Shear strengthening of RC beams with NSM FRP. II: Assessment of strength models

The application of near-surface mounted (NSM) fiber-reinforced polymer (FRP) for shear strengthening of RC beams has attracted abundant research in the past few decades, and a number of strength models for predicting the contribution of NSM FRPs to the shear capacity of strengthened beam have been proposed. In the first of these two companion papers, a total of 12 strength models of NSM FRP shear strengthened RC beams collected from the existing literature have been comprehensively reviewed, while the present paper aims to provide an objective assessment of these models. To this end, the experimental results of 196 RC beams strengthened in shear with NSM FRP bars/strips are collected from the existing literature, as the database for the assessment. The comparisons between the experimental results and predictions by these strength models reveal that the existing strength models all fail to give accurate predictions. The reasons for the inaccurate predictions of these models are also analyzed.