Rehabilitation / retrofitting / strengthening of concrete members is carried out with help of high grade materials. All of them have tendency of high exotherm generating during polymerization of their ingredients. This has to be brought to balanced thermal equilibrium. Dampening of the surface is the usual method adopted for the purpose.

Curing activity is also called as strength gaining phenomena.

Two points of importance connected with curing are discussed here.

First point is insufficient efforts to compensate for polymerization exotherm. This results in generation of internal and surface cracks through which exotherm heat tries its escape way. Unfortunately some of these cracks turn to be structural cracks at long run and emerges as serious structural defect.

Second point is insufficient time period provided for full polymerization of total quantum of ingredients of the rehabilitation matrix which is also covered under the domain of curing. Polymerization period for each category of rehabilitation material is specific and defined. It is mandatory and essential to allow total polymerization time period. All designed and desired parameters of finally rehabilitated structure are achieved only after this polymerization process is complete. If under any circumstances this period is not allowed before putting the structure to its desired functioning, there are serious chances (with high probability) that the structure might buckle and no more remain capable to sustain the load and other stresses to which the structure would be exposed on later date. This is very typical challenge. No NDT result would be below reject limit. No reinforcement would be found corroded. No external force causing distress would be identified and still the structure may show hollow sound at some local pocket! Internal distress due to buckling or typical shear is the reason for this and insufficient time allowed for polymerization process – curing period – is the reason for the distress as stated above.

Any compromise in curing activity and curing period is a serious threat to the rehabilitated structure which was already damaged and which has been rehabilitated.