Great care is to be taken to keep the repaired patches moist for several days. In general much amount of care is taken to cure material in patches than the whole structure. The reason is, being relatively small volume of repairs and the tendency of old concrete, around it, to absorb moisture from the new material. Curing must be started as early as possible after the patch is finished to prevent early drying. The various methods used for curing repaired surfaces are given below.
Methods of Curing Repaired Concrete Works
- To keep repaired surfaces wet for the initial curing, water should be applied at regular intervals by a large brush or spraying device.
- Damp hessian may be used or wet burlap pads can be used.
- In some cases it may be difficult to hold damp hessian or wet burlap pads in position. In such a case a membrane curing compound is best suited. Best results are obtained by initial curing with water followed by sealing compound, when concrete surface is still damp.
- Deliquescent salts such as calcium chloride may be used to hasten hardening and help to keep the patch in moist condition.
- Horizontal surfaces can be cured by spraying method or by placing wet gunny bags.