Data, Code and Design Software for: Buckling Stability, FEA Validation, and Simplified Design Equations for Stepped FRP Composite Columns via Machine Learning

Data, source code and a stand-alone design application accompanying the article "Buckling Stability, FEA Validation, and Simplified Design Equations for Stepped FRP Composite Columns via Machine Learning". Contents: - results/: database of 10,000 stepped FRP-confined columns (exact critical loads and finite element checks); 1,200 nonlinear ultimate-load analyses; machine-learning results (ANN, RF, GBR) for the critical and ultimate loads; design-equation and column-curve coefficients; validation data from published tests; jacket-material and sensitivity studies (CSV/JSON). - code/: Python scripts that reproduce every number, table and figure of the article (exact solution, Euler-Bernoulli and Timoshenko finite element models, nonlinear fibre model, machine learning, design equations). - calculator/StepCol-Designer.exe: Windows application for the critical load, the equivalent effective length factor K_eq and the ultimate load of two-segment stepped FRP-confined columns. - figures/: figures of the article, graphical abstract and screenshots of the application. Licences: code under MIT; data and figures under CC BY 4.0.