Experimental Study on Strengthening of Damaged Steel Flexural Members Using CFRP Composite Wraps

Most of the structures constructed worldwide, after three or four decades of service, require strengthening for lack of stiffness, strength, durability or ductility for improved performance and better serviceability for the remaining period of their intended life span. Since fiber-reinforced polymer (FRP) composites are lighter in weight and easy to apply at critical locations of concrete/steel structures, they are preferable in restoring/rehabilitating of structures after undergoing damage/deterioration. The overall cost incurred on strengthening of members using FRP composites is found to be minimum compared to complete replacement of damaged structural components. This paper presents the experimental study on the use of FRP composites for strengthening of damaged steel flexural members. Some of the situations where strengthening of steel structural members is required are inadequate design, last minute changes in design, revised loading requirements, unexpected/accidental damages, deterioration due to change in environmental conditions, revised code requirements, etc. The test results obtained showed that the failed steel beam specimens wrapped with carbon fiber-reinforced polymer (CFRP) sheets and reinforced with CFRP strips tend to exhibit higher strength characteristics than the conventional steel beam specimens.