Curing

• All exposed  surfaces  should be covered with wet hessian or  gunny bags for curing. After about 12 hours it should be pounded with water. On  vertical faces of wall, columns  and beams, wet canvas should be retained.  Curing should be done for specified period. 
• The ponding  water  lost  due to evaporation should be continuously  replenished. 
• The difference in the curing  water  temperature and the concrete  temperature should not be  more than  11°C to prevent thermal stresses thank could result in cracking. 
• The height of buds and area of concrete  surface to be prided should be so selected that there is at least  about 25 mm of water pounded on the highest point. 
• Curing  compounds  are now easily  available. They consist of waxes,  resins, chlorinated rubber  and  solvents of  high  volatility which form  a thin  liquid membrane on the concrete  surface and results in prevention of loss of water due to evaporation to a certain extent. 
• curing compounds must be preferably  sprayed in two  layers. The second layer must  be sprayed at right  angles  to the first layer.