Data-driven multi-objective optimization of recycled aggregate concrete mixes via LightGBM strength modelling and SHAP interpretability
摘要
This paper presents a data-driven framework for predicting the compressive strength of recycled aggregate concrete (RAC) under design constraints, an environmentally sustainable construction material. The proposed method uses a LightGBM regression model integrated with multi-objective optimisation via the NSGA-II algorithm, improving prediction accuracy, robustness, and interpretability. While LightGBM is compared against XGBoost, CatBoost, and a stacking-based ensemble for benchmarking purposes, all reported results, including optimisation, uncertainty analysis, and SHAP-based feature importance, correspond exclusively to the final LightGBM-based model, ensuring clarity and consistency. A tolerance-based accuracy criterion of