1. Ultrasonic pulse velocity test to measure the strength of concrete is
- used to obtain estimate of concrete strength if finished concrete elements.
- used to measure strength of wet concrete.
- a non-destructive test.
Which of the above statement are correct?
- i and iii
- ii and iii
- i and ii
- i, ii and iii
2. In the case of concrete where mineral admixtures or blended cements are used, it is recommended to cure the concrete for the minimum peri0d of
- 10 days
- 20 days
- 5 days
- 14 days
3. What is the correct sequence of operations involved in concrete production?
- Batching → Mixing → Handling → Transportation
- Mixing → Batching → Handling → Transportation
- Transportation → Handling → Mixing → Batching
- Handling → Transportation → mixing → Batching
4. Shrinkage in a concrete occurs due to
- usage of bad cement
- usage of bad aggregates
- loss of moisture by evaporation
- loss of water in bleeding
5. The class of fire, as per IS:1641-1960, which a structural element of grade 1 can withstand, is
- High
- Low
- Very high
- Medium
6. Which of the following grades of concrete in R.C.C. is recommended for severe exposure condition by BIS?
- M20
- M25
- M15
- M30
7. Relevant IS code for specification of baten type concrete mixers is
- IS : 2506
- IS : 2502
- IS: 1786
- IS: 1791
8. A curve showing percentage passing of aggregate v/s sieve size on abscissa of aggregate of horizontal portion for certain range indicates
- continuous grading
- mix grading
- gap grading
- porous grading
9. As per IS code provision the tolerance on placing of reinforcements in a structural member having effective depth more than 200 mm shall be
- ± 15 mm
- ± 20 mm
- ± 25 mm
- ± 10 mm
10. A concrete mix has entrapped air about 1% results in
- requires less quantity of water
- poor quality of concrete
- average quality of concrete
- improved quality of concrete
11. Which of the following Indian standard is referred to determine zone of fine aggregate?
- IS 1237
- IS 456
- IS 1893
- IS 383
12. The property of the ingredients to separate from each other while placing the concrete is called
- Segregation
- Compaction
- Shrinkage
- Bulking
13. Which of the following shapes of aggregate requires minimum water to achieve a desired workability?
- Rounded
- Cubical
- Square
- Elongated
14. Which of the following grades of concrete is recommended by BIS for moderate exposure condition?
- M10
- M15
- M25
- M20
15. Which of the following categories of sand shows maximum bulking at certain percentage of moisture content?
- Fine sand
- Medium sand
- Coarse sand
- None of the above
16. Reduction of pH value in concrete is referred as
- Hydration
- Carbonation
- Rich mix
- Pozzolanic reaction
17. Which of the following coarse aggregate requires minimum cement paste?
- Rounded
- Irregular
- Angular
- Flaky
18. A mortar for which both cement and lime is mixed is called
- Lime mortar
- Cement lime mortar
- Gauged mortar
- Hydraulic mortar
19. In 500 gm sample of coarse aggregate, there are 100 gm flaky particles and 80 gm elongated particles. What are the flakiness and elongation indices (total) as per IS?
- 40%
- 36%
- 18%
- 4%
20. One of the main demerits in using the lime mortar is that it
- is not durable
- does not set quickly
- swells
- is plastic