Analytical Solutions for the Flexural Behavior of Metal Beams Strengthened with Prestressed Unbonded CFRP Plates

Document Type : Research Papers


1 Arizona State University, School of Sustainable Engineering and the Built Environment, Tempe AZ 85287, USA

2 Empa, Swiss Federal Laboratories for Materials Science and Technology, Structural Engineering Research Laboratory, Dübendorf, Switzerland

3 University of Tehran, School of Civil Engineering, Tehran, Iran


Trapezoidal prestressed unbonded retrofit (TPUR) systems have been recently developed and tested. The authors have already developed a comprehensive and accurate analytical solution for the TPUR system that takes many system parameters into account. The main aim of this paper is to develop a simplified analytical solution for predicting the behavior of metal beams that have been strengthened with the TPUR system. The developed analysis method can be useful to engineers because of its simplicity. An energy approach based on Castigliano’s theorems is used to study the flexural behavior of a steel beam retrofitted with the TPUR system. A parametric study was performed and the comparative results showed that the results using Castigliano’s first theorem are in agreement with the results using the flexibility approach.


Main Subjects

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