Download Now
White Paper - The Evolving Landscape of Commercial Battery-Powered Trucks
What’s driving the evolving landscape of truck electrification? What are the barriers, motivators and strategies for accelerating the electric transition? What insights and resources are available for today’s design engineers working to achieve industry disruption and evolution? For answers to these and other pertinent questions, read this white paper. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close