BCM Building Materials and Construction Methods 2

Question 1

Which roofing system type is most commonly used on low-slope commercial roofs in the US?

Accepted Answer

Single-ply membrane (TPO, EPDM, or PVC)

Answer

Clay tile roofing

Answer

Wood shake shingles

Answer

Slate roofing

Question 2

Post-tensioned concrete slabs use high-strength steel tendons to:

Accepted Answer

Apply compressive pre-stress to the concrete after it cures, improving span capacity and crack control

Answer

Connect precast concrete panels at construction joints

Answer

Reinforce concrete columns against seismic lateral loads

Answer

Anchor curtain wall systems to the building structure

Question 3

The R-value of an insulation material measures its:

Accepted Answer

Resistance to heat flow (thermal resistance)

Answer

Resistance to moisture absorption

Answer

Fire resistance in minutes

Answer

Compressive strength under load

Question 4

Tilt-up construction is a concrete building technique where:

Accepted Answer

Concrete wall panels are cast horizontally on the slab floor and then tilted up into vertical position

Answer

Precast panels are manufactured off-site and trucked to the project

Answer

Concrete is pumped into vertically standing formwork systems

Answer

Masonry walls are reinforced with horizontal grout lifts

Question 5

The purpose of control joints in concrete flatwork is to:

Accepted Answer

Create weakened planes where cracking occurs in a controlled, straight line

Answer

Provide expansion space for thermal movement in the slab

Answer

Anchor the slab to the foundation walls

Answer

Allow construction to pause between pours

Question 6

Fly ash is commonly added to concrete mixes primarily because it:

Accepted Answer

Improves workability, reduces permeability, and partially replaces Portland cement

Answer

Accelerates concrete strength gain in cold weather

Answer

Increases the unit weight of the concrete mix

Answer

Acts as an air-entraining agent for freeze-thaw resistance