BCE Construction & Building Materials 5

Question 1

What is the primary reason for using air-entrained concrete in cold climates?

Accepted Answer

Resist freeze-thaw damage

Answer

Entrained air voids provide pressure relief as pore water freezes and expands, preventing internal cracking from freeze-thaw cycling.

Question 2

Which glass product is produced by rapidly cooling molten glass to create compressive surface stresses, making it 4-5 times stronger than annealed glass?

Accepted Answer

Tempered glass

Answer

Tempering creates surface compression that must be overcome before tensile cracking begins, increasing strength and causing the glass to dice into small cubes when broken.

Question 3

What is the minimum concrete cover over steel reinforcement in a building column exposed to weather per ACI 318?

Accepted Answer

2 in

Answer

ACI 318 requires a minimum 2-inch cover for concrete exposed to weather for bars larger than No. 5, protecting reinforcement from corrosion.

Question 4

Galvanizing steel involves coating it with which metal to provide sacrificial corrosion protection?

Accepted Answer

Zinc

Answer

Zinc galvanizing provides both a physical barrier and cathodic (sacrificial) protection, oxidizing preferentially to protect the base steel.

Question 5

What does 'slump' measure in fresh concrete?

Accepted Answer

Workability/consistency

Answer

The slump test (ASTM C143) measures the vertical drop of a standard cone of concrete, indicating its workability and relative water content.

BCE - Bachelor of Civil Engineering Practice Test

BCE - Bachelor of Civil Engineering Practice Test

BCE Construction & Building Materials 5