Development of a CatBoost-Based Predictive Model for Estimating the Compressive Strength of Waste Plastic-Doped Concrete
摘要
This study presents a CatBoost regression model to predict the compressive strength of concrete doped with waste plastic. Input variables included % plastic waste (0–10%), % fly ash (0–10%), and curing days (3–90). The model achieved near-perfect training performance (R2 = 1.0, RMSE = 0.0003 MPa) but showed reduced accuracy on the test set (R2 = 0.762, RMSE = 4.03 MPa), indicating overfitting. Analysis revealed that increasing plastic waste reduces strength, especially beyond 4–6%, while adding 10% fly ash consistently improves strength, peaking at 41.72 MPa after 90 days. SHAP analysis confirmed % plastic waste and curing days as the dominant predictors. The model offers an effective and interpretable tool for designing sustainable concrete mixes that balance environmental and mechanical performance.