NETTCP Roadway Design & Maintenance 5

Question 1

What pavement layer is responsible for distributing wheel loads to reduce stress on the subgrade?

Accepted Answer

Base course

Answer

The base course distributes applied wheel loads over a broader area of subgrade, reducing stress concentrations that would cause rutting or subgrade failure.

Question 2

Which New England-specific environmental regulation most commonly affects highway drainage design?

Accepted Answer

Section 404 of the Clean Water Act regulating wetland fill

Answer

Section 404 of the Clean Water Act requires permits for discharge of fill material into wetlands, which are abundant in New England and frequently impacted by highway drainage work.

Question 3

A roadway maintenance crew discovers delamination between an overlay and the existing pavement. What was the MOST likely cause?

Accepted Answer

Inadequate or missing tack coat application

Answer

Delamination between pavement layers is most commonly caused by insufficient tack coat, which provides the bond between the new overlay and existing surface.

Question 4

When establishing horizontal alignment in mountainous New England terrain, which design constraint MOST limits the use of sharp curves?

Accepted Answer

Maximum allowable superelevation combined with design speed

Answer

Maximum superelevation rate (typically 8–10% for highway design) combined with design speed sets the minimum curve radius that can safely be used.

Question 5

What is the primary reason highway agencies in New England apply sand or sand-salt mixtures to icy pavements rather than salt alone at very low temperatures?

Accepted Answer

Sand provides friction when road salt loses effectiveness below about 15°F (−9°C)

Answer

Road salt loses significant deicing effectiveness below approximately 15°F, so sand is applied to provide mechanical friction on icy surfaces when salt cannot melt ice.

(NETTCP) New England Transportation Technician Certification Program Practice Test

(NETTCP) New England Transportation Technician Certification Program Practice Test

NETTCP Roadway Design & Maintenance 5