Download Atkinson J., Fundamentals of Ground Engineering, 2014 PDF

TitleAtkinson J., Fundamentals of Ground Engineering, 2014
TagsGeotechnical Engineering Rock (Geology) Sedimentary Rock Geology
File Size2.8 MB
Total Pages244
Table of Contents
                            Front Cover
Contents
Geology and Engineering
How to Use This Book
Things to Do
Further Reading
Acknowledgements
Units
Symbols
Chapter 1: What is Geotechnical Engineering?
Part A: Discovering the Ground
	Chapter 2: Formation of Soils and Rocks
	Chapter 3: Description and Classification of Soils
	Chapter 4: Ground Investigations
Part B: Essential Physics and Mechanics
	Chapter 5: A Little Basic Mechanics
	Chapter 6: Behaviour of Materials
	Chapter 7: Water Pressure and Seepage
Part C: Soil Mechanics
	Chapter 8: Pore Pressure and Effective Stress
	Chapter 9: Soil Behaviour Observed in Tests on Samples
	Chapter 10: Soil Deformation
	Chapter 11: Soil Strength
	Chapter 12: State and State Parameters
	Chapter 13: Cam Clay and Numerical Modelling
	Chapter 14: Soil Parameters for Design
Part D: Geotechnical Engineering
	Chapter 15: Routine Analyses of Geotechnical Structures
	Chapter 16: Stability of Slopes
	Chapter 17: Foundations
	Chapter 18: Retaining Walls
	Chapter 19: Unsaturated, Improved and Difficult Soils
	Chapter 20: Principles of Geotechnical Design
Keywords, Definitions and Index
                        
Document Text Contents
Page 1

Fundamentals of
Ground Engineering

John Atkinson

A S P O N P R E S S B O O K

Geotechnical Engineering

“The book is a unique introduction for those starting a career in ground
engineering and for professionals … who have not specialized in the area.
The subject matter is presented in a beautifully clear, simple and integrated
manner, as one would expect from the author.”

—David Hight, Geotechnical Consulting Group, London, UK

“I like the book so much because it covers the complete range of
geotechnical engineering … from underlying principles to the design of
all major geotechnical constructions. This book is a perfect companion
for those learning the subject for the first time … and also a nice tool for
practical engineers.”

—Tom Schanz, Ruhr-Universität Bochum, Germany

“The author’s insistence on the critical importance of understanding …
fundamentals is something that all practitioners, and indeed all geotechnical
professionals, should heed.”

—Harry Poulos, Coffey Geotechnics, Australia

“This book … is not just another book on soil mechanics, but well distilled
knowledge of the subject presented to create maximum visual impact.”

—Gopal Madabhushi, University of Cambridge, UK

Fundamentals of Ground Engineering puts the mechanics into soil
mechanics. It contains brief—one or two pages per topic—summaries
of the key principles, theories, definitions and analyses of geotechnical
engineering. It will be used by students, practicing civil engineers—senior
and junior—and by engineering geologists as a short easily read summary
and as a guide to further study.

John Atkinson is Emeritus Professor of Soil Mechanics at City University,
London and Senior Principal with Coffey Geotechnics. He has long
experience of teaching soil mechanics and geotechnical engineering
to students and practicing engineers and is an author of previous
text-books.

K21495

John Atkinson

Page 2

Fundamentals of

Ground Engineering

Page 122

99

Soil Deformation

10.7 very sMall strain stiffness G′0

The very small strain shear modulus G′0 is related to the velocity Vs of a shear wave and the unit
weight of the soil γ by

G’
V
g

s
0

2

=
γ

Vs is relatively easy to measure in laboratory tests or in the ground.

Shear waves generated at ground level or at
depth.

Vibrating bender elements in the top and
bottom of a triaxial sample.

Down hole

Cross hole

For a particular soil G′0 depends on the current mean stress p′ and on the current state. Typical
values range from 20 MPa for soft soil to over 100 MPa for stiff soils.

G′0 is an important soil stiffness parameter. It can be measured in situ or in laboratory tests and
it ‘anchors’ the stiffness decay curve at the very small strain end.

Page 123

100

Fundamentals of Ground Engineering

10.8 Consolidation

When a total stress Δσv is applied quickly fine-grained soil is undrained. Because Δεv = 0 and
Δσ′v = 0 pore pressure will increase by Δu = Δσv and this is the initial excess pore pressure u0.

As time passes the excess pore pressures dissipate with constant total stress as water flows
towards a drain where u=0 and the soil compresses. This is consolidation.

After a long time excess pore pressures become u=0. From the start to the finish of consolida-
tion ∆σ ∆ ∆σ′ = =v vu .

Excess pore pressure in 1D consolidation

t1

t2

a

b

c

d

Drainage

t0; u0 = ∆u = ∆σv

t∞; u∞ = 0





∆σv

a

a

b

b

t1

t2

t2t1 tt0

t∞

t∞

t0

u0 u

c

c

d

d

u







The base and sides of the container are
impermeable so water can only drain upwards
so drainage and deformations are 1D.

At time t0 there is an excess pore pressure u0
everywhere as shown by the rise of water in
the standpipes.

The excess pore pressure u at any depth
decays with time. After a very long time
u∞ = 0 everywhere.

At any point in the ground δσ δ′ = u during an
interval of time δt.

Excess pore pressures decay at different rates
at different depths depending on the distances
from the drainage surface. The pore pressure
at a point near the surface decays very quickly;
lower down pore pressures do not start to
decay immediately.

Page 243

220

Fundamentals of Ground Engineering

Term Definition Section

Water pressures on
retaining walls

Pore water and free water apply loads to
walls; pore water influences effective earth
pressures.

18.7

Water table Surface in the ground joining all points
where u = 0. If the water table is level the
groundwater is hydrostatic and there is no
seepage.

7.1

Wet of optimum Compaction at a water content greater than
the optimum water content.

19.1

Wet side of critical States that have water contents larger than
the critical water content at the same
effective stress. This is not the same as wet
of optimum (Section 19.1).

12.3

Worst credible value It is unreasonable to assume a value for
design worse than this.

14.5

Yield A state at which behaviour changes from
elastic to plastic or elasto-plastic.

6.6, 6.7, 13.2

Yield stress ratio Ry
y=




σ
σ

1 10.2

Young’s modulus ′ =E
q
a

δ
δε 10.1

Page 244

Fundamentals of
Ground Engineering

John Atkinson

A S P O N P R E S S B O O K

Geotechnical Engineering

“The book is a unique introduction for those starting a career in ground
engineering and for professionals … who have not specialized in the area.
The subject matter is presented in a beautifully clear, simple and integrated
manner, as one would expect from the author.”

—David Hight, Geotechnical Consulting Group, London, UK

“I like the book so much because it covers the complete range of
geotechnical engineering … from underlying principles to the design of
all major geotechnical constructions. This book is a perfect companion
for those learning the subject for the first time … and also a nice tool for
practical engineers.”

—Tom Schanz, Ruhr-Universität Bochum, Germany

“The author’s insistence on the critical importance of understanding …
fundamentals is something that all practitioners, and indeed all geotechnical
professionals, should heed.”

—Harry Poulos, Coffey Geotechnics, Australia

“This book … is not just another book on soil mechanics, but well distilled
knowledge of the subject presented to create maximum visual impact.”

—Gopal Madabhushi, University of Cambridge, UK

Fundamentals of Ground Engineering puts the mechanics into soil
mechanics. It contains brief—one or two pages per topic—summaries
of the key principles, theories, definitions and analyses of geotechnical
engineering. It will be used by students, practicing civil engineers—senior
and junior—and by engineering geologists as a short easily read summary
and as a guide to further study.

John Atkinson is Emeritus Professor of Soil Mechanics at City University,
London and Senior Principal with Coffey Geotechnics. He has long
experience of teaching soil mechanics and geotechnical engineering
to students and practicing engineers and is an author of previous
text-books.

K21495

John Atkinson

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