CLARB Soils and Geology 2

Question 1

Which ASTM standard governs the Standard Proctor compaction test used to determine optimal moisture content for maximum dry density?

Accepted Answer

ASTM D698

Answer

ASTM D1557

Answer

ASTM D2216

Answer

ASTM D4318

Question 2

Which soil condition presents the greatest risk for building foundations and hardscape due to volumetric changes with moisture fluctuations?

Accepted Answer

Expansive clay soils

Answer

Sandy soils

Answer

Gravelly soils

Answer

Organic peat soils

Question 3

The angle of repose is a critical soil engineering property that most directly influences which landscape design consideration?

Accepted Answer

Slope stability and cut/fill grading design

Answer

Irrigation system design

Answer

Plant species selection

Answer

Drainage pipe sizing

Question 4

What does soil bearing capacity describe in the context of landscape construction?

Accepted Answer

The maximum load per unit area soil can support without failure or excessive settlement

Answer

The soil's ability to retain water between irrigation cycles

Answer

The amount of organic amendments soil can incorporate

Answer

The soil's resistance to erosion from surface runoff

Question 5

Liquefaction — where saturated soil temporarily loses strength and behaves like a liquid — is most commonly triggered by which event?

Accepted Answer

Seismic (earthquake) activity

Answer

Heavy sustained rainfall

Answer

Prolonged drought followed by irrigation

Answer

Repeated freeze-thaw cycles

Question 6

What is the primary purpose of conducting a soil percolation test on a landscape site?

Accepted Answer

Measuring the rate at which soil absorbs water for drainage or infiltration system design

Answer

Determining soil pH and fertility levels

Answer

Assessing the structural bearing capacity of native soils

Answer

Evaluating soil compaction using penetration resistance

Question 7

Which phenomenon occurs when soil consolidates vertically under the weight of overlying fill or structures over time?

Accepted Answer

Settlement/consolidation

Answer

Liquefaction

Answer

Compaction

Answer

Frost heave