In case of hand mixing of concrete, the extra cement to be added is__________________?

Related Mcqs:

1. As compared to ordinary portland cement, high alumina cement has______________?

   A. higher initial setting time but lower final setting time
   B. lower initial setting time but higher final setting time
   C. higher initial and final setting times
   D. lower initial and final setting times

2. Maximum quantity of water needed per 50 kg of cement for M 15 grade of concrete is_______________?

   A. 28 liters
   B. 30 liters
   C. 32 liters
   D. 34 liters

3. Minimum grade of concrete to be used in reinforced concrete as per IS:456-1978 is_____________?

   A. M15
   B. M20
   C. M 10
   D. M25

4. As compared to ordinary portland cement, use of pozzuolanic cement_______________?

   A. reduces workability
   B. increases bleeding
   C. increases shrinkage
   D. increases strength

5. The percentage of voids in cement is approximately_______________?

   A. 25%
   B. 40%
   C. 60%
   D. 80%

6. Strength of concrete increases with________________?

   A. increase in water-cement ratio
   B. increase in fineness of cement
   C. decrease in curing time
   D. decrease in size of aggregate

7. Admixtures which cause early setting, and hardening of concrete are called_______________?

   A. workability admixtures
   B. accelerators
   C. retarders
   D. air entraining agents

8. 1% of voids in a concrete mix would reduce its strength by about______________?

   A. 5%
   B. 10 %
   C. 15%
   D. 20%

9. In reinforced concrete footing on soil, the minimum thickness at edge should not be less than______________?

   A. 100 mm
   B. 150 mm
   C. 200 mm
   D. 250 mm

10. The effect of adding calcium chloride in concrete is________________?

    1. to increase shrinkage
    2. to decrease shrinkage
    3. to increase setting time
    4. to decrease setting time
    The correct answer is?
    A. (1) and (3)
    B. (1)and(4)
    C. (2)and (3)
    D. (2)and (4)