Textile-reinforced mortar external strengthening of corroded reinforced concrete beams

Abstract

The need for reliable material techniques for the restoration of corrosion-damaged reinforced concrete (RC) elements cannot be over-emphasised, especially when considering the sustainability aspects of reinforced concrete structures. This investigation examines the application of basalt textile-reinforced mortar for external strengthening of corroded RC beams in flexure. In that regard, a set of reinforced concrete beams subjected to accelerated corrosion to 10% and 20% mass loss of the main steel bars at mid-span and were strengthened using TRM. In total, 7 beams were tested under four-point bending for the following conditions: 1 control, 2 corroded and 4 strengthened. Two strengthening schemes were single ply TRM of equivalent surface area. The results show that corrosion had detrimental effects on load-carrying capacity, yield strength, as well as ductility of corroded beams. Strengthening schemes restored the load capacity of the 10% corroded beams within a range of 105% to 112% of control load capacity. Recovery of the load carrying capacity was not achieved for the 20% corroded beams. All the strengthened specimens ultimately failed by fibre reinforcement rupture, thus indicating full utilisation of composite action of the TRM.