Critical Shear Crack Theory in Evaluating the Behavior of Reinforced Concrete Flat Slabs Strengthened with FRP Composites

Authors

1 School of Civil Engineering, College of Engineering, University of Tehran, Tehran 1417613131, Iran

2 Department of Civil Engineering, Isfahan University of Technology, Isfahan 8415683111, Iran

Abstract

Flat slabs are an efficient and economical solution for floor systems subjected to relatively light loads. However, due to the absence of beams at slab-column connections, these slabs may face punching shear failure, especially under unbalanced moments. In some cases, failure may occur in a flexural mode, depending on the reinforcement configuration and loading conditions. Alongside load-bearing capacity, predicting the failure mode is vital in the design process. Despite numerous studies on the load-bearing capacity and failure mechanisms of flat slabs, the application of the Critical Shear Crack Theory (CSCT) to FRP-strengthened slabs has received limited attention. This study investigates the effectiveness of CSCT in predicting the failure behavior of flat slabs externally strengthened with FRP strips using EBR and EBROG techniques.

Keywords

Main Subjects

References

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Journal of Civil and Environmental Engineering
Volume 56, Issue 123 - Serial Number 123
Summer 2026
September 2026
Pages 75-87

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