Concrete Technology MCQ – Aggregate MCQ

241. Consolidation of concrete should be proceed

1. Before mixing
2. Before placing
3. Immediately after mixing
4. Immediately after placing

242. For R.C.C. construction, the maximum size of coarse aggregate is limited to

1. 10 mm
2. 15 mm
3. 20 mm
4. 25 mm

243. According to Indian Standard specifications, the concrete should be cured under a humidity of

1. 30%
2. 50%
3. 60%
4. 90%

244. The minimum water-cement ratio for durable concrete is

1. 0.8
2. 0.4
3. 0.2
4. 0.5

245. The durability of concrete is proportional to

1. Sand content
2. Water-cement-ratio
3. Cement-aggregate ratio
4. Aggregate-water ratio

246. A concrete mixer is specified by

1. the volume of the mixing drum
2. horse power of prime over
3. volume of mixed concrete discharged after mixing of each batch
4. mixer drum speed

247. Air entraining agent is commonly mixed in concrete to control

1. evaporation
2. expansion
3. water cement ratio
4. contraction

248. The property of aggregate, which can be measured by the impact value test is known as

1. Flakiness
2. Toughness
3. Hardness
4. Resistance to weathering

249. The laboratory slump result of the fresh concrete is between 25-50 mm. The degree of workability of such concrete is

1. very low
2. low
3. medium
4. high

250. Capacity of concrete to bear imposed stresses safely is called as

1. compressive strength
2. shear strength
3. durability
4. resistance