Deterioration of Concrete Used in Road Bridges Due to Freezing and Thawing
Appears on pages(s):
bridges (structures); climate; concrete construction; concrete durability; deterioration; freeze-thaw durability; structural design; surveys; Design
Concrete structures in the northern regions of Japan have a higher risk of deterioration due to freezing and thawing because of the cold climate and heavy snows. The resistance of concrete to freezing and thawing is studied actively in the laboratory in Japan, but there is still much to be studied about the deterioration of concrete structures exposed in the field. A survey of the deterioration of concrete used in road bridges was made in Iwate Prefecture, a district in northeastern Japan where there are many different climatic conditions. Over 300 bridges were examined. The majority of bridges observed were damaged to some degree by freezing and thawing. The degree of deterioration differed in different parts of the bridges. Although the main cause of deterioration is presumed to be poor construction, it can be pointed out that the lack of consideration for design of these structures adds significantly to their deterioration. The degree of deterioration also depends on regional climatic conditions. In this report, the relation between the degree of observed deterioration and the climatic conditions is discussed.