Question

The table below shows different types of cement and chemical admixtures that are available for use in a concrete mix to meet different conditions of supply at a construction site. Cement type GP HE LH Admixture type Ас AEA Re WR SR Using the above table, select both the cement and admixture types that will be best suited to meet each of the requirements presented below given a change in water-to-cement ratio and cement content is permitted for each mix to meet these needs. a) Constructing a concrete box culvert for drainage use of water and soil b) Maximising the strength of concrete after 180 days age c) Minimising the extent of shrinkage in concrete after 28 days age d) Repairing a concrete member at an ambient temperature of 5°C Briefly explain your reason(s) for reaching each of the above conclusions.

Answer 1

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c) minimising extent shninkage in 26 days e : LHt Re conuet cement with conuete mix The with (low heat myd rahen ) LHC which неtand SHhing Hine неtaчders minimum will give conte shuinkye in conorete member af d)Repairing Tempenahas am bi'ent an HE t AEA The High eanly stngh (He) ground whiuh hove tiny moHe waeful at sightly меpid mоe When como uhon . Comes

into contau 7Combinahn admixtuu cing admixhune ) ninadmixhune, ( 4ir A EA dunabi l R Jлеезе B impove improve tedued tharing is wor high Cs content, zod| airly GP for eanly strengi - эн ground moHe slighky have move may Low LH ond (3A (y.) Low iSR C3A Content