Retardation of fresh concrete has several advantages as follows:
(i) A rapid hydration process results in loss in concrete strength because the concrete will have a poorer structure with a higher gel/space ratio compared with the concrete with a lower hydration rate.
(ii) During the hydration process, a substantial heat of hydration will be generated. If the hydration process is carried out too swiftly, it will cause a rapid rise in temperature and results in considerable early thermal movement in concrete.
(iii) In hot weather concreting, the loss of workability is substantial. In order to ensure sufficient compaction of fresh concrete, it is necessary to extend the time for fresh concrete to remain plastic.
This question is taken from book named – A Self Learning Manual – Mastering Different Fields of Civil Engineering Works (VC-Q-A-Method) by Vincent T. H. CHU.
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