Types of Concrete

What is the ratio of aggregate, concrete, and sand in normal strength concrete?

• 1:1:2

• 1:2:4

• 2:1:4

• 4:2:1

What is the purpose of reinforcing steel rods or cables in reinforced concrete?

• To resist compressive forces

• To improve thermal conductivity

• To enhance durability

• To resist tensile forces

What is the special technique used to create prestressed concrete?

• Adding fibers to the concrete

• Using lightweight aggregates

• Stressing the bars or tendons before applying the concrete

• Using a higher water-cement ratio

What is the advantage of using precast concrete?

• Higher tensile strength

• Faster assembly

• Lower density

• Improved thermal conductivity

What is the density requirement for lightweight concrete?

• Less than 1000kg/m3

• Between 1000kg/m3 and 1500kg/m3

• Between 1500kg/m3 and 2000kg/m3

• Greater than 2000kg/m3

What is the main advantage of ready-mix concrete?

• Higher precision

• Lower cost

• Faster setting time

• Better resistance to cracking

What is the main characteristic of self-consolidated concrete?

• It requires mechanical consolidation

• It has low thermal conductivity

• It is lightweight

• It compacts on its own without vibration

What is the minimum tensile strength for high-strength concrete?

• 20MPa

• 30MPa

• 40MPa

• 50MPa

What are the efficiency standards for high-performance concrete?

• Strength gain in early age

• Easy placement

• Longevity and durability

• All of the above

What are the main components of DURA® Ultra-High Performance 'ductile' Concrete (UHPdC)?

• Portland cement and steel fibers

• Silica fume and fine silica sand

• Polypropylene fibers and glass fibers

• All of the above