FS Route and Transportation Surveys 2

Question 1

A parabolic vertical curve is preferred over a circular vertical curve in route surveying primarily because:

Accepted Answer

It provides a constant rate of change of grade

Answer

The parabola's mathematical property of constant second derivative means the grade changes at a uniform rate, making design and staking calculations straightforward.

Question 2

The prismoidal formula for computing earthwork volumes between two cross-sections is:

Accepted Answer

V = L × (A1 + 4Am + A2) / 6

Answer

The prismoidal formula V = L(A1 + 4Am + A2)/6 uses the end areas and the area of the middle section (Am) for a more accurate volume than the average end area method.

Question 3

In earthwork terminology, 'swell' refers to:

Accepted Answer

The increase in volume when in-situ material is excavated and loosened

Answer

Swell is the increase in volume that occurs when compacted in-place soil is excavated and broken up, because air voids are introduced between particles.

Question 4

The K-value for a parabolic vertical curve is defined as:

Accepted Answer

The length of curve (L) divided by the algebraic difference in grades (A)

Answer

K = L/A, where L is the curve length in feet and A is the absolute algebraic difference in grades in percent; it represents the horizontal distance needed to achieve a 1% change in grade.

Question 5

A crest vertical curve is used when:

Accepted Answer

A positive grade is followed by a negative or less steep positive grade

Answer

A crest (summit) vertical curve occurs when the algebraic difference in grades produces a curve that is concave downward, connecting a positive grade to a negative or flatter grade.

FS - Fundamentals of Surveying Exam Practice Test

FS - Fundamentals of Surveying Exam Practice Test

FS Route and Transportation Surveys 2