Curing Of Concrete Methods:
Concrete surfaces arc kept wet for a certain period after placing concrete. It is termed as curing of concrete.
Purposes or Importance of Curing Of Concrete Methods:
( 1) Curing protects concrete surfaces from sun and wind.
(2) The presence of water is necessary to induce the chemical reaction of setting the concrete. Generally, there is a sufficient amount of water during mixing to cause the concrete to harden. But it is necessary to retain water until the concrete is completely hardened.
(3) Concrete strength increases with age if curing is efficient. This increase in energy is sudden and rapid in the initial phase and will continue slowly for an indefinite period.
(4) By proper curing, durability, and impermeability of concrete arc increased and shrinkage is reduced.
(5) Resistance to concrete corrosion is substantially increased by proper curing.
Period of curing:
It depends on the type of cement and the nature of the work. For ordinary Portland cement, the curing period is approximately 7 to 14 days. If quick hardening cement is used, the curing period can be significantly reduced.
Following re The Curing Of Concrete Methods:
The methods of curing are largely dependent on nature. of work, weather conditions, and economic considerations.
They are divided broadly into two categories:
( 1) For vertical surfaces, curing is difficult. It is generally done by spraying water at intervals after formwork is removed. Wooden formwork should be coated with oil from the inside and during the hot season, water should be sprayed to the outside of the formwork. Alternatively, the exposed surface of concrete may be covered with hanging canvass which may be maintained wet.
(2) For horizontal surfaces such as road slabs, floors, etc., curing can be done by spraying, ponding pr covering the concrete with moist earth, sand, or wet gunny bags. For flat horizontal surfaces, ponding is an effective method and it consists of little earthen dams that are built over the entir~ surface to be cured. The squares thus formed are then flooded with a water to a depth of about 50 mm or so. To prevent evaporation, the surface of fresh concrete may hr covered with an impervious membrane.
Also Read: Corrosion Of Steel In Concrete