Shrinkage Cracks

Due to high temp and humidity if the rate of moisture loss from concrete raises from eveporation, cracks will appear in concrete. It also occurs due to thermal expansion and heat of hydration in concrete. Hence temp control concrete may be provided with temp below than 25OC while pouring. Shrinkage of concrete may also results in cracks. Other reasons are acid alkali reaction of aggregates, sulphates, chlorides, excess vibration, absorption of water by form work, sub grade, presence of silts in sand etc.

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