Condition Survey of Reinforced Concrete in Hydroelectric Power Plant Vinodol

Condition survey and testing of a RC structure was performed in the main operating building in the Hydroelectric power plant "Vinodol", which is an underground structure more than 50 years old. Within this condition survey, along with a visual inspection, examinations of the following properties were done: compressive strength, reinforcement location, carbonation depth, corrosion current, potential mapping, concrete resistance. Since the carbonation depth is deeper than the reinforcement location, the main causes of the corrosion are the carbonation process and humid environment. For determination of the corrosion rate the galvanostatic pulse technique was applied. This is a non-destructive technique and determines the free corrosion potential and corrosion current. The results of these measurements are presented in this paper. The correlation of the carbonation depth and corrosion current are discussed.