Concrete Technology MCQ – Aggregate MCQ

171. For RCC construction the maximum size of coarse aggregate is limited to

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

172. Transition Zone represents

1. the region between the particle of coarse aggregate & hardened cement paste
2. the region between the past phase and plane of weakness
3. the region between plane of weakness and the hardened paste
4. the region between aggregate phase and plane of weakness

173. Aggregate impact value gives an indication of aggregate?

1. Wearing capacity
2. Water resistance
3. Water absorption
4. Toughness

174. Which one of the following is employed to determine the strength of hardened concrete of an existing concrete structure?

1. Bullet test
2. Kelly ball test
3. Rebound hammer test
4. Cone penetrometer test

175. Workability of a concrete mix with low water cement ratio is determined by

1. Tensile strength test
2. Water content test
3. Cube compression test
4. Compaction factor test

176. If 1000 gms of sand is sieved through 4.75 mm, 2.36 mm, 1.18 mm, 600 micron, 300 micron and 150 micron standard sieves and the weights retained are 0 gms, 100 gms, 150 gms, 200 gms, 350 gms and 200 gms respectively, then the fineness modulus of the sand is

1. 2.60
2. 2.00
3. 2.90
4. 2.75

177. Strength of concrete increases with

1. increase in water cement ratio
2. increase in fineness of cement
3. decrease in curing time
4. decrease in size of aggregate

178. The individual variation between test strength of concrete cube sample should not be more than

1. ± 10% of average
2. ± 5% of average
3. ± 15% of average
4. ± 20% of average

179. The compressive strength of 100 mm cube of concrete as compared to 150 mm cube is

1. less
2. more
3. equal
4. less or more as per grade of concrete

180. Harsh mix of concrete

1. lacks plasticity
2. is cohesive
3. has high cement content
4. can be easily moulded