Predictive modeling of compressive strength in silica fume–modified RCC using ML under organic acid attack
摘要
The degradation of reinforced cement concrete (RCC) due to organic acids poses critical challenges for infrastructure longevity, particularly in agro-industrial, dairy, and wastewater environments. This study investigates the compressive strength performance of silica fume–modified RCC exposed to citric acid and proposes a machine learning (ML) framework for predictive modeling. A total of six mixes incorporating 0% to 15% silica fume were experimentally evaluated for compressive strength at 7, 28, and 56 days. Post-curing, samples were exposed to citric acid concentrations ranging from 0% to 10% to simulate organic degradation. Experimental results showed that 10% silica fume significantly enhanced strength and acid resistance. A synthetic dataset (n = 1000) was generated using controlled domain-informed sampling across seven input variables. Five ML models—Support Vector Regression, Decision Tree, Extra Trees, Random Forest, and XGBoost—were trained and validated using R², RMSE, MAE, MAPE, a20, and IOA. XGBoost achieved the highest performance (R² = 0.9782; MAPE = 2.81%). SHAP and PDP interpretability techniques identified curing age, silica fume content, and acid concentration as critical features. The proposed model demonstrates strong predictive accuracy and robustness, offering a reliable tool for optimizing RCC design in acid-exposed environments.