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

Related Mcqs:

1. The most commonly used admixture which prolongs the setting and hardening time is_______________?

   A. gypsum
   B. calcium chloride
   C. sodium silicate
   D. all of the above

2. 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

3. Approximate value of shrinkage strain in concrete, is________________?

   A. 0.003
   B. 0.0003
   C. 0.00003
   D. 0.03

4. Workability of concrete is directly proportional to________________?

   A. aggregate cement ratio
   B. time of transit
   C. grading of the aggregate
   D. all of above

5. Workability of concrete is inversely pro¬portional to______________?

   A. time of transit
   B. ‘vater-cement ratio
   C. the air in the mix
   D. size of aggregate

6. For concreting of heavily reinforced sections without vibration, the workability of concrete expressed as compacting factor should be________________?

   A. 0.75-0.80
   B. 0.80-0.85
   C. 0.85 – 0.92
   D. above 0.92

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

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

8. If nominal shear stress tv exceeds the design shear strength of concrete xc, the nominal shear reinforcement as per IS : 456-1978 shall be provided for carrying a shear stress equal to__________________?

   A. xv
   B. xc
   C. xv – TC
   D. Tv + Tc

9. For a reinforced concrete section, the shape of shear stress diagram is_______________?

   A. wholly parabolic
   B. wholly rectangular
   C. parabolic above neutral axis and rectangular below neutral axis
   D. rectangular above neutral axis and parabolic below neutral axis

10. The purpose of reinforcement in prestressed concrete is________________?

    A. to provide adequate bond stress
    B. to resist tensile stresses
    C. to impart initial compressive stress in concrete
    D. all of the above