opensection - Professional Concrete Section Analysis

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✨ Features

• Eurocode-compliant: Full support for EN 1992 (Eurocode 2) for concrete structures
• Fiber-based analysis: Advanced section analysis using fiber discretization
• Material models: Comprehensive constitutive laws for concrete and reinforcing steel
• Interaction diagrams: Generate N-M interaction diagrams for sections
• Flexible geometry: Support for rectangular, circular, T-sections, and custom polygons
• Visualization: Built-in tools for plotting sections and results
• Fast: Optimized NumPy-based computations
• Extensible: Clean API for advanced users and researchers

📦 Installation

From PyPI (recommended)

pip install opensection

From source

git clone https://github.com/Pavlishenku/opensection.git
cd opensection
pip install -e .

Development installation

git clone https://github.com/Pavlishenku/opensection.git
cd opensection
pip install -e ".[dev]"

🚀 Quick Start

import opensection as ops

# Define a rectangular concrete section
section = ops.RectangularSection(width=0.3, height=0.5)

# Define materials (Eurocode 2)
concrete = ops.ConcreteEC2(fck=30)  # C30/37
steel = ops.SteelEC2(fyk=500)       # B500B

# Add reinforcement
rebars = ops.RebarGroup()
rebars.add_rebar(y=0.0, z=-0.20, diameter=0.020, n=3)  # 3Ø20 bottom
rebars.add_rebar(y=0.0, z=0.20, diameter=0.016, n=2)   # 2Ø16 top

# Create solver and analyze
solver = ops.SectionSolver(section, concrete, steel, rebars)
result = solver.solve(N=500, My=0, Mz=100)  # N in kN, M in kN·m

# Check results
print(f"Converged: {result.converged}")
print(f"Max concrete stress: {result.sigma_c_max:.2f} MPa")
print(f"Max steel stress: {result.sigma_s_max:.2f} MPa")

# Verify according to EC2
checks = ops.EC2Verification.check_ULS(result, concrete.fcd, steel.fyd)
print(f"Concrete check: {'OK' if checks['concrete_stress']['ok'] else 'FAIL'}")
print(f"Steel check: {'OK' if checks['steel_stress']['ok'] else 'FAIL'}")

📚 Documentation

Full documentation is available at opensection.readthedocs.io

• User Guide
• API Reference
• Examples
• Theory

💡 Examples

Check out the examples directory for more detailed use cases:

• Basic section analysis
• Interaction diagrams
• Custom sections
• Biaxial bending
• Circular columns
• T-beam design

🛠️ Development

Setting up development environment

# Clone the repository
git clone https://github.com/Pavlishenku/opensection.git
cd opensection

# Create virtual environment
python -m venv venv
source venv/bin/activate  # On Windows: venv\Scripts\activate

# Install development dependencies
pip install -e ".[dev]"

Running tests

# Run all tests
pytest

# Run with coverage
pytest --cov=opensection --cov-report=html

# Run specific test file
pytest tests/test_geometry.py

Code quality

# Format code
black src/ tests/

# Sort imports
isort src/ tests/

# Lint
flake8 src/ tests/

# Type checking
mypy src/

🤝 Contributing

We welcome contributions! Please see CONTRIBUTING.md for details on:

• Code of conduct
• Development process
• Submitting pull requests
• Coding standards
• Testing requirements

📄 License

This project is licensed under the MIT License - see the LICENSE file for details.

🙏 Acknowledgments

• Inspired by the need for open-source structural design tools
• Based on Eurocode 2 (EN 1992-1-1) specifications
• Built with NumPy and Matplotlib

📞 Contact & Support

• Issues: GitHub Issues
• Discussions: GitHub Discussions

🗺️ Roadmap

• Basic section analysis (EC2)
• Interaction diagrams
• Support for ACI 318 (US code)
• Support for GB 50010 (Chinese code)
• Time-dependent effects (creep, shrinkage)
• Crack width calculations
• Deflection analysis
• Web interface
• CAD integration (DXF import/export)

📖 Citation

If you use opensection in academic work, please cite:

@software{opensection2025,
  author = {opensection Contributors},
  title = {opensection: Professional Concrete Section Analysis},
  year = {2025},
  url = {https://github.com/Pavlishenku/opensection},
  version = {1.0.0}
}

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