Analytical Study of Fatigue Crack Growth Behavior of Steel Structure Reinforced with FRP

Document Type : Original Article


1 SJB Institute of Technology

2 Kengari Dr Vishnuvardhan Rd, 5th Block, Phase 3, Banashankari, Bengaluru, Karnataka, India



The using up of fiber reinforced polymer (FRP) in retrofit and repair in industrial fields is extremely efficient and also capable in increasing service life cycle of the structures. In this paper the investigation on the FRP repairing on crack surface of S235 steel plate which is subjected to tension loading has been carried out. The variation in stress intensity factor (SI) around the crack on the surface of steel plate, is analytically investigated and crack growth rate for steel plate was estimated by considering the stress intensity factor value in the Paris-Erdogan equation. Results recommended that laminate made of carbon fiber reinforced polymer (CFRP) repaired on the crack surface is the most effective one   which showed decreased stress intensity value of 328.9Mpa.mm0.5, whereas the unreinforced steel plate with SIF value 389.29Mpa.mm0.5. Compare to the glass FRP with high elasticity modulus, it showed decrease in SIF value 326.95Mpa.mm0.5, results showed that 15-20% reduction in stress intensity (SI) factor when it compares with bare steel plate and with FRP reinforced plate. Finally results showed that reinforcement of FRP on the cracked surface of the steel structure yield good results as increasing its fatigue life by decreasing the expansion of crack at its tip.


Main Subjects

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  • Receive Date: 14 July 2022
  • Revise Date: 02 November 2022
  • Accept Date: 26 December 2022
  • First Publish Date: 26 December 2022