Behavior of hyperstatic beams corroded and repaired with mortar

One of the main causes of the premature deterioration of concrete structures is reinforcement corrosion. This process supposes that with the anodic region's metal dissolution, the reinforced cross section loss will be the immediate effect of the corrosion. This work reaches a better knowledge of the corrosion influence on hyperstatic reinforced concrete structures damaged by corrosion. Seven hyperstatic reinforced concrete beams (3000 mm long, 15x20 mm cross section, 25 mm cover) were made with 25 MPa concrete compressive strength, and 3% of NaCl was added to the mix in order to induce corrosion in the bottom of the mid-span and the top of the middle support. A galvanostatic corrosion system was employed to accelerate the corrosion process. During all the tests, the beams were instrumented with strain gauges and load cells to evaluate the strains and load bearing capacity by the beams during the tests. After the determination of steel cross section's loss (estimated with Faraday's law), the beams' damaged zones were repaired with mortar only to carry out the ultimate load test. Study results demonstrated that the beams' reparation was successful, despite just the repairing of the beams with mortar and without steel addition. Results also showed a repaired cross section's stiffness increase and bearing the same efforts that bore the control beam.