FStr – Finite Strip Computer Application

Elastic Buckling Analysis of Thin-Walled Structures

🌐 Website 1: fstr.coc.ufrj.br

🌐 Website 2: GitHub Pages

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🧠 What is FStr?

FStr is a MATLAB-based application designed for elastic buckling analysis of thin-walled structural members using the Finite Strip Method (FSM). It offers an intuitive interface to perform simulations and visualize buckling modes in both 2D and 3D. The user can:

• Compute critical buckling loads and their corresponding member lengths;
• Visualize colorful 3D buckling mode shapes;
• Generate signature curves for comprehensive structural analysis.

Key Features

• Uses trigonometric series in the longitudinal direction to interpolate internal solutions and accommodate diverse boundary conditions;
• Signature curve generation across a range of member lengths;
• Color-enhanced 3D buckling mode visualization;
• Developed with MATLAB App Designer, ensuring a clean and accessible GUI for research and engineering use.

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🖥️ Installing the Standalone Windows (.EXE) Version

To install the standalone version of FStr on Windows:

1. Download the latest .exe file from the Releases section;
2. Run the installer and follow the instructions;
3. Install the MATLAB Runtime when prompted;
4. A desktop shortcut will be created;
5. Launch the application to start analyzing structures.

Notes:

• To uninstall, remove both “FStr” and “MATLAB Runtime” via system settings;
• If the program does not run properly, reinstall the MATLAB Runtime;
• Conflicts may arise with other applications requiring MATLAB Runtime;
• For bug reports, contact Joao Alfredo De Lazzari ([email protected]).

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🔧 Installing the MATLAB App (.mlappinstall) Version

To install the FStr App in MATLAB:

1. Download the latest .mlappinstall file from the Releases section;
2. Open MATLAB 2017b or newer (earlier versions may also work);
3. Navigate to the "APPS" tab;
4. Click "Install App";
5. Select the .mlappinstall file and choose "Install", "Update", or "Re-install".

The app will appear in your MATLAB Apps list. To uninstall, right-click the app icon and select "Uninstall".

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👨‍💻 Developers

Joao Alfredo De Lazzari

Eduardo de Miranda Batista

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🔖 Official Registration

This software, titled Finite Strip Computer Application (FStr), is officially registered with the Brazilian National Institute of Industrial Property (INPI). The software is free to use, but internal routines are proprietary and legally protected.

➡️ For full details, see the SOFTWARE_REGISTRATION.md file.

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🔗 Related Links

• LabEST – Laboratory of Structures and Materials, UFRJ
• COPPE – Graduate Institute of Engineering, UFRJ
• PEC – Civil Engineering Program, UFRJ
• IST – Instituto Superior Técnico, ULisboa
• CERIS – Civil Engineering Research and Innovation for Sustainability
• CORE Group – Composites Research Group, IST

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📧 For inquiries or technical support, please contact Joao Alfredo De Lazzari at [email protected].