What is the need for watering a newly constructed wall?

The first three days are most critical in the life of cement mortar or concrete. The reaction of cement with water is exothermic. This liberation of heat is called `heat of hydration'. The rate of `heat of hydration' is faster in the early period and it continuously decreases at a slow rate in the foreseeable future. For the early period of hydration, water is essential. So, curing is necessary for a newly constructed wall or any structure. If proper curing is not done, an anhydrate compound will be formed. This will result in problems of durability. Curing increases compressive strength, improves durability, impermeability and abrasion resistance. Curing will ensure adequate moisture within mortar or concrete and it also ensures sufficient water for continuous hydration process. If the newly constructed wall is left exposed without curing there is a continuous loss of moisture due to evaporation and self-desiccation. This will cause dry shrinkage and result in poor bondage, incomplete chemical reaction and loss of strength, due to which surface cracks and air cracks occur. So watering is needed for avoiding the above structural defects in a newly constructed wall and all concrete structures.

Source: thehindu.com