Title:
Prepublished: Curvilinearity Effect on the Flexural and Shear Strength of Vertically Curved GFRP-Reinforced Concrete Flexural Members
Author(s):
Seyed Mohammad Hosseini, Salaheldin Mousa, Hamdy M. Mohamed, and Brahim Benmokrane
Publication:
Structural Journal
Volume:
Issue:
Appears on pages(s):
Keywords:
critical shear crack theory (CSCT); curvilinear reinforced-concrete (RC) members; design codes; experimental and analytical studies; flexural strength; glass fiber-reinforced polymer (GFRP) bars; modified compression field theory (MCFT); parametric studie
DOI:
10.14359/51745638
Date:
2/11/2025
Abstract:
The geometry of arched (vertically curved) reinforced concrete (RC) members contributes to the development of additional stresses, affecting their flexural and shear strength. This aspect of curvilinear RC members reinforced with GFRP bars has not been reported in the literature. In addition, there are no specific design recommendations that consider the effect of curvilinearity on the flexural and shear strength of curved GFRP-RC members. This study has performed pioneering work in developing models to predict the flexural and shear strength of curvilinear GFRP-RC members with a focus on precast concrete tunnel lining segments. Eleven full-scale curvilinear GFRP-reinforced tunnel segment specimens were tested under bending load as the experimental database. Then, a model was developed for predicting the flexural strength of curvilinear GFRP-RC members. This was followed by the development of two shear-strength prediction models based on the modified compression field theory (MCFT) and critical shear crack theory (CSCT). After comparing the experimental and analytical results, a parametric study was performed to evaluate the effect of different parameters on the flexural and shear strength of curvilinear GFRP-reinforced members. The results indicate that neglecting the curvilinearity effect led to a 17% overestimation of the flexural capacity, while the proposed models could predict the flexural capacity of the specimens accurately. The proposed models based on the MCFT—referred to as the semi-simplified modified compression field theory (SSMFT) and the improved simplified modified compression field theory (ISMCFT)—predicted the shear capacity of the specimens with 28% conservatively. In addition, the modified critical shear crack theory (MCSCT) model was 10% conservative in predicting the shear capacity of curvilinear GFRP-RC members.