Review on Durability Provisions in IS456:2000 and Suggested Modifications based on Causes of Deterioration

Concrete is the most widely used material in the world next to water. For the last one and a half century, cement concrete has been extensively used for various structures which man could dream or conceive of with the misconception that they will last forever. Despite the availability of equipment for quality concrete construction, in the recent past many concrete structures have undergone premature deterioration resulting in early reconstruction or major repairs involving huge expenditures. This could be due to inadequate anticipation of severity in exposure conditions, poor quality of construction using site mixed concrete, increased severity due of environmental pollution etc. Corrosion of reinforcement is one of the major durability problems, mainly when rebar in concrete is exposed to the chlorides either contributed from the concrete ingredients or penetrated from the surrounding chloride-bearing environment. Carbonation of concrete or penetration of acidic gases into the concrete, are the other causes of reinforcement corrosion. IS 456:2000 provides various provisions for durability requirements, but some modifications are required in these provisions such as classification of exposure conditions based on causes of deterioration [1].