geo
Soil mechanics is the study of the physical properties and behavior of soil under different conditions. This
branch of civil engineering is essential for understanding how soils will respond to different loads, how
they will consolidate over time, and how they can be effectively compacted.
soil mechanics
Refers to the ability of soil or rock to allow fluids to pass through its pores or
fractures. It's a crucial property for understanding groundwater flow.
permeability
A type of soil composed of both silt and clay particles. This mixture often exhibits
characteristics from both soil types, affecting its plasticity and permeability.
silty clay
The process of increasing the density of soil by mechanically pressing it to reduce air
gaps. Proper compaction is vital in construction to ensure soil stability and strength.
compaction
The process by which soils decrease in volume over time under sustained load,
primarily due to the expulsion of water from pore spaces. This affects settlement rates and must
be considered in design.
consolidation
The maximum load per unit area that the ground can support without excessive
settlement. Ensuring adequate bearing capacity is essential for the stability of structures.
bearing capacity
The ratio of the volume of voids to the volume of solids in a soil sample
void ratio
The percentage of water present in the soil compared to its dry weight.
moisture content
The range of water content where soil exhibits plastic properties, found by
subtracting the plastic limit from the liquid limit.
plasticity index
The water content at which further moisture loss does not cause additional
volume reduction
shrinkage limit
The tendency of soil to increase in volume when it absorbs water, critical for soils
like clays
swell potential
Understanding the properties of soil through testing is essential for predicting how it will behave under
different conditions. These tests help engineers determine the best methods for soil compaction,
foundation design, and more.
soil testing and properties
its maximum density. This test is crucial for construction projects requiring stable
soil foundations.
proctor test
The proportion of different-sized particles in a soil sample, usually
determined through sieve analysis for coarse soils and hydrometer analysis for fine soils. It significantly impacts soil's engineering properties like permeability and shear strength.
grain size distribution
The soil's resistance to shearing forces, which cause layers to slide past one another. It is a key factor in assessing soil stability.
shear strength
A test to determine the size distribution of fine-grained soils by measuring
their settling velocity in water.
hydrometer analysis
A graph that shows the relationship between water content and dry density of
soil. It helps identify the optimum moisture content for maximum soil compaction.
compaction curve
The water content at which soil begins to behave plastically, meaning it can be deformed without cracking.
plastic limit
The water content at which soil transitions from a plastic state to a liquid state
liquid limit
The water content boundaries that define the different states of consistency
for fine-grained soils (solid, plastic, liquid).
atterberg limit
A test that evaluates the strength of subgrade soil and its ability to
support road and pavement structures.
california bearing ratio (cbr)
A test that measures the mechanical properties of soil, including its strength and
cohesion, under different conditions.
triaxial test
Fluid flow through soils, particularly in terms of groundwater movement, is a critical aspect of
geotechnical engineering. The principles of fluid mechanics are used to analyze and predict how water will
move through soil.
fluid flow and hydraulics
Describes the flow of fluid through a porous medium, where flow rate is proportional
to the pressure gradient. It is fundamental to understanding groundwater flow.
darcy's law
The movement of water through soil, which can occur in any direction and is often analyzed using flow nets to prevent soil erosion or failure in structures like dams.
seepage
Fluid movement in parallel layers, with minimal mixing between the layers. This type
of flow is typical in slow-moving, viscous fluids.
laminar flow
A fluid flow regime characterized by chaotic, irregular motion, often resulting in
greater energy loss and mixing.
turbulent flow
The volume of fluid passing through a given area per unit time. It’s a key parameter in
designing systems like drainage and irrigation.
flow rate
The ability of an aquifer to transmit water horizontally, depending on the permeability of the material and the thickness of the aquifer.
transmissivity
An empirical equation used to estimate the hydraulic conductivity of soils based
on grain size distribution.
hazen's formula
Relates the permeability of a porous medium to its porosity and the
specific surface area of the particles.
kazen-carman equation
A graphical tool used to represent the flow of water through soils, showing both flow
lines (paths of water particles) and equipotential lines (lines of constant hydraulic head).
flow net
The stress carried by the soil skeleton, calculated by subtracting pore water
pressure from total stress. It’s crucial for understanding soil strength and stability.
effective stress
These methods and materials are used in the construction and maintenance of soil and rock structures,
ensuring that they are stable, durable, and able to withstand environmental stresses.
geotechnical engineering methods
The controlled use of explosives to break up rock or soil, commonly used in mining and
construction to create foundations or tunnels.
blasting
Material used to refill an excavation, usually to support a structure or restore the original ground level. The choice of backfill material affects the stability of the structure.
backfill
A ground improvement technique that densifies loose, granular soils by using a
vibrating probe. It increases soil strength and decreases settlement.
vibroflotation
A permeable fabric used in civil engineering to improve soil stability, control erosion, and
aid in drainage. Geotextiles are often used in road construction, retaining walls, and landfills
geotextile
: Layers of sedimentary rock or soil with consistent characteristics that distinguish them
from layers above or below. Understanding the strata is crucial for foundation design.
strata
A field test used to determine the relative density and shear
strength of soil. It involves driving a sampler into the ground at the bottom of a borehole and
measuring the resistance.
standard penetration test (spt)
A phenomenon where saturated soil temporarily loses its strength and behaves like a liquid, typically triggered by seismic activity.
soil liquefaction
A synthetic material used to reinforce soils, particularly in retaining walls and roadbeds. It
improves the mechanical properties of the soil.
geogrid
The pressure exerted by water within the soil pores, affecting the soil's
effective stress and overall stability.
pore water pressure
The total load per unit area applied to a soil mass, including both the weight of the
soil particles and the water within the pores.
total stress
These equations are the backbone of civil and geotechnical engineering, providing the mathematical framework for analyzing fluid flow, soil mechanics, and structural stability.
fundamental engineering equations
A principle of fluid dynamics that describes the conservation of energy in a
flowing fluid, combining kinetic energy, potential energy, and fluid pressure.
bernoulli's equation
A procedure used to determine the liquid limit of soils, which helps classify soil
types and predict their behavior under load.
casagrande method
States that the mass flow rate must remain constant from one cross-section
of a fluid flow system to another, fundamental in fluid dynamics.'
continuity equation
A dimensionless number used to predict flow patterns in fluid dynamics,
distinguishing between laminar and turbulent flow.
reynolds number
Used to estimate the velocity of flow in open channels, considering factors like
channel shape, roughness, and slope.
manning's equation
Describes the settling velocities of small spherical particles in a fluid, which is critical in
sedimentation analysis.
stakes' law
A set of nonlinear partial differential equations that describe the motion
of viscous fluid substances, including both liquids and gases
navier-stokes equations