Steady state response

Forum for OpenSees users to post questions, comments, etc. on the use of the OpenSees interpreter, OpenSees.exe

Moderators: silvia, selimgunay, Moderators

Post Reply
berktaftali
Posts: 68
Joined: Fri Jul 02, 2004 6:10 am
Location: Computers and Structures, Inc.

Steady state response

Post by berktaftali »

I'm trying the get the residual displacements in a structure after I run a nonlinear time history analysis.

The deformations Just after the ground motion ends are not the ones I'm looking for, since the structure starts free vibration with initial conditions and comes to a steady state after a while. I need to get the displacements after the structure reaches steady state.

I was letting the analysis run for 1.5 times the original length of the ground motion in the free vibration phase to get the residuals, which proved to be a very inefficient way (2.5 x analysis duration & output files).

To summarize, I need to find a way to the same thing that DRAIN2-DX command "*REST"" does, i.e. brings the structure to a static equilibrium state after a dynamic analysis.

Any ideas?
Berk Taftali
Georgia Institute of Technology
Ph.D. Candidate, Structural Engineering, Mechanics, and Materials
School of Civil and Environmental Engineering
Atlanta, GA 30332 USA
Email: gte994y@mail.gatech.edu
denizutkutug
Posts: 4
Joined: Tue Sep 07, 2004 12:21 am
Location: Ankara - TURKEY
Contact:

Post by denizutkutug »

Hi,
Are you using raw or modified record with baseline correction? For, integration of the complete raw-time series may not result zero; leading to continuing velocity or residual displacements.
Best regards.
Res. Asst. Deniz Utkutug
dutkutug@metu.edu.tr

Middle East Technical University
Civil Engineering Department
Ankara, TURKEY
Post Reply