FIBER OPTIC COLORIMETRY TECHNIQUE FOR BN-SITU HEASUREMENT OF CORROSION IN CIVIL STRUCTURES

摘要

Corrosion of civil structures (bridges, buildings) & roadways is a persistent problem. Both steel and reinforced concrete structures are subject to corrosive attack. However, due to the difficulty in repairing reinforced concrete, its corrosion problems are perhaps more critical. Engineers have been concerned with the manner in which the pre-stressed concrete behaves during corrosion. The reinforcement steel on corrosion swells to a volume that is about five times larger than that of the original steel. This swelling causes spailing and cracking of the concrete, which further exposes the reinforcement to corrosion and can promote serious structural damage. In the USA alone, annual losses in time, labor, materials and systems due to corrosion problems have been estimated in the billions of dollars. Besides the economics of corrosion damage to buildings and highway infrastructures, there is a safety concern regarding structures with reinforced concrete exposed to harsh corrosive environments. Therefore periodical inspections are often carried out to monitor their safety.