Concrete Technology Questions and Answers - Bulking of Aggregates

1. What do you mean by bulking?
a) The volume increase of fine aggregate due to presence of moisture content in it
b) The moisture present in aggregate forms a film around each particle
c) Fine aggregate shows completely realistic volume
d) The state of setting someone or something apart from others

Answer: a
Explanation: The volume increase of fine aggregate due to presence of moisture content is known as bulking. Fine sand bulks more as compared to coarse sand.

2. Fine aggregate do not show any bulking when it is absolutely dry.
a) True
b) False

Answer: a
Explanation: Fine aggregate do not show any bulking when it is absolutely dry or completely saturated.

3. What is the percentage of bulk if fine aggregates manufactured by extremely fine sand?
a) 20
b) 30
c) 40
d) 50

Answer: c
Explanation: Extremely fine sand particularly the manufactured fine aggregate bulks as much as about 40%.

4. Bulking ___________ with increase in moisture.
a) Increase
b) Decrease
c) First increase then decrease
d) First decrease then increase

Answer: c
Explanation: Bulking increases with increase in moisture content upto a certain limit and beyond that the further increase in moisture content results in decrease in volume.

5. Fine sand bulks __________ than coarse sand.
a) Less
b) More
c) Equal
d) Depends on volume

Answer: b
Explanation: Fine sand bulks more as compared to coarse sand, i.e. percentage of bulking in indirectly proportional to the size of particle.

6. If h = height of sand when moist and h1 is the height when saturated then what is the percentage of bulking?
a) {(h-h1)/h1}*100
b) {(h1-h)/h1}*100
c) {(h-h1)/h}*100
d) {(h1-h)/h}*100

Answer: a
Explanation: It is the formula to calculate the percentage of bulking. Percentage in bulking = {(h-h1)/h1}*100.

7. Which apparatus we don’t need to calculate the bulking of fine aggregates?
a) Measuring cylinder
b) Weighing balance
c) Steel rule
d) Vicat’s mould

Answer: d
Explanation: Vicat’s mould don’t come in use to calculate the bulking percentage because it is used to find initial and final setting time.

8. What is bulking of coarse aggregates?
a) More than sand
b) Less than sand
c) Equal than sand
d) Negligible

Answer: d
Explanation: Bulking is indirectly proportional to the particle size of the aggregates. Size of coarse aggregates is more hence negligible bulking.

9. If the moisture content of 5 to 10% by weight, then the bulking of sand is increased by __________
a) 20
b) 30
c) 40
d) 50

Answer: d
Explanation: With the moisture content of 5 to 10% by weight, the bulking of sand is increased by 50.

10. When sand is fully dry then it’s volume is ____________
a) Equal
b) Less
c) More
d) Can’t say

Answer: a
Explanation: When the sand is fully dry then there is 0 bulking in it. Therefore, the volume of the same will be same.