Effect of corrosion on the natural frequency in a scaled-down reinforced concrete containment vessel specimen

Abstract

This study presents a laboratory investigation to evaluate the natural frequency variation of the scaled-down reinforced concrete containment vessel specimen subjected to an accelerated reinforcement corrosion. The states of damage in the scaled-down specimen were assessed through measurement of the concrete resistivity, the open circuit potential, the corrosion rate and the natural frequencies. Those electrochemical parameters related with steel corrosion were extensively compared. The test results indicated that the corrosion behaviours of steel in the scaled-down specimen and the natural frequencies before and after the immersion were different. The changes in the natural frequencies were consistent with the material degradation of the concrete vessel specimen. The natural frequencies decreased with the increasing corrosion rate or the decreasing resistivities for the specimen at a higher mode, but would be a slight change for the specimen at the natural frequency of the first mode.