Geometric Design Test 1

From which point superelevation runoff starts?

where cross slope of the outside lane is leveled (zero)

Which of the following curve design criteria can apply to both sag and crest vertical curves?

Stopping sight distance

What is the value of maximum superelevation rate (e_max) according to ALDOT?

8%

Which of the following is NOT an input into determining superelevation transition length?

Curve length

What is the relation between radius of the horizontal curve and super elevation?

Inversely proportional

According to typical ALDOT practice, what percentage of the superelevation transition length is placed on the tangent?

80%

Which type of horizontal curve is represented by the following curve?

Compound

Which of the following factors will not affect sight distance for horizontal curves.

Cross section slope

What is the first step in the design of horizontal curve?

Determine the tangents

Which of the following is NOT considered part of the roadside clear zone?

Traveled way

Which of the following best defines Free-Flow Speed (FFS)?

The mean speed of passenger cars under low to moderate flow rates

Which of the following is NOT an ideal condition for a basic freeway segment?

20% heavy vehicles

Which type of median is generally used on freeways and rural multilane highways and is effective for surface-water drainage?

Depressed median

According to the AASHTO design guidance presented in class, what is the minimum width (in feet) typically used for a TWLTL?

10

Which of the following side slopes is generally considered non-recoverable for a run-off-road (ROR) vehicle?

1:3

What is the primary purpose of a highway shoulder?

To provide an area for vehicles to stop, particularly during emergencies

Which combination of grade characteristics has the greatest effect on heavy-vehicle performance?

Steepness and length

For a parabolic vertical curve, the vertical offset from the tangent is proportional to the ______ of the horizontal distance from the point of tangency.

Correct answer:

square of the distance

The “K” factor used in Vertical Curve design table according to AASHTO Green Book is defined as the:

required feet of curve length per 1% net change in grade

Which of the following is NOT a primary consideration in the design of vertical alignment?

Require horizontal and vertical curves to begin and end at the same stations

For roadway vertical-alignment calculations, roadway grades are designated as either __________ or ____________?

positive or negative