VDOT SOILS AND AGGREGATE
COMPACTION EXAM REVIEW
QUESTIONS AND ANSWERS 2026
VERIFIED.
T or F - The voids in a saturated soil are partly filled with water and partly filled with air. -
ANS False - They are completely filled with water
What classification system does VDOT use to classify soils? - ANS AASHTO and Unified Soil
Classification System
___ refers to the texture and firmness of a soil - ANS Consistency
Silt and clay are made up of particles that are smaller than the ___ sieve. - ANS No. 200
(75um)
What is the distribution of various particles sizes within the material? - ANS Gradation
___ means that the particles in a mixture are sized so that they fill most of the voids; there is
very little space in between soil or stone particles - ANS Dense graded
What is the moisture content at which a soil begins to behave like a liquid called? -
ANS Liquid Limit
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, What is the behavior of a material where the material deforms under load and does not go back
to it's original shape called? - ANS Plasticity
What is the moisture content at which a soil can be compacted to its maximum dry density with
the least amount of compactive effort called? - ANS Optimum Moisture Content
T or F - A soil that contains a high percentage of fines is more affected by water than one with a
low percentage of fines - ANS True
T or F - Open graded aggregates are used in a pavement to give the structure more strength -
ANS False - Dense graded aggregates are used in a pavement to give the structure more
strength
T or F - Clearing and Grubbing is required in fill sections less than 5 feet in depth, in borrow
areas before excavation can begin, and in all cut sections. - ANS True
In fill sections where stumps may be left in place, they must be no more than ___ high -
ANS 6 inches
___ means to crown surface of embankment, roll surface of embankment smooth, direct water
to appropriate erosion and siltation controls - ANS Grading to Drain
What is the first lift of embankment material placed in swampy areas called? - ANS Work
Platform
How should layers of embankment material be placed? - ANS Placed with uniform thickness
and parallel to finished grade
Material is being placed 15 feet below the proposed subgrade in a rock fill. The maximum
nominal size of the rocks is 3 feet. The maximum lift thickness in this case is ___? - ANS 3 feet
@COPYRIGHT ALL RIGHTS RESERVED PAGE 2 OF 9
COMPACTION EXAM REVIEW
QUESTIONS AND ANSWERS 2026
VERIFIED.
T or F - The voids in a saturated soil are partly filled with water and partly filled with air. -
ANS False - They are completely filled with water
What classification system does VDOT use to classify soils? - ANS AASHTO and Unified Soil
Classification System
___ refers to the texture and firmness of a soil - ANS Consistency
Silt and clay are made up of particles that are smaller than the ___ sieve. - ANS No. 200
(75um)
What is the distribution of various particles sizes within the material? - ANS Gradation
___ means that the particles in a mixture are sized so that they fill most of the voids; there is
very little space in between soil or stone particles - ANS Dense graded
What is the moisture content at which a soil begins to behave like a liquid called? -
ANS Liquid Limit
@COPYRIGHT ALL RIGHTS RESERVED PAGE 1 OF 9
, What is the behavior of a material where the material deforms under load and does not go back
to it's original shape called? - ANS Plasticity
What is the moisture content at which a soil can be compacted to its maximum dry density with
the least amount of compactive effort called? - ANS Optimum Moisture Content
T or F - A soil that contains a high percentage of fines is more affected by water than one with a
low percentage of fines - ANS True
T or F - Open graded aggregates are used in a pavement to give the structure more strength -
ANS False - Dense graded aggregates are used in a pavement to give the structure more
strength
T or F - Clearing and Grubbing is required in fill sections less than 5 feet in depth, in borrow
areas before excavation can begin, and in all cut sections. - ANS True
In fill sections where stumps may be left in place, they must be no more than ___ high -
ANS 6 inches
___ means to crown surface of embankment, roll surface of embankment smooth, direct water
to appropriate erosion and siltation controls - ANS Grading to Drain
What is the first lift of embankment material placed in swampy areas called? - ANS Work
Platform
How should layers of embankment material be placed? - ANS Placed with uniform thickness
and parallel to finished grade
Material is being placed 15 feet below the proposed subgrade in a rock fill. The maximum
nominal size of the rocks is 3 feet. The maximum lift thickness in this case is ___? - ANS 3 feet
@COPYRIGHT ALL RIGHTS RESERVED PAGE 2 OF 9
