Title:
Evaluation of KDS 14 Draft Model for One-Way Shear Strength of Slender Concrete Members Reinforced with Fiber-Reinforced Polymer (FRP) Rebars
Author(s):
Ngoc Hieu Dinh, Si-Hyun Kim, Kyoung-Kyu Choi
Publication:
IJCSM
Volume:
19
Issue:
Appears on pages(s):
Keywords:
Fiber-reinforced polymer, One-way shear strength, Design codes, RC beams, Compression zone
DOI:
10.1186/s40069-025-00804-1
Date:
11/30/2025
Abstract:
Currently, the evaluation methods and design codes for predicting the shear strength of FRP-RC members are being continuously developed and updated. The revision draft of the Korean Standard KDS 14 20 22 (KDS 14 draft) adopts the compression zone failure mechanism theory to predict the one-way shear strength of slender steel-reinforced concrete members. This study extends the application of the KDS 14 draft model to slender concrete members reinforced with fiber-reinforced polymer (FRP) rebars. The model performance was evaluated using a comprehensive database of slender FRP-reinforced concrete (RC) specimens, including 304 and 110 specimens without and with FRP stirrups, respectively. The strength prediction of the KDS 14 draft model was compared with those of the existing state-of-the-art international design guidelines and of other recently developed models for FRP-RC members. The KDS 14 draft model demonstrated promising performance over a wide range of design parameters, exhibiting the lowest scatteredness among the evaluated methods. It exhibited a strong correlation with the dataset while maintaining an acceptable level of safety and reliability. Among the investigated design models, the ACI 440.11-22 design method exhibited the highest scatteredness and conservatism for specimens without FRP stirrups. However, the JSCE model provided overly conservative predictions for specimens with FRP stirrups because of the rigorous adoption of a strain limit for FRP stirrups. In addition, parametric analyses were conducted, and design examples were presented to further understand the influence of key design parameters and the applicability of the KDS 14 draft model for FRP-RC beams.