Updated 2022-11-28

The Open System for Earthquake Engineering Simulation (OpenSees)

Overview

  • OpenSees is a software framework for simulating the seismic response of structural and geotechnical systems.
  • The goal of Opensees development is to improve the modeling and computational simulation in earthquake engineering
  • The software has advanced capabilities for modeling and analyzing the nonlinear response of systems using a wide range of material models, elements, and solution algorithms
    • Modeling: OpenSees provides beam-column and continuum elements for structureal and geotechnical models, and contains a wide range of uniaxial materials and section models for beam-columns
    • Analysis: OpenSees provides nonlinear static and dynamic methods, equation solvers, and methods for handling constraints.

Running OpenSees

  • Prior to loading the OpenSees module, you will also need the Intel 17.0 compiler: module load intel/17.0 opensees/3.0.3
  • Example TCL scripts can be located at ${OPENSEESROOT}/OpenSees/EXAMPLES/.

Tip

Any examples that you wish to utilize should be copied to your user directories; for example, type
cp -r ${OPENSEESROOT}/OpenSees/EXAMPLES/Truss.tcl ~/data

  • Running an OpenSees script is as simple as typing OpenSees MyScript.tcl

Note

The current build of OpenSees available through the modules does not support MPI

Example of How to Use OpenSees

  • The following example highlights a basic example for running an interactive OpenSees session on inferno:
salloc -I -X -q inferno -N ntasks-per-node=1 --time=00:05:00 --mem=128G
module load intel/17.0 opensees/3.0.3
cp -r ${OPENSEESROOT}/OpenSees/EXAMPLES/Truss.tcl ~/data
cd data/
OpenSees Truss.tcl
  • If successful, the following output should be displayed on the screen:
         OpenSees -- Open System For Earthquake Engineering Simulation
                 Pacific Earthquake Engineering Research Center
                        Version 3.0.3 32-Bit

      (c) Copyright 1999-2016 The Regents of the University of California
                              All Rights Reserved
  (Copyright and Disclaimer @ http://www.berkeley.edu/OpenSees/copyright.html)

node 4 displacement:              0.53009277713228375450            -0.17789363846931777191

 Node: 4
    Coordinates  : 72 96
    Disps: 0.530093 -0.177894
    Velocities   : 0 0
     unbalanced Load: 100 -50
    ID : 0 1

Element: 1 type: Truss  iNode: 1 jNode: 4 Area: 10 Mass/Length: 0 cMass: 0
     strain: 0.00146451 axial load: 43.9352
     unbalanced load: -26.3611 -35.1482 26.3611 35.1482
      Material:
Element: 2 type: Truss  iNode: 2 jNode: 4 Area: 5 Mass/Length: 0 cMass: 0
     strain: -0.00383642 axial load: -57.5463
     unbalanced load: -34.5278 46.0371 34.5278 -46.0371
      Material:
Element: 3 type: Truss  iNode: 3 jNode: 4 Area: 5 Mass/Length: 0 cMass: 0
     strain: -0.00368743 axial load: -55.3114
     unbalanced load: -39.1111 39.1111 39.1111 -39.1111
      Material:

Further Reading