VDOT SOILS AND AGGREGATE
COMPACTION. EXAM QUESTIONS AND
ANSWERS 2026 VERIFIED.
Gravel Sieve - ANS #3-#10
Sand Sieve - ANS #10-#200
Fines Sieve - ANS #200+
Size - ANS Described by particle or grain diameter or average dimension.
Shape - ANS The shape of the grains larger than .06 inches is inditingusable to the naked eye
Surface Texture - ANS Refers to the degree of fineness and uniformity of a soil.
Surface Forces - ANS fine grained platey soils, electrical forces on the surface of the grains.
important of how they react with water
Consistancy - ANS texture and firmness of soil
Cohesion - ANS The mutual attraction of particles due to molecular forces and the present of
moisture films
@COPYRIGHT ALL RIGHTS RESERVED PAGE 1 OF 10
, Sensisitvity - ANS a characteristic of clays that describes the lose of strngth after disturbance
moisture content - ANS how much moisture is in the void spaces
Why are dense grades used more for aggregate bases - ANS bc the dense gradation provides
more strength by filling voids
If the soils is 100 percent saturated and the voids are full of water and has a high MC -
ANS large void spaces and is loosely compacted
If the soils is 100 percent saturated and has low MC - ANS small voids and is compact
in the field: the soil moisture is near the liquid limit - ANS a lot of settlement is likely
in the field: the soil moisture is near the plastic limit - ANS not a lot of settlement is likely
Compaction Percent - ANS (field dry density/ Max Theoretical Density)*100
Does a silty sand or clayey soil require more moisture control - ANS silty sand
What are reasons for unexpected density changes - ANS temp, lift thickness, less than 95
percent compaction, more compactive effort, moisture control, change in material
Bridging vs geofabric - ANS bridging is when you overfill a swampy area to be able to move
across, geofabric is placed between swamp and bridge to keep the moisture out
No slope shall be steeper than what? - ANS 2H:1V
@COPYRIGHT ALL RIGHTS RESERVED PAGE 2 OF 10
COMPACTION. EXAM QUESTIONS AND
ANSWERS 2026 VERIFIED.
Gravel Sieve - ANS #3-#10
Sand Sieve - ANS #10-#200
Fines Sieve - ANS #200+
Size - ANS Described by particle or grain diameter or average dimension.
Shape - ANS The shape of the grains larger than .06 inches is inditingusable to the naked eye
Surface Texture - ANS Refers to the degree of fineness and uniformity of a soil.
Surface Forces - ANS fine grained platey soils, electrical forces on the surface of the grains.
important of how they react with water
Consistancy - ANS texture and firmness of soil
Cohesion - ANS The mutual attraction of particles due to molecular forces and the present of
moisture films
@COPYRIGHT ALL RIGHTS RESERVED PAGE 1 OF 10
, Sensisitvity - ANS a characteristic of clays that describes the lose of strngth after disturbance
moisture content - ANS how much moisture is in the void spaces
Why are dense grades used more for aggregate bases - ANS bc the dense gradation provides
more strength by filling voids
If the soils is 100 percent saturated and the voids are full of water and has a high MC -
ANS large void spaces and is loosely compacted
If the soils is 100 percent saturated and has low MC - ANS small voids and is compact
in the field: the soil moisture is near the liquid limit - ANS a lot of settlement is likely
in the field: the soil moisture is near the plastic limit - ANS not a lot of settlement is likely
Compaction Percent - ANS (field dry density/ Max Theoretical Density)*100
Does a silty sand or clayey soil require more moisture control - ANS silty sand
What are reasons for unexpected density changes - ANS temp, lift thickness, less than 95
percent compaction, more compactive effort, moisture control, change in material
Bridging vs geofabric - ANS bridging is when you overfill a swampy area to be able to move
across, geofabric is placed between swamp and bridge to keep the moisture out
No slope shall be steeper than what? - ANS 2H:1V
@COPYRIGHT ALL RIGHTS RESERVED PAGE 2 OF 10
