ot climate regic 36 Choose the appropriate type of cement us

ot climate regic 36. Choose the appropriate type of cement used in h a) Cement type II b) Cement type III c) Cement type IV d) Cement type V e) None of the above 37. In clinkering reaction: C,S reacts with Cao to produce C2S a) b) C2S reacts with Cao to produce C3S c) Cacos reacts with Cao and releases Co2 d) Cacos reacts with Co2 and releases Cao e) None of the above 38. In stage one of cement hydration, a false setting may occur du a) Addition of too much gypsum b) No addition of gypsum c) C3A reaction with water is not controlled d) Addition of too much water e) None of the above 39. Soundness test result measures: a) Hardness of aggregates b) Durability of aggregates c) Toughness of aggregates d) Cleanness of aggregates e) None of the above 40. The two minerals to be reduced for cement type V (sulfat cement (type I) are: a) Tetra-calcium alumino-ferrite and Tricalcium alumina b) Dicalcium silicate and Tricalcium aluminate c) Tricalcium aluminate and Tricalcium silicate d) Dicalcium silicate and Tricalcium silicate e) None of the above

Solution

36. C) Cement type IV : these cement have very low heat of hydration.

37. b) C₂S reacts with CaO to produce C₃S

38. b) Absence of gypsum cause the rapid stifining of cement known as false setting.

39. e) None of the above: Soundness test is a test conducted to cement to find expansion due to unreacted lime.