Introduction to Foundation Engineering

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SYLLABUS of FOUNDATION
ENGINEERING
Soil Exploration
Shallow Foundations
Deep Foundations
Earthen Dams

SYLLABUS of FOUNDATION
ENGINEERING
Soil Exploration
Importance of soil exploration and planning of soil
exploration program. Soil exploration methods:
probing, test pits, auger boring, wash boring,
percussion and rotary drilling and geophysical
methods. Disturbed and undisturbed soil
sampling. Soil samplers. Insitu tests: standard
penetration test (SPT), cone penetration test
(CPT), plate load test and field vane shear test.
Bore hole logs and subsoil exploration report.

Foundations
Definition, purpose and types of and general
requirements of foundations. Depth of
footings. Selection of foundation type.
Shallow Foundations
Definition of bearing capacity. Methods of
determining bearing capacity. Presumptive
values of bearing capacity. Terzaghi and
Meyerhof’s theories of bearing capacity and
design of isolated, combined and strip
footings. Settlement of shallow foundations
and their remedial measures.

Deep Foundations
Introduction to deep foundations. Types of
piles. Load carrying capacity of piles. Group
action. Settlement. Negative skin friction. Pile
load test. Cassion and well foundations.
Earthen Dams
Types of earthen dams, components and their
functions. General design considerations and
typical cross- section.
Foundations on difficult soils
Intoduction to relevant softwares.

Text
Principles of
Foundation
Engineering
by Braja M.
Das

Reference
Soil
Mechanics &
Foundations
by Muni
Budhu

Reference
Foundation
Analysis
and Design
by Joseph E. Bowles

Reference
Foundation
Design
by Donald
P. Coduto

Definition
Foundation is a part of the structure that
supports the structural weight and transmits
the load to underlying soil or rock.(Foundation
includes foundation structure and soil
influenced by the structural load.)

Types of Foundations
Shallow Foundations versus Deep
Foundations
Foundations
Shallow
Foundations
Deep
Foundations
Spread
Footings
Mat
Foundations
Driven
Piles
Drilled
Shafts
Auger Cast
Piles

Foundations
Shallow Footings
Spread Footing
Mat Footing Combined Footing

Deep Foundation

Shoes, Snow shoes, and stilts are much like
the different types of footings of a structure
A Shoe make contact with a firm
surface (spread footings)
B. Snow shoes spread weight
over a large surface (raft footing).
C. Stilts (pile footings)
reach firm surface

Parts of a Foundation
A foundation (substructure) can
be divided into three parts
Bearing surface.
Footing.
Upright supports.
The bearing surface is the
earth upon which the
foundation rests. It may be soil
or bedrock. The bearing surface
may be far below the surface of
a swamp, river, or ocean.

The footing is the flat part of the foundation.
It spreads the load of the structure above it.
Upright support. They may be walls or
piers (masonry column) that rise above the
footing. They form the rest of the structure.

Foundation System
This part will be done
by the Structural
Engineer

Every civil engineering structure such as :
Buildings
Bridges.
Highway pavement ,and
Railway track
Will have a superstructure and
substructure(Foundations)

Super structure transmits the load.
Sub structure receives and transmits the
load to underlying soil or rock.
The foundation engineer’s aim is that no
component of the structure and foundation
should experience of any kind of distress.
Geotechnical design parameters:
- Bearing capacity
- Settlement

What is Foundation Engineering?
The art of selecting, designing, and constructing
structural support systems based on scientific
principles of soils and engineering mechanics
incorporating accumulated experience with
such applications.

What is the current
state-of-the-art?
In spite of the many advances in foundation
engineering it is still an art mostly supported
by empirical techniques.

Why mostly empirical?
We do not fully understand the
behavior of foundations.
Knowledge of subsurface conditions
are always limited.

What do I have to know to be a
good Foundation Engineer?
Geology
Geophysics
Subsurface Exploration
Laboratory Testing
Soil Mechanics
Structural Engineering
Construction Engineering

Uncertainties
Soils:
Not a manufactured material
High degree of variability
Material characterization done based
on a small sample
Complex behavior (non-linear;
anisotropic)
Rationalism vs. Empiricism
Factors of Safety

Who is responsible for
uncertainties?
You (the Foundation Engineer).
Always use presence, common sense
engineering, and experience first, beforefirst, beforefirst, beforefirst, before
blindly following analysis and test results.

What is analysis good for?
It is good to confirm that a
precedent solution can be safely
applied to your site.

What makes a good
foundation?
Safe
Reliable
Durable
Buildable
Economical

Is it my job to be concerned of
costs?
Yes. As a professional engineer, it is your
obligation to balance “costs and
uncertainties

The Final Question
In Foundation Engineering, there areIn Foundation Engineering, there areIn Foundation Engineering, there areIn Foundation Engineering, there are
manymanymanymany ““““ifififif’’’’ssss”””” andandandand ““““butbutbutbut’’’’ssss””””. What do I do. What do I do. What do I do. What do I do
when I am in doubt?when I am in doubt?when I am in doubt?when I am in doubt?
1. When in doubt go wide.
2. When in doubt go deep.
3. When in doubt grout (ground modify).

Eiffel Tower, Paris, France,
built in 1887-1889

Leaning Tower, Pisa, Italy
Built 1173-1350

Palacio de las Bellas
Artes, Mexico City
Built 1932-1934

Tower of Latino
Americana, Mexico City
Built in 1956
44 stories; 597-ft

Performance Requirements
Design Loads
Allowable Stress Design vs LRFD
Performance Requirements
Strength Requirements
Serviceability Requirements
Total Settlement
Differential Settlement
Constructability Requirements
Economic Requirements

Strength Requirements
Foundation
soil must be
strong
enough to
support
imposed
loads …..

Failure of a Bridge Foundation

Serviceability Requirements
Settlement must
be within
acceptable limits
…..

Total vs. Differential Settlement

Geotechnical Aspects
Determining the type of foundation for the structure,Determining the type of foundation for the structure,Determining the type of foundation for the structure,Determining the type of foundation for the structure,
including the depth and dimensionsincluding the depth and dimensionsincluding the depth and dimensionsincluding the depth and dimensions
Calculating the potential settlement of the foundationCalculating the potential settlement of the foundationCalculating the potential settlement of the foundationCalculating the potential settlement of the foundation
Determining the expansion potentialDetermining the expansion potentialDetermining the expansion potentialDetermining the expansion potential
Investigating the stability of slopes and their effect onInvestigating the stability of slopes and their effect onInvestigating the stability of slopes and their effect onInvestigating the stability of slopes and their effect on
adjacent foundationsadjacent foundationsadjacent foundationsadjacent foundations
Investigating the possibility of foundation movementInvestigating the possibility of foundation movementInvestigating the possibility of foundation movementInvestigating the possibility of foundation movement
due to seismic forces, which would also include thedue to seismic forces, which would also include thedue to seismic forces, which would also include thedue to seismic forces, which would also include the
possibility of liquefactionpossibility of liquefactionpossibility of liquefactionpossibility of liquefaction

Performing studies and tests to determine the potentialPerforming studies and tests to determine the potentialPerforming studies and tests to determine the potentialPerforming studies and tests to determine the potential
for deterioration of the foundationsfor deterioration of the foundationsfor deterioration of the foundationsfor deterioration of the foundations
Evaluating possible soil treatment to increase theEvaluating possible soil treatment to increase theEvaluating possible soil treatment to increase theEvaluating possible soil treatment to increase the
foundation bearing capacityfoundation bearing capacityfoundation bearing capacityfoundation bearing capacity
Determining design parameters for retaining wallDetermining design parameters for retaining wallDetermining design parameters for retaining wallDetermining design parameters for retaining wall
foundationsfoundationsfoundationsfoundations
Providing recommendations for dewatering andProviding recommendations for dewatering andProviding recommendations for dewatering andProviding recommendations for dewatering and
drainage of excavations needed for the construction ofdrainage of excavations needed for the construction ofdrainage of excavations needed for the construction ofdrainage of excavations needed for the construction of
the foundationthe foundationthe foundationthe foundation

Investigating ground water and seepage problems andInvestigating ground water and seepage problems andInvestigating ground water and seepage problems andInvestigating ground water and seepage problems and
developing mitigation measures during foundationdeveloping mitigation measures during foundationdeveloping mitigation measures during foundationdeveloping mitigation measures during foundation
constructionconstructionconstructionconstruction
Site preparation, including compaction specificationsSite preparation, including compaction specificationsSite preparation, including compaction specificationsSite preparation, including compaction specifications
and density testing during gradingand density testing during gradingand density testing during gradingand density testing during grading
Underpinning and field testing of foundationsUnderpinning and field testing of foundationsUnderpinning and field testing of foundationsUnderpinning and field testing of foundations

General Requirements for
Foundation Engineering Projects
Knowledge of the general topography of the siteKnowledge of the general topography of the siteKnowledge of the general topography of the siteKnowledge of the general topography of the site
The location of buried utilitiesThe location of buried utilitiesThe location of buried utilitiesThe location of buried utilities
The geology of the proposed siteThe geology of the proposed siteThe geology of the proposed siteThe geology of the proposed site
The previous history and use of the siteThe previous history and use of the siteThe previous history and use of the siteThe previous history and use of the site
Any special features such as the possibility ofAny special features such as the possibility ofAny special features such as the possibility ofAny special features such as the possibility of
earthquakes or climate factors such as flooding ,earthquakes or climate factors such as flooding ,earthquakes or climate factors such as flooding ,earthquakes or climate factors such as flooding ,
seasonal swelling and shrinkage, permafrost, or soilseasonal swelling and shrinkage, permafrost, or soilseasonal swelling and shrinkage, permafrost, or soilseasonal swelling and shrinkage, permafrost, or soil
erosionerosionerosionerosion

The availability and quality of local construction materialsThe availability and quality of local construction materialsThe availability and quality of local construction materialsThe availability and quality of local construction materials
For maritime or river structures, information on tidal rangesFor maritime or river structures, information on tidal rangesFor maritime or river structures, information on tidal rangesFor maritime or river structures, information on tidal ranges
and river levels, velocity of tidal and river currents, andand river levels, velocity of tidal and river currents, andand river levels, velocity of tidal and river currents, andand river levels, velocity of tidal and river currents, and otherotherotherother
hydrographic and meteorological datahydrographic and meteorological datahydrographic and meteorological datahydrographic and meteorological data
A detailed record of the soil and rock strata and ground waterA detailed record of the soil and rock strata and ground waterA detailed record of the soil and rock strata and ground waterA detailed record of the soil and rock strata and ground water
conditions within the zones affected by foundation bearingconditions within the zones affected by foundation bearingconditions within the zones affected by foundation bearingconditions within the zones affected by foundation bearing
pressure and construction operationspressure and construction operationspressure and construction operationspressure and construction operations

Results of laboratory tests on soil andResults of laboratory tests on soil andResults of laboratory tests on soil andResults of laboratory tests on soil and
rock samples appropriate to therock samples appropriate to therock samples appropriate to therock samples appropriate to the
particular foundation design orparticular foundation design orparticular foundation design orparticular foundation design or
construction problemsconstruction problemsconstruction problemsconstruction problems
Results of chemical analyses on soil andResults of chemical analyses on soil andResults of chemical analyses on soil andResults of chemical analyses on soil and
ground water to determine possibleground water to determine possibleground water to determine possibleground water to determine possible
deleterious of foundation structuresdeleterious of foundation structuresdeleterious of foundation structuresdeleterious of foundation structures

Preliminary Information and Planning
the Work
Project LocationProject LocationProject LocationProject Location
Basic information on the location of the project is
required. The location of the project can be compared
with known geological hazards such as active faults,
landslides, or deposits prone to liquefaction.
Type of ProjectType of ProjectType of ProjectType of Project
It is important to obtain as much information about the
project as possible.

Such information could include the type of structure and use,
size of the structure including the number of stories, type of
construction and floor systems, preliminary foundation type,
and estimated structural loadings.
Scope of workScope of workScope of workScope of work
The scope of the work must be determined, which includes
subsurface exploration and laboratory testing to determine
the feasibility of the project, the preparation of foundation
design parameters, and compaction testing during the grading
of the site in order to prepare the building pad for foundation
construction.

After the preliminary information is obtained, the next
step is to plan the foundation investigation work.
For minor project, the planning effort may be minimal,
but for large-scale projects, the plan could be quite
extensive and could change as the design and
construction progresses.

The planning effort could include the following:
Budget and scheduling considerations
Selection of a team of professionals of relevant fields
(such as geotechnical engineer, engineering geologist,
structural engineer, hydro geologist and the like)that will
work on the project
Preliminary subsurface exploration plan, such as number
, location, and depth of borings

Document collection
Laboratory testing requirements
Types of engineering analyses
that will be required for the design
of the foundation.

Introduction to Foundation Engineering

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