Week 3 Soil Properties Flashcards
(21 cards)
What are the three phases of soil?
Solid (soil particles), liquid (water), gas (air)
Soil is not a solid material but a mixture of these three phases.
Who is known as the father of soil mechanics?
Karl von Terzaghi
He made significant contributions to the understanding of soil behavior in engineering.
What is the main focus of the subject area known as ‘soil mechanics’?
Understanding and predicting how soil behaves as an engineering material.
What did Terzaghi publish in 1925?
Fundamental Principles of Earth Mechanics
What is geotechnical engineering?
The branch of civil engineering that involves investigation, assessment, and evaluation of the ground.
List some geotechnical structures designed in geotechnical engineering.
- Foundations
- Excavations
- Retaining walls
- Tunnels
True or False: Soil properties are constant.
False
Soil properties such as stiffness and strength can vary.
What is soil defined as in the engineering context?
Deposits forming part of the Earth’s crust which are not solid rock.
What are common products of rock weathering?
- Quartz (sand)
- Clay minerals
What does particle size distribution indicate?
The range of particle sizes and amount of those particles in a given soil sample.
What is plasticity in soil?
The ability to undergo deformation without cracking, governed by the amount of clay particles.
Fill in the blank: The range known as the ‘Plasticity index’ (PI) is between the _______ and Liquid Limit.
Plastic Limit
What does a plasticity chart plot?
A soil’s Plasticity Index against its Liquid Limit.
What terminology is used to describe soil?
Standard terminology as per BS5930 to define the soil type and basic characteristics.
Which property of soil is affected by moisture content?
Stiffness
What is void ratio important for?
Consolidation calculations.
List some properties that can be determined from the phase relationship of soil.
- Moisture content
- Void ratio
- Density
What is porosity?
The ratio of the volume of voids to the total volume of the sample.
What is bulk density?
Total mass / total volume
What does specific gravity indicate?
Density of soil / density of water
What is the degree of saturation?
Proportion of voids filled with water.
