Mechanism-aware physics-guided XGBoost model for shear strength prediction of FRP-strengthened RC beams
摘要
Shear strengthening of existing reinforced concrete beams via externally bonded fiber-reinforced polymer (FRP) systems is widely practiced; however, accurate prediction of shear capacity remains challenging due to complex interaction mechanisms, regime-dependent failure behavior, and the limited generalization of existing design-code equations. Code-based models calibrated on restricted experimental data often exhibit bias and large scatter across varying geometries, shear span-depth ratios, and FRP layouts, whereas purely data-driven machine-learning approaches typically lack physical interpretability. To address these limitations, a mechanism-aware physics-guided machine-learning framework is proposed for predicting the shear strength of FRP-strengthened reinforced concrete beams. The framework decomposes total shear resistance into a mechanics-based concrete contribution and a data-driven residual component modeled via XGBoost, enabling variance reduction and physically informed learning. A compiled database of 275 experimental beam tests is classified into low