31. Which type of aggregate is commonly used for the construction of concrete blocks and pavers?
a) Crushed granite
b) River sand
c) Lightweight expanded clay
d) Recycled concrete
View Answer
Correct answer: a) Crushed granite
Explanation: Crushed granite is often used as an aggregate in the production of concrete blocks and pavers due to its strength, durability, and aesthetic appeal.
32. Which property of aggregates is important for achieving good workability in concrete?
a) Angularity
b) Absorption capacity
c) Gradation
d) Flakiness index
View Answer
Correct answer: c) Gradation
Explanation: Gradation, which refers to the distribution of particle sizes in aggregates, plays a crucial role in achieving good workability in concrete by optimizing the particle packing and ensuring a dense and cohesive mix.
33. Which type of aggregate is commonly used as a bedding material for underground utilities?
a) Pea gravel
b) Fine sand
c) Crushed limestone
d) Lightweight expanded shale
View Answer
Correct answer: a) Pea gravel
Explanation: Pea gravel, with its smooth and rounded particles, is often used as a bedding material for underground utilities to provide stability, drainage, and protection against pipe damage.
34. Which test is used to determine the soundness of aggregates subjected to wetting and drying cycles?
a) Los Angeles abrasion test
b) Aggregate crushing value test
c)Sodium sulfate soundness test
d) Slump test
View Answer
Correct answer: a) Los Angeles abrasion test
Explanation: The Los Angeles abrasion test is commonly used to determine the soundness of aggregates by subjecting them to repeated cycles of abrasion and impact, simulating the effects of wetting and drying.
35. Which type of aggregate is commonly used for the construction of sports fields and playgrounds?
a) Fine sand
b) Rubber granules
c) Crushed stone
d) Lightweight expanded clay
View Answer
Correct answer: b) Rubber granules
Explanation: Rubber granules, made from recycled tires, are often used as an aggregate in the construction of sports fields and playgrounds due to their shock-absorbing properties and ability to reduce injuries from falls.
36. Which property of aggregates affects the workability of self-consolidating concrete (SCC)?
a) Specific gravity
b) Particle shape
c) Absorption capacity
d) Gradation
View Answer
Correct answer: b) Particle shape
Explanation: The shape of aggregates is particularly important for self-consolidating concrete (SCC), as it affects the flowability and ability of the concrete to self-level and fill complex forms without segregation.
37. Which type of aggregate is commonly used as a filter material in drainage systems?
a) Crushed limestone
b) River sand
c) Lightweight expanded clay
d) Gravel
View Answer
Correct answer: d) Gravel
Explanation: Gravel, with its coarse and porous nature, is frequently used as a filter material in drainage systems to allow water to pass through while preventing the migration of fine particles.
38. Which test is used to evaluate the resistance of aggregates to polishing and skid resistance?
a) Specific gravity test
b) Los Angeles abrasion test
c) Aggregate impact value test
d) Micro-Deval abrasion test
View Answer
Correct answer: d) Micro-Deval abrasion test
Explanation: The Micro-Deval abrasion test assesses the resistance of aggregates to polishing and skid resistance by subjecting them to abrasion in a rotating drum with steel spheres.
39. Which type of aggregate is commonly used in the production of terrazzo flooring?
a) Crushed granite
b) Natural sand
c) Recycled concrete
d) Colored glass chips
View Answer
Correct answer: d) Colored glass chips
Explanation: Colored glass chips are often used as an aggregate in the production of terrazzo flooring to create decorative patterns and a unique visual appeal.
40. Which property of aggregates is important for achieving good bond strength between the aggregate and cement paste in concrete?
a) Surface texture
b) Moisture content
c) Specific gravity
d) Alkalinity
View Answer
Correct answer: a) Surface texture
Explanation: The surface texture of aggregates plays a crucial role in achieving good bond strength between the aggregate and cement paste in concrete by providing mechanical interlocking and increasing the surface area for adhesion.
