Published Paper Details:

The repair and strengthening of existing reinforced concrete (RC) structures continue to gain significance as global environments deteriorate and infrastructure ages while the demands of service increase. Traditional strengthening techniques such as steel jacketing and the incorporation of synthetic fiber-reinforced polymer (FRP) systems are useful and broadly accepted methods of strengthening concrete yet can gaps or weaknesses of their own by adding unnecessary weight, contrived corrosion issues, or high environmental costs. There is an increasing effort in research towards using natural fibers--such as jute, basalt, and sisal--as sustainable alternatives to synthetic fibers in FRP applications. Natural fiber-reinforced polymers (NFRPs) provide advantages including biodegradability, renewability, cost, and desirable mechanical properties. Presented here is a thorough literature review, of recent work identifying advances in natural and hybrid fiber composites that were utilized in strengthening concrete elements. The reviewed works had various techniques employed such as full wrapping (encapsulation) and strip wrapping of columns, beams, and piles, as well as the use of textile-reinforced mortars (TRMs) that combined both natural and synthetic fibers. The reviewed works consistently showed improvements in the compressive, flexural, and shear capacities of the concrete elements, improvements in ductility and energy absorption were also seen in all works covered. Additional proof that the durability of the systems held up in heavy environmental conditions such as the acidic, alkaline, marine, and potable water conditions were also validated. The hybrid options (untarred configurations) of most of the studies that were used as natural fiber combinations stood out in their performance.