Deterioration of Concrete in Hydraulic Structures due to Frost Action

Climatic conditions during the winter in countries situated in the north can be considered severe. This is especially true for hydraulic structures, such as hydro power structures, dams, harbours, canals and some bridge foundations. Freezing of concrete in contact with unfrozen fresh water may have a considerable impact on the deterioration process of concrete. This paper presents results obtained in experimental investigations based on observations of superficial and internal damage to concrete in hydraulic structures in Sweden. It was shown that superficial damage at the waterline is caused by interactions between leaching, frost action and abrasion. Further, the results indicate that internal damage to some thin concrete dams has been due to formation of macroscopic ice lenses causing spalling of concrete. Knowledge about degradation mechanisms and how they interact is crucial in order to be able to perform durable repairs.