Title:
A New Bond Model for RC Beams Strengthened with Embedded Through-Section Method
Author(s):
Sara Mirzabagheri, Andrew Kevin Kenneth Doyle, Amir Mofidi, Omar Chaallal
Publication:
Symposium Paper
Volume:
360
Issue:
Appears on pages(s):
141-155
Keywords:
Bond-Slip, Fracture Mechanics, Embedded Through-Section, FRP Bars, Pull-out Force, Shear Strengthening, Deep Embedment
DOI:
10.14359/51740622
Date:
3/1/2024
Abstract:
Embedded Through-Section (ETS) method is a shear rehabilitation technique for concrete structures involving pre-drilling vertical holes into a reinforced concrete member and installing FRP bars to be bonded using epoxy adhesive. Due to the lack of reliable models for predicting the ETS FRP bond behaviour, developing an accurate model to predict the maximum pull-out force of the ETS technique was deemed a knowledge gap. In this study, the main parameters used in an analytical bond-slip model proposed by the authors were obtained empirically and evaluated against the existing experimental results in the literature. To be able to calculate the maximum pull-out force for ETS FRP bars with different materials, a fracture mechanics-based bond model was defined in terms of the joints' geometrical and material properties, to allow the model to predict the performance of any FRP type with any concrete compressive strength. By using data in the available literature on FRP ETS pull-out tests, statistical analysis was utilized to fit the parameters against experimental data. The proposed model was able to produce superior analytical predictions of the experimental test data when compared to the existing bond models for ETS FRP bars.
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