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1. What is the primary purpose of soil classification in geotechnical
engineering?
A. To determine soil color for aesthetic reporting
B. To group soils based on engineering behavior and properties
C. To measure soil temperature variations
D. To estimate soil biological activity
B To group soils based on engineering behavior and properties
Soil classification is used to organize soils into groups with similar
engineering characteristics to aid in design, analysis, and
construction decisions.
2. Which soil particle size is classified as clay according to the Unified Soil
Classification System (USCS)?
, A. 4.75 mm to 75 mm
B. 0.075 mm to 4.75 mm
C. Less than 0.002 mm
D. 0.002 mm to 0.05 mm
C Less than 0.002 mm
Clay particles are the smallest soil fraction and exhibit high plasticity
and cohesion due to their microscopic size and mineral composition.
3. What laboratory test is primarily used to determine soil moisture
content?
A. Proctor test
B. Atterberg limits test
C. Oven-drying method
D. Direct shear test
C Oven-drying method
The oven-drying method is the standard procedure for measuring
water content by comparing wet and dry soil mass.
4. The liquid limit of soil is defined as the moisture content at which soil:
A. Becomes brittle
B. Transitions from plastic to liquid state
C. Becomes fully dry
D. Loses all cohesion
B Transitions from plastic to liquid state
, The liquid limit marks the boundary between plastic and liquid
behavior of fine-grained soils.
5. Which device is commonly used to determine soil compaction in the
field?
A. Hydrometer
B. Nuclear density gauge
C. Pycnometer
D. Sieve shaker
B Nuclear density gauge
A nuclear density gauge provides rapid field measurements of soil
density and moisture content for compaction quality control.
6. What is the main objective of the Proctor compaction test?
A. To determine shear strength
B. To identify soil minerals
C. To establish optimum moisture content and maximum dry density
D. To measure permeability
C To establish optimum moisture content and maximum dry density
The Proctor test determines the relationship between moisture
content and dry density for compaction control.
7. Soil permeability refers to:
A. Soil resistance to erosion
B. Ability of soil to transmit water
C. Soil color variation
, D. Soil compressibility under load
B Ability of soil to transmit water
Permeability describes how easily water flows through soil void
spaces.
8. Which soil type typically has the highest permeability?
A. Clay
B. Silt
C. Gravel
D. Organic soil
C Gravel
Gravel has large void spaces allowing rapid water movement,
making it highly permeable.
9. The Atterberg limits are used primarily for:
A. Determining soil strength
B. Classifying fine-grained soils
C. Measuring particle size distribution
D. Testing soil permeability
B Classifying fine-grained soils
Atterberg limits define consistency limits of fine soils based on
moisture content changes.
10. What is the plastic limit of soil?
A. Moisture content where soil becomes liquid
B. Moisture content where soil crumbles when rolled into threads