Coff of thermal expansion of concrete IS 456

The change in length per unit degree Celsius temperature. Its depending upon type of aggregates. It ranges from from 0.6 to 1.3 x 10 -5 degree C

A value of 1.2 x 10 -5 degree C to 1.3 x 10 -5 degree C may be taken. The coff of thermal expansion of concrete and steel is nearly same. Hence it is the main reason to provide steel in concrete.

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