The concrete is manufactured by mixing of different material such as cement, sand and coarse aggregate. A chemical reaction happens between the water and cement and its binds all material.
A proper water-cement ratio helps the concrete to attain its maximum strength.
What is Curing of Concrete?
Curing is the process of developing concrete strength. During the process of curing of concrete absorbs the necessary water for its complete chemical action to reach its maximum strength.
The concrete will not attain the design strength immediately. The concrete has been taken 24 hours to attain its 16% of design strength and the concrete attains its full strength in 28 days.
|Days||Percentage of Strength|
What is the minimum period for curing of concrete
The curing period should continue depends upon the atmospheric conditions such as temperature, humidity and wind velocity.
The curing period also depends upon the type of cement and the nature of work.
- In case portland cement used for concrete then the curing period should not less than 7 to 14 days.
- In the case of rapid hardening cement is used, then the curing period will be 7 to 10 days.
- In cold weather conditions, the concrete should be cured for 14 days.
Types of Curing of Concrete
Based on the type of construction work, the concrete is cured by the following method. However, we have to consider the below-mentioned factors while selecting any mode of curing of concrete.
- The water loss must be prevented.
- The temperature must be kept to a minimum to scatter the heat of hydration.
By Water Ponding
The water ponding curing method is widely used to cure the concrete and this method applied for flat surfaces. A small clay bund or water-retaining material is provided around the perimeter of the surface.
The whole surface is divided into small portions by the bund and those enclosed areas filled with water.
The water ponding curing of concrete generally used for curing pavements and floor slabs.
Wet Sacks Curing and Frequent Water Spraying Method
A best curing way of a vertical member of a structure is Wet Sacks Curing and Frequent Water Spraying Method.
Columns are wrapping around them wet sacks and keeping the pot full of water as shown in below picture.
The column and wall also cured by spraying water on the surface at regular intervals.
By Sealing Curing Compounds
The concrete surface is applied with a coat of sealing curing compound immediately after finishing.
The coat prevents the evaporation of water from the concrete and concrete remains moist for long periods.
The chemical curing of concrete method applied where the scarcity of water. In this method, water is added to the hygroscopic material and sprinkled over the surface.
The hygroscopic material absorbs the moisture from the atmosphere and keeps the surface damp.
Membrane curing of concrete
The membrane curing method is widely used curing in highway construction. The membrane curing of concrete method also used in water scarcity areas.
Steam curing of concrete
The precast concrete element is often cured by steam pressure.
One more method of concrete curing, passing alternate current through freshly laid concrete for 2 hours.