For the investigation of fatigue damage behavior of textile reinforced concrete (TRC)-strengthened RC beams, in this study, eight RC beams were fabricated, and five of them were strengthened with TRC and tested under fatigue loading until failure, using a four-point bending setup. Research parameters included reinforcement ratio, textile ratio, and strengthening methods (single-side and U-wrapped). The failure mode, fatigue life, fatigue deformation, and other properties of TRC-strengthened beams were analyzed. Experimental results revealed that there were two fatigue failure modes for TRC-strengthened RC beams. In the first mode, the textile was snapped, but the steel bars did not rupture. In the second mode, both the textile and steel bars broke. Fatigue failure modes depended on the textile ratio. The TRC-strengthened beam’s fatigue life was significantly higher than the non-strengthened RC beam. At the same textile ratio, the TRC-strengthened beam’s fatigue life using the single-side method was longer than that using the U-wrapped method. With the increase in fatigue loading time, the midspan deflection of the TRC-strengthened beam was developed in three stages, namely rapid development stage, stable development stage, and destabilized development stage. The residual deflection and strain damage accumulation of tensile steel bars of TRC-strengthened beams were significantly reduced with the increase in textile or reinforcement ratios; thus, the beam’s fatigue life was prolonged.

The flexural behavior of corroded reinforced concrete (RC) beams strengthened with textile reinforced concrete (TRC) was analyzed and discussed in this work. Thirteen beams, including one reference beam, three corrosion-only beams, and nine TRC-strengthened corroded beams, were tested under four-point bending. The failure modes, cracks, bearing capacity, load–displacement curves and ductility of the tested beams were analyzed. The results showed that the TRC played a role in increasing the number of cracks and decreasing the width of the cracks in the corroded RC beams. In terms of improving the bearing capacity, TRC can improve the bearing capacity of corroded beams even more than the reference beams, and the strengthening after removing the concrete cover of corroded RC beams is better than direct strengthening. The corroded beams after TRC strengthening exhibited improved ductility. The energy absorption index of the TRC-strengthened corroded RC beams increased with the increase in the number of textile layers.

This study investigates the effects of flood–induced wetting on the vertical bearing capacity of steel hoops confining concrete columns. Experimental and theoretical analyses were conducted, including static and dynamic friction tests between steel plates and concrete surfaces, as well as vertical bearing capacity tests of steel hoops under water–layer conditions. The results indicate the following: (1) The friction coefficient showed minimal dependence on vertical pressure under identical conditions, and the vertical bearing capacity of steel hoops increased with higher preload applied by high–strength bolts. (2) For static friction, the coefficient was lowest under dry conditions, moderate under wet conditions, and highest with a water layer on the concrete surface. For dynamic friction, the coefficient was lowest with a water layer on the concrete surface, moderate under dry conditions, and highest under wet conditions. (3) The contact between the steel hoop and concrete column was non–uniform. Under high–strength bolt preload, close contact occurred primarily in the central region and near the wing plates of the steel hoop. Friction under vertical loading was concentrated in these regions, making them prone to local damage in practical engineering applications. (4) In dry conditions, the vertical bearing capacity calculated using either static or dynamic friction coefficients closely matched the experimental results. However, when a water layer existed between the steel hoop and the concrete column, the calculation results based on the dynamic friction coefficient were consistent with experimental values.