Reinforced concrete beams repaired and strengthened in flexure and shear with the use of textile reinforced mortars (TRM's)

In the aftermath of moderate or severe earthquakes, reinforced concrete beams suffer from failures, mainly related to high axial and shear forces. A new promising technique used for the enhancement of the flexural and shear capacity of reinforced concrete elements is the use of fibers in the form of textiles embedded in cementitious matrices. In the present study initial results from an experimental and analytical work will be presented. The programme involves two groups of reinforced concrete beams tested up-to failure and subsequently repaired and strengthened with the use of TRMs. The parameters used in the programme was the amount of the external reinforcement ρf, the shear span-to-depth ratio and the amount of reinforcing steel ρs. The results will be used for comparison with those obtained from a strut-and-tie model analysis. At the same time calibration of the existing equations for the modes of failure and the bond behaviour of the TRMs was implemented. From the results the efficiency of the TRMs was evident, since most of the initial strength and stiffness of the beams was regained. At the same time good correlation between the experimental and the analytical data was identified.