CCI Construction Materials & Methods 2

Question 1

What is the primary purpose of using a vapor barrier in a concrete slab-on-grade?

Accepted Answer

To prevent moisture migration from the subgrade into the slab

Answer

A vapor barrier (polyethylene sheet) prevents soil moisture from wicking upward through the concrete slab, protecting flooring systems and interior finishes.

Question 2

Which masonry unit classification indicates the highest structural quality per ASTM C90?

Accepted Answer

Grade N

Answer

ASTM C90 Grade N concrete masonry units are intended for general use including above- and below-grade applications exposed to moisture and weather.

Question 3

In structural steel fabrication, what does the term 'mill scale' refer to?

Accepted Answer

Iron oxide layer formed on hot-rolled steel during manufacturing

Answer

Mill scale is a flaky iron oxide layer that forms on the surface of hot-rolled steel during the manufacturing process and must be removed before painting.

Question 4

What concrete admixture type is used to reduce the water content required to achieve a given slump?

Accepted Answer

Water reducer (plasticizer)

Answer

Water-reducing admixtures (plasticizers) allow the same workability to be achieved with less water, improving the water-to-cement ratio and concrete strength.

Question 5

When inspecting reinforcing steel, 'No. 5 bar' refers to a rebar with a nominal diameter of:

Accepted Answer

5/8 inch

Answer

Rebar bar numbers correspond to the nominal diameter in eighths of an inch, so a No. 5 bar has a nominal diameter of 5/8 inch.

(CCI) Certified Construction Inspector Practice Test

(CCI) Certified Construction Inspector Practice Test

CCI Construction Materials & Methods 2