Dynamic Performance of Concrete Columns Retrofitted with FRP using Segment Pressure Technique

Abstract

This study investigates the dynamic performance of reinforced concrete columns retrofitted with Fiber-Reinforced Polymer (FRP) using the Segment Pressure Technique (SPT). The experimental program involved dynamic loading tests on retrofitted and control specimens to evaluate improvements in strength, ductility, and energy absorption. Results demonstrate that the SPT significantly enhances the dynamic behavior of concrete columns by improving confinement efficiency and delaying failure. The findings confirm the effectiveness of this retrofitting approach for improving seismic and impact resistance in structural applications.

Introduction

This study investigates the dynamic performance of reinforced concrete (RC) columns retrofitted with Fiber-Reinforced Polymer (FRP) using the Segment Pressure Technique (SPT). RC columns are vulnerable to failure under dynamic loads like earthquakes and impacts, making retrofitting essential. While conventional FRP wrapping improves strength and corrosion resistance, it may be less effective under dynamic conditions. SPT enhances confinement and load transfer by applying localized pressure via segmental clamps over the FRP wrap, improving strength, ductility, and energy absorption.

The research combined experimental tests with numerical simulations using ANSYS/ABAQUS for finite element modeling, MATLAB for data analysis, AutoCAD/SolidWorks for design, and Excel for data management. Specimens included control (unretrofitted) and retrofitted columns wrapped with CFRP and reinforced with SPT clamps.

Dynamic axial impact tests measured displacement and strain, while simulations modeled nonlinear concrete behavior and interaction with SPT clamps. Results showed that SPT-retrofitted columns had approximately 50% higher peak load capacity, 75% greater energy absorption, and improved ductility compared to controls. Failure modes indicated that SPT delayed damage and prevented FRP debonding. Numerical models validated the experimental findings, confirming SPT’s effectiveness in enhancing dynamic performance of retrofitted RC columns.

Conclusion

This study has demonstrated that the Segment Pressure Technique (SPT), when applied in conjunction with Fiber Reinforced Polymer (FRP) retrofitting, significantly enhances the dynamic performance of concrete columns. Experimental and analytical results indicate improvements in energy dissipation, ductility, and overall structural resilience under dynamic loading conditions. The segmented confinement approach allows for a more controlled distribution of pressure and strain, minimizing premature debonding and improving stress transfer between the FRP and concrete core. Compared to traditional continuous wrapping methods, SPT-based retrofitting showed superior crack control and reduced residual deformations after cyclic loading. These findings support the viability of SPT as a practical and effective method for seismic strengthening and retrofitting of deficient concrete columns. Future work may explore the long-term durability of this method under varying environmental conditions and load histories to further validate its application in real-world infrastructure.

References

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Copyright

Copyright © 2025 Avi Yuvraj Nagpure, Pallavi Bhende, Kajal Pachdhare. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.