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

Abstract

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.

Shear strengthening of RC beams with NSM FRP. I: Review of strength models

“…The theoretical basis and core idea of these models are summarized and discussed. In the companion paper (Ke et al, 2022a), the performance of these models will be assessed using a large experimental database including 196 RC beams shear strengthened with NSM FRPs selected from the existing literature by the authors.…”

“…Against the above background, this paper and the companion paper (Ke et al, 2022a) respectively present a comprehensive review and an assessment of the existing strength models for NSM FRP shear strengthened beams. In this paper, all the available strength models are summarized and classified into three categories based on their used approaches.…”

“…In this paper, all the available strength models are summarized and classified into three categories based on their used approaches. This paper not only aims to bring a deep understanding of these models but also provides a basis for the assessment in the companion paper (Ke et al, 2022a).…”

“…Based on the existing NSM FRP-concrete interfacial bond-slip relationships, some numerical studies have been developed respectively for beams strengthened with NSM FRPs in flexure (e.g. Hawileh 2012; Ke et al, 2022; Omran and El-Hacha 2012; Sakar et al, 2014; Zhang and Teng 2014; Yao and Wu 2016; Zhang and Yu 2016; Zhang and Teng 2013) and shear (e.g. Abdel-Jaber et al, 2021; Almassri et al, 2015; Barros et al, 2013; Haddad and Obaidat 2018; Jawdhari and Adheem 2018; Mostofinejad et al, 2019) to simulate the behaviours of strengthened beams in debonding failure modes.…”

Predicting Shear Capacity of RC Beams Strengthened with NSM FRP Using Neural Networks

“…Formulation of design equations' by Perera (2014)16] and 'Shear strengthening of RC beams with NSM FRP. II: Assessment of strength models' by [17].…”