AI for Sustainable Concrete: Hybridization of ML model

In this study, we use Hybridized Machine Learning (ML) algorithms for prediction of CS of fly-ash based Geopolymer Concrete (GPC). The base models include Extreme Gradient Boosting (XGB) and Random Forest (RF). The hybridization involves using metaheuristic optimization algorithms (like Particle Swarm Optimization - PSO and Grey Wolf Optimization - GWO) to tune the models’ hyperparameters.

Model performance was evaluated using statistical indices and sensitivity analysis. The findings showed that the PSO-XGBoost model outperformed other models with accuracy of R2 and RMSE of 0.97 and 3.85 MPa respectively. The ranking of the ML models obtained was: PSO-XGBoost > GWO-Random Forest > GWO-SVR for both train and test set. SHAP analysis identified Curing Temperature and Curing Time as the most critical parameters effecting CS.

Overall Procedure for Hybridized ML Model Development

SHAP Importance Plot for GPC Compressive Strength

Hybridized ML Model Performance Comparison (R² & RMSE)