ICC SOILS CARDS STUDY GUIDE 2026
VERIFIED QUESTIONS AND SOLUTIONS
◉ The 5 Types of soils are...
Answer: Gravel (mm to cm's in size)
Sand (mm in size)
Silt (fine particles with little cohesion)
Clay (has cohesion, can stick together)
Organic soils (peat, topsoil)
◉ Define Organic soils (O)
Answer: Have a large componet of dead or decaying plants, and are
not used in construction
◉ How are Silt and Clay classified?
Answer: Classified based on whether the soil is plastic or non-plastic
(eg. can you roll it into a ball)
◉ How are Gravel and Sand classified?
,Answer: are classified based on whether or not all the particle are
roughly the same size(uniform, like a beach) or if there is large
variety in particle size (well-graded)
◉ Soil layers
Answer: 1. (complex zone) 3 to 4m
2. (glacio-lacustrine clay) 2-12m
3. Glacial till, up to 9m in thickness
4. Carbonate bedrock, the upper surface of which is often fractured,
weathers and irrgular
◉ What are the 2 components of Soil strength?
Answer: Cohesion (clay only)
Friction (when individual soil grains move across on another)
◉ Soil fail by
Answer: shear
◉ Soil strength is used to determine which 2 things?
Answer: The bearing capacity of a foundation
The stability of natural or man-made earth slopes or retaining walls
,◉ Tests for soil strength include;
Answer: unconfined compression test
direct shear test
Triaxial compression
◉ Soil strength depends upon
Answer: Density and moisture content
◉ Unconfined compression test is for what?
Answer: useful for comparing strength of two soils or varion of
strength with dept.
◉ Gradation refers to the range of measured soil particle sizes.
Gradation results in classifying soil as?
Answer: Gravel ( > 2 mm)
Sand (between 0.075 and 2 mm)
Silt (0.002 to 0.075 mm)
Clay (< 0.002 mm)
◉ The particle size distribution of coarse-grained soils is typically
determined by?
Answer: Mechanical sieve analysis
, ◉ The particle size distribution of fine-grained soil is determined
using a ?
Answer: hydrometer analysis
◉ Two parameters help to identify soils that are well-graded?
Answer: The Coefficient of Uniformity (Cu)
The Coefficient of Curvature (Cc)
◉ The hydrometer analysis is used to determine the gradation of
Answer: slit and clay-sized particles.
◉ Only soil particles passing the No. 40 sieve(0.425) are used in the
Answer: hydrometer analysis
◉ Hydrometer readings give us two things?
Answer: The specific gravity, or density, of the fluid tells us the % of
material is still in suspension.
The average downward velosity of the hydrometer can give us the
diameter of the particle hat is just coming out of solution.
VERIFIED QUESTIONS AND SOLUTIONS
◉ The 5 Types of soils are...
Answer: Gravel (mm to cm's in size)
Sand (mm in size)
Silt (fine particles with little cohesion)
Clay (has cohesion, can stick together)
Organic soils (peat, topsoil)
◉ Define Organic soils (O)
Answer: Have a large componet of dead or decaying plants, and are
not used in construction
◉ How are Silt and Clay classified?
Answer: Classified based on whether the soil is plastic or non-plastic
(eg. can you roll it into a ball)
◉ How are Gravel and Sand classified?
,Answer: are classified based on whether or not all the particle are
roughly the same size(uniform, like a beach) or if there is large
variety in particle size (well-graded)
◉ Soil layers
Answer: 1. (complex zone) 3 to 4m
2. (glacio-lacustrine clay) 2-12m
3. Glacial till, up to 9m in thickness
4. Carbonate bedrock, the upper surface of which is often fractured,
weathers and irrgular
◉ What are the 2 components of Soil strength?
Answer: Cohesion (clay only)
Friction (when individual soil grains move across on another)
◉ Soil fail by
Answer: shear
◉ Soil strength is used to determine which 2 things?
Answer: The bearing capacity of a foundation
The stability of natural or man-made earth slopes or retaining walls
,◉ Tests for soil strength include;
Answer: unconfined compression test
direct shear test
Triaxial compression
◉ Soil strength depends upon
Answer: Density and moisture content
◉ Unconfined compression test is for what?
Answer: useful for comparing strength of two soils or varion of
strength with dept.
◉ Gradation refers to the range of measured soil particle sizes.
Gradation results in classifying soil as?
Answer: Gravel ( > 2 mm)
Sand (between 0.075 and 2 mm)
Silt (0.002 to 0.075 mm)
Clay (< 0.002 mm)
◉ The particle size distribution of coarse-grained soils is typically
determined by?
Answer: Mechanical sieve analysis
, ◉ The particle size distribution of fine-grained soil is determined
using a ?
Answer: hydrometer analysis
◉ Two parameters help to identify soils that are well-graded?
Answer: The Coefficient of Uniformity (Cu)
The Coefficient of Curvature (Cc)
◉ The hydrometer analysis is used to determine the gradation of
Answer: slit and clay-sized particles.
◉ Only soil particles passing the No. 40 sieve(0.425) are used in the
Answer: hydrometer analysis
◉ Hydrometer readings give us two things?
Answer: The specific gravity, or density, of the fluid tells us the % of
material is still in suspension.
The average downward velosity of the hydrometer can give us the
diameter of the particle hat is just coming out of solution.
