3. According to I.S. : 456, the number of grades of concrete mixes, is
4. The mixture of different ingredients of cement, is burnt at
5. The risk of segregation is more for
6. After casting, an ordinary cement concrete on drying
7. Hydration of cement is due to chemical action of water with
8. To obtain cement dry powder, lime stones and shales or their slurry, is burnt in a rotary kiln at a temperature between
9. Permissible compressive strength of M 300 concrete grade is
10. The standard sand now a days used in India, is obtained from
11. The maximum amount of dust which may be permitted in aggregates is
12. Proper proportioning of concrete, ensures
13. The bulk density of aggregates does not depend upon :
14. Curing
15. While compacting the concrete by a mechanical vibrator, the slump should not exceed
16. Construction joints are provided
17. An aggregate is said to be flaky if its least dimension is less than
18. The following proportion of the ingredients of concrete mix, is not in conformation to arbitrary method of proportioning
19. The increased cohesiveness of concrete, makes it
20. The ratio of the length to breadth of a wooden float, is
21. To ensure constant moisture content in aggregates
22. Workability improved by adding
23. The commonly used material in the manufacture of cement is
24. If 20 kg of coarse aggregate is sieved through 80 mm, 40 mm, 20 mm, 10 mm, 4.75 mm, 2.36 mm, 1.18 mm, 600 micron, 300 micron and 150 micron standard sieves and the weights retained are 0 kg, 2 kg, 8 kg, 6 kg, 4 kg respectively, the fineness modulus of the aggregate, is
25. Curing a concrete for long period ensures better