A data-enhanced simplified RA-STM for shear strength estimation of FRP-RC deep beams
摘要
In recent years, the shear strength of fiber-reinforced polymer (FRP) reinforced concrete (RC) beams has been increasingly well documented, as these beams are more susceptible to shear failure than conventional steel-RC beams. This study focuses on developing a rational mechanism-based model for predicting the shear capacity of FRP-RC deep beams without stirrups. A rotating angle-softened truss model (RA-STM) with an appropriate tension-stiffening relationship is employed as the base model. The predictive performance of the base RA-STM is validated against 177 experimental datasets gathered from existing literature. The analytical data derived from the base RA-STM are subsequently used to improve performance via a data-driven approach. Consequently, a failure mode classification index is developed to classify the failure mechanisms of deep FRP-reinforced beams without transverse reinforcement, and explicit functions for equilibrium and compatibility conditions are formulated. Two simplified versions of the base RA-STM (RA-STM_I and RA-STM_II) are established which provides better predictions than several other mechanical-based models. Furthermore, the simplified RA-STM_II effectively reflects the impact of three governing parameters a/d ratio, ρfEf, and fcm on the shear strength.