Effectiveness of ECC for repair of distressed RC beams

Abstract

As the demand for economic infrastructure increases worldwide, there is a greater need to cater for the rehabilitation of concrete structures that are damaged by continuous wear and environmental conditions. Rehabilitation and repair constitutes an important stage in the life cycle of most reinforced concrete and precast structures as it contributes to maintaining serviceability and further extending their operational phase. In this study ECC called Engineered Cementitious Composite which belongs to class of high performance fiber reinforced cement based composite that exhibits strain hardening and multiple cracking behavior under tension and flexure. Several experiments have been performed by researchers to assess the potential use of ECC as a repair mortar using bonded overlay technique. For this purpose seven beams were cast and two beams were loaded to get the ultimate load carrying capacity, then the remaining five beams were stressed to 70 % of the ultimate load. The cracked concrete was removed and surface was prepared to place a layer of overlay mixes having PVA and steel fibers in varying fiber volume fraction and ultimately the repaired overlays were checked for their effectiveness in increasing the capacity of beam under flexural loading and also the bond adequacy was also determined.