CRAZING OF CONCRETE AND THE REMEDIAL MEASURES FOR CRAZING OF CONCRETE

CRAZING OF CONCRETE AND THE REMEDIAL MEASURES FOR CRAZING OF CONCRETE

SUBRATA PAUL | CRAZING | 12-01-2019

 

What is Crazing of Concrete?

Crazing is the development of random fine cracks on the surface layer of concrete or mortar due to shrinkage of the surface layer. These cracks are intensively seen in floor and slab surface.

These cracks generally about 3mm deep and length, not more than 40mm. Sometimes these cracks are not visible in dry condition but when they are wetted, they become visible. These cracks do not affect the durability of the concrete nor the permeability and water resistance. Also, there is no effect on structural integrity due to crazing.

 Preventive Measures for Crazing of concrete:

v Troweling the surface as little as possible particularly avoiding using of steel float for finishing. Instead of steel float use Wooden float for finishing.

v Avoiding the use of neat cement powder for finishing of the concrete surface would prevent the crazing of concrete.

v Also avoid the rubbing the surface with neat cement paste, after finishing.

v Sometimes over vibrating the fresh concrete may result in bringing too much cement slurry on the top surface of concrete and this has a tendency of shrinkage which causes of crazing of concrete.

v Using of the low water-cement ration as much as possible to avoid crazing.