250+ TOP MCQs on Curing of Hardened Concrete and Answers

Concrete Technology Problems on “Curing of Hardened Concrete”.

1. The slump would not exceed 50 mm when compacting concrete with vibrators.
a) True
b) False
Answer: a
Clarification: Segregation means concrete cement slurry & fine aggregates &coarse aggregate collapsed & have no slump & after hardening no strength but workability is the checking the concrete how much time used after mixing.

2. When vibrators are used for compaction, the consistency of concrete depends upon the ___________
a) Type of mix
b) Efficiency of vibrator
c) Placing conditions
d) Type of mix, efficiency of vibrator, pacing conditions
Answer: d
Clarification: When vibrators are used for compaction, the consistency of concrete depends upon the Type of mix, efficiency of vibrator, pacing conditions.

3. Which of the following statement is correct while compacting concrete with vibrators?
a) The vibrator should be inserted horizontally
b) The vibrator should not be immersed through a full depth of freshly laid concrete
c) The vibrator should not touch the form surface
d) The vibrator should touch the form surface
Answer: c
Clarification: If there is a considerable amount of time lapse between the placements of subsequent lifts, it may be necessary to re vibrate the previous lift prior to placing additional concrete to minimize the potential for pour lines and cold joints.

4. The levelling operation that removes humps and hollows and give a true, uniform concrete surface is called ____________
a) Screeding
b) Floating
c) Troweling
d) Compacting
Answer: a
Clarification: The levelling operation that removes humps and hollows and give a true, uniform concrete surface is called Screeding.

5. The final operation of finishing the concrete surface is called _____________
a) Screeding
b) Floating
c) Troweling
d) Compacting
Answer: c
Clarification: The final operation of finishing the concrete surface is called Troweling.

6. The process of removing the irregularities from the surface of concrete left after screeding is called floating.
a) True
b) False
Answer: a
Clarification: The process of removing the irregularities from the surface of concrete left after screeding is called floating.

7. The process of hardening the concrete mixes by keeping its surface moist for a certain period is called ____________
a) Curing
b) Floating
c) Troweling
d) Compacting
Answer: a
Clarification: The process of hardening the concrete mixes by keeping its surface moist for a certain period is called curing.

8. After the curing of 28 days, the concrete gains strength upto _____________
a) 40%
b) 60%
c) 80%
d) 100%
Answer: d
Clarification: After the curing of 28 days, the concrete gains strength upto 100 percentage.

9. The construction joints in cement concrete ___________
a) Should be located where bending moment is large
b) Should be located where shear force is large
c) Should not be provided at the corners
d) Should be spaced at a distance of 3 m apart in case of huge structures
Answer: c
Clarification: The construction joints in cement concrete should not be provided at the corners.

10. For compacting large sections of mass concrete in structures, the type of vibrator used is ________________
a) Internal vibrator
b) External vibrator
c) Screed vibrator
d) Internal and Screed vibrator
Answer: a
Clarification: For compacting large sections of mass concrete in structures, the type of vibrator used is internal vibrator.