What is Curing of concrete

 Curing

In this article we discussed the following

• what is curing of concrete
• Objectives of curing 
• Methods of curing 

Curing is the process  which is actively employed for  promoting the hydration of cement in a suitable environment in early stage of hardening of concrete

As per  IS-456:2000 curing is the process of prevention of moisture from the concrete while maintaining satisfactory temp.

Curing must be done for at least 3 weeks and is no case for less than 10 days 

It is carried out at temp of 5-28 degree celcius and of 90% humidity

If concrete is cured for one month its strength is nearly double than that of concrete which is exposed to air

Objectives of curing

• To keep capillary pore saturated to ensure hydration of cement
• To improve wear resisting quality
• To prevent the loss of moisture from concrete due to evaporation or any other reason

Curing can be done by any of the following method

• Shading of concrete surface
• Covering concrete surface with wet gunny bags
• sprinkling water on concrete surface
• Ponding of concrete surface Best method
• Application of curing compounds like bitumen tar acrylate chlorinated rubber, sodium silicate water glass linseed oil .  These compounds make a film fill the pores seal the surface voids and prevent evaporation
• Accelerated curing (steam infrared curing) for concrete with W/C ranging 0.3-0.7 the increased rate of strength development can be achieved by using steam curing                                               

It does not effect ultimate strength but reduces the Shear strength of the concrete