Innovative Repair of Severely Corroded T-Beams Using Fabric-Reinforced Cementitious Matrix

Abstract

This paper offers an innovative technique for rehabilitation of severely corroded reinforced concrete (RC) T-beams using fabric-reinforced cementitious matrix (FRCM). Eight RC T-beam specimens were constructed and tested to failure under four-point load configuration. One beam was neither corroded nor repaired to act as a benchmark. Seven beams were presubjected to accelerated corrosion for 5 months that corresponded to an average tensile steel mass loss of 22%. Corrosion was restricted to the tensile steel located in the middle third of the beam span. Six corroded beams were repaired with either carbon or basalt FRCM system whereas one corroded beam was left unrepaired. The fabrics were internally embedded within the clear cover of the corroded-repaired region and/or externally bonded along the beam span. Corrosion damage significantly reduced the flexural capacity and ductility of the unrepaired beam. The basalt FRCM system could not restore the original flexural capacity of the beam whereas the carbon FRCM system fully restored the capacity. Doubling the amount of the internally embedded carbon FRCM layers slightly increased the strength gain but restored only 90% of the original beam ductility. The use of a combination of internally embedded and externally bonded carbon FRCM layers was more effective in improving the flexural response than the use of same amount of FRCM layers internally embedded within the corroded-repaired region.