ONSAS.m: an Open Nonlinear Structural Analysis Solver for GNU-Octave/Matlab

Table of Contents

1. About ONSAS
2. For users
3. Contributions
4. Contact

About ONSAS

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What is ONSAS?

ONSAS is a GNU-Octave code for static/dynamic and linear/non-linear analysis of structures. The first version was developed for educational purposes and was published in a handbook of the course Análisis no lineal de Estructuras taught at Facultad de Ingeniería, Universidad de la República.

What can ONSAS be used for?

The current version allows to perform dynamic/static nonlinear analyses of beam/truss/solid 3D structures. A reduced list of features is listed at next:

• Elements 2-node truss, 2-node Bernoulli frame, 4-node tetrahedron.
• Static analysis methods Newton-Raphson Method and Cylindrical Arc-Length Method.
• Dynamic analysis methods Newmark Method and α-HHT method.
• Loads nodal loads, time-history user-defined loading program.

Some examples

A wind turbine model

A truss tower model

A chain model

License

The code is distributed under a GNU-GPL 3.0 license.

How to use ONSAS

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The user should follow these steps to install and run onsas:

1. Download and install GNU-Octave and Paraview
2. Download the ONSAS zip source files from the realeases web https://github.com/ONSAS/ONSAS/releases
3. Open GNU-Octave, move to the examples directory and run one of the examples.

Contributions

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Authors of code

The following authors collaborated in various tasks including: design, development and testing of the code, with specific contributions given by the commits history: Jorge M. Pérez Zerpa ¹, J. Bruno Bazzano^1,2, Joaquín Viera ¹, Mauricio Vanzulli ³ and Marcelo Forets⁴.

The following authors contributed with specific functions of files, of great relevance for the code: Jean-Marc Battini⁵ (contributed functions related to the computation of static internal forces of the nonlinear frame element) and Sebastian Toro⁶ , provided the functions: f_LectDxf.m, f_ValGrCode.m and f_XData.m, used in the dxf import function.

Affiliations:

1. Instituto de Estructuras y Transporte, Facultad de Ingeniería, Universidad de la República, Montevideo, Uruguay
2. Bazzano & Scelza Ingenieros, Montevideo, Uruguay
3. Instituto de Ingeniería Mecánica y Producción Industrial, Facultad de Ingeniería, Universidad de la República, Montevideo, Uruguay.
4. Departamento de Matemática y Aplicaciones, Centro Universitario Regional del Este, Universidad de la República, Maldonado, Uruguay
5. Department of Civil and Architectural Engineering, KTH Royal Institute of Technology, Stockholm, Sweden
6. CIMEC Santa Fe, Argentina

Contributions and Acknowledgments

The complete list of contributions and acknowledgments is available at the documentation site.

Contact

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If you have any question you can send an e-mail to jorgepz[AT]fing.edu.uy or .