×
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

Muiltilinear-Plastic (Kinematic) Link Through OAPI (Excel)

Muiltilinear-Plastic (Kinematic) Link Through OAPI (Excel)

Muiltilinear-Plastic (Kinematic) Link Through OAPI (Excel)

(OP)
Hello all,

I am trying to create a model for a Wharf where the Axial Load-Displacement relationship of the Steel Piles is defines using a Multilinear Plastic (Kinematic) Link. The Load-Displacement relationships I have found through Non-linear Buckling Analysis of the piles.

We have 140 Piles and 140 Load-Displacement relationships in an Excel file, so we want to input them using the OAPI. All the piles show a softening behavior or 'negative slope' after peak load, which is of some concern to us. However, I have done a simulation manually entering the following Load-Displacement Relationship, and the program accepted it and provided good results. Here the P vs. D information:

D (in) P (kip)
-5.00 -20.66
-0.75 -20.66
-0.10 -43.36
-0.09 -46.89
0.00 0.00
0.01 4.00
0.75 5.00

The first two values indicate a 'remaining capacity' of the pile after buckling of 20.66 kips. The capacity of the pile in compression is 46.89 kips. Since we don't have information for the behavior in tension, we just input some nominal values for the positive deformation branch.

If I input this non-linear relationship for the multilinear link manually, the program accepts it and runs without problems.

However, if I input it through the OAPI, it creates the multilinear link property and assigns it successfully, but it just gives the default Load-Displacement relationship.

I know the code is working because if I use a Load-Displacement relationship like the ones in the verification examples, say:

D (in) P (kip)
-16 -55
-6 -50
-1 -40
0 0
2 50
6 70
16 80

...my code is able to correctly input the Load-Displacement relationship. Note that there are no negative slopes here.

Now, I am sorry for the long-winded description of my problem, but it would be most helpful to hear your impressions on this, ideas on why the OAPI would have problems inputting the same values that I am able to input manually, or alternatives to my general approach.

***As an aside, does anyone know what type of code goes into the "order rows" button in the multilinear plastic link nonlinear relationship section, and how to implement it through the OAPI? I feel this might be helpful as well.

Again, I am most thankful and look forward to hearing from you.

Kind regards,

Oswaldo Russian

RE: Muiltilinear-Plastic (Kinematic) Link Through OAPI (Excel)

Hello,
Before any comment i think i need to know what code have you wrote. The most common error in api is the range of the arrays. For example there are 5 elements in array but array defined as 4 or 6 elements, sap just skip it.

***I defined an interaction diagram to sap2000 by api before and I ordered rows in Excel with an another macro.


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