Concrete Technology MCQ – Aggregate MCQ

271. Fineness modulus is

1. the ratio of fine aggregates to coarse aggregate
2. the ratio of fine aggregates to total aggregate
3. an index which gives the mean size of the aggregates used in a mix
4. none of the above

272. For a satisfactory workable concrete with a constant water cement ratio, increase in aggregate cement ratio

1. decrease the strength of concrete
2. does not change the strength of concrete
3. increase the strength of concrete
4. none of these

273. Which of the following is a field test for measuring the consistency of plastic concrete?

1. Le Chatelier’s Test
2. Compaction Factor Test
3. Elongation Index Test
4. Kelly Ball Test

274. Which of the following is not a test for measuring workability of concrete?

1. Slump Test
2. Flow Test
3. Std. Consistency Test
4. Kelly Ball Test

275. To what, is Ease related in concrete technology?

1. Geology of fresh concrete
2. Rheology of fresh concrete
3. Mineralogy of fresh concrete
4. Ecology of fresh concrete

276. The aggregate crushing value for concrete as per Indian conditions varies from

1. 30-45%
2. 18-27%
3. 50-65%
4. 5-10%

277. The thermal coefficient of concrete is

1. 4.5 × 10^-6 /°C – 2.5 × 10^-6 /°C
2. 25 × 10^-6 /°C – 20 × 10^-6 /°C
3. 8 × 10^-6 /°C – 10× 10^-6 /°C
4. 0.5 × 10^-6 /°C – 1 × 10^-6 /°C

278. The required workability of concrete in terms of slump for an ordinary reinforced cement concrete (RCC) work for beams and slabs is

1. 25-30 mm
2. 40-45 mm
3. 120-150 mm
4. 50-100 mm

279. Choose the correct statement:

1. The strength of fully compacted concrete is inversely proportional to the water cement ratio.
2. The strength of fully compacted concrete is directly proportional to the water cement ratio.

1. Statement (i) is true
2. Statement (ii) is true
3. Both the statements (i) and (ii) are true
4. Both the statements (i) and (ii) are false
5. Information insufficient

280. In the context of air entrainment in fresh concrete consider the following statements:

Statement-1: Air entrainment is required in cases when concrete is likely to be subjected to alkali aggregate reaction.
Statement-2: Air entrainment has the effect of increasing the workability of concrete at the same unit water content.

Which of the following is CORRECT?

1. Statement-1 is TRUE and Statement-2 is FALSE
2. Both statements are FALSE
3. Both statements are TRUE
4. Statement-1 is False and Statement-2 is TRUE