PYQs of GATE ESE and PSU for SSC JE / RRB JE [Part - 1]

BUILDING MATERIALS

1. In the manufacture of definite proportion of argillaceous and calcareous are burnt at temperature of

Ans- 1450°C

2. The percentage of gypsum added to the clinker in the manufacturing process

Ans - 2.5 - 3.5 

3. The setting and hardening of cement 

after addition of water is due to

Ans - Hydration of some of constituent compound of cement 

4. The contribution compound of cement in decreasing order of rate of hydration are 

Ans - C3A,C3S and C2S 

5. When water is added to cement

Ans - heat is generated

6. Initial setting time is maximum for 

Ans - Low heat portland pozzolana cement

7. In medium strength concrete water cement ratio should not be less than

Ans - 0.4

8. An excess of free lime in Portland Cement cause 

Ans - Unsoundness in the product

9. In air permeability test , specific surface (in mm2/gm ) is of the order of 

Ans - 225000 - 350000

10. The cement used in the construction of dock and harbour 

Ans - Sulphate resisting portland cement