Soils and rocks have unique and distinct engineering properties.
Engineering properties of soils and rocks are very essential parameters to be analysed for several technical reasons.
Properties of these materials may not only pose problems but also give solutions to solve the problems.
Soils and rocks have unique and distinct engineering properties.
Engineering properties of soils and rocks are very essential parameters to be analysed for several technical reasons.
Properties of these materials may not only pose problems but also give solutions to solve the problems.
index properties of soil, Those properties of soil which are used in the identification and classification of soil are known as INDEX PROPERTIES
Water content
Specific gravity
In-situ density
Particle size
Consistency
Relative Density
This presentation is all about Shear Strength of Soil and it's importance in Civil Engineering, application of shear strength, direct shear test, mohr's circle, mohr's coulomb, shear strength, triaxial shear test, unconfined compression test, vane shear test
Bearing capacity of shallow foundations by abhishek sharma ABHISHEK SHARMA
elements you should know about bearing capacity of shallow foundations are included in it. various indian standards are also used. Bearing capacity theories by various researchers are also included. numericals from GATE CE and ESE CE are also included.
This presentation includes Definition of Permeability, measurement of Permeability, Validity of Darcy's law, Darcy's Law, Methods of Finding Permeability, factors affecting permeability, Permeability of Stratified Soil
Class notes of Geotechnical Engineering course I used to teach at UET Lahore. Feel free to download the slide show.
Anyone looking to modify these files and use them for their own teaching purposes can contact me directly to get hold of editable version.
index properties of soil, Those properties of soil which are used in the identification and classification of soil are known as INDEX PROPERTIES
Water content
Specific gravity
In-situ density
Particle size
Consistency
Relative Density
This presentation is all about Shear Strength of Soil and it's importance in Civil Engineering, application of shear strength, direct shear test, mohr's circle, mohr's coulomb, shear strength, triaxial shear test, unconfined compression test, vane shear test
Bearing capacity of shallow foundations by abhishek sharma ABHISHEK SHARMA
elements you should know about bearing capacity of shallow foundations are included in it. various indian standards are also used. Bearing capacity theories by various researchers are also included. numericals from GATE CE and ESE CE are also included.
This presentation includes Definition of Permeability, measurement of Permeability, Validity of Darcy's law, Darcy's Law, Methods of Finding Permeability, factors affecting permeability, Permeability of Stratified Soil
Class notes of Geotechnical Engineering course I used to teach at UET Lahore. Feel free to download the slide show.
Anyone looking to modify these files and use them for their own teaching purposes can contact me directly to get hold of editable version.
Diagrid structural systems
are emerging as structurally efficient as well as architecturally significant assemblies for tall buildings.
. The evolution of tall building structural systems based on new structural
concepts with newly adopted high strength materials and construction methods have been towards “stiffness” and “lightness”. Structural systems are become
“lighter” and “stiffer”.
It is common knowledge that rather than directly standing the forces,
it is better to reduce them and dissipate the magnitude of vibrations.
Structure design of high rise buildings is governed by lateral loads due to
wind or earthquake.
Lateral load resistance of structure is provided by interior structural system
or exterior structural system.
The selected structural system should be such that it should be effectively
utilized for structural requirements.
Recently diagrid structural system is adopted in tall buildings due to its
structural efficiency and flexibility in architectural planning.
Prepared by madam rafia firdous. She is a lecturer and instructor in subject of Plain and Reinforcement concrete at University of South Asia LAHORE,PAKISTAN.
Effect of CO2 sequestration on soil liquefaction in geological pitsijiert bestjournal
This paper deals with review of the previous related research on evaluation of soil liquefaction due to Carbon sequestration by various Carbon Capture Sequestration processes in geological pits. It provides critical literature recommendations on evaluation of soil liqu efaction potential assessment. The detection of soil liquefaction by using seismic records has been developed by various researchers. With this information,the evaluation of soil liquefaction are well under stood and this lead to a more precise and confident output. Gaining support for CCS will require engaging the interest and building the support of a variety of stakeholders,each with differ ent perspectives and goals. Although,CCS builds upon a technology base developed over more than half a century by the oil and gas industry. In the past,the industrially released CO 2 had been introduced to ocean which was harming the aquatic animals. In view of this,the sequestration of CO 2 into ocean was internationally banned. Hence,now much of the Carbon sequestration process is done by various industries in geolog ical pits. This creates a major threat to the earth quake problems worldwide. With the enhanced frequenc y of earthquakes all around the world,it is presumed by many environment scientists that the CO 2 sequestration pits leads to soil liquefaction and hence it results in more frequent earth quakes. T herefore,this paper summarises,different methods to evaluate liquefaction potential of soil by usi ng studies from seismic waves generated in earth,it is also propose it is also explains different me thodology for an eco friendly technology to reduce CO 2 from environment.
Soil mechanics is a branch of soil physics and applied mechanics that describes the behavior of soils. ... Soil mechanics is used to analyze the deformations of and flow of fluids within natural and man-made structures that are supported on or made of soil, or structures that are buried in soils.
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They provide a major part of the information required for
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essential for interpreting soils and for coordinating
interpretations across state and regional boundaries. The soil
descriptions and the soil map are very useful tools for developing a region in various sectors. For all applications, soil profile is the basic aspect to be understood. This module highlights the details of a soil profile.
Effects of Soil and Air Drying Methods on Soil Plasticity of Different Cities...IJERA Editor
Atterberg Limits were initially defined in 1911, by Albert Atterberg, a Swedish scientist. Their purposes are to classifying cohesive soils and determine engineering properties of soils. According to ASTM, all the soils tested by Atterberg limits should be oven dried, it is because drying the soils in different degree will alter their properties significantly. Some of the physical properties of soils will undergo changes that appear to be permanent. Therefore, the soil samples should be in natural or air-dried form. However, in reality, due to time constraint and other factors, many will run the tests by using soil samples that are prepared by oven drying method. They assumed that there is no difference between the results of two types of drying method. However, in reality, the properties of soil will be affected and thus give a misleading result. The objective of this study is to determine the effect of two drying methods, air-drying method and oven drying method, on the soil plasticity. Six soil samples from different cities were tested. These tests include sieve analysis, specific gravity test, hydrometer analysis, Plastic limit and liquid limit test. Conclusively, the oven drying method could not replace the air-drying method in soil preparation for both Atterberg limits tests.
I upload this PPT because I want to say thankfully my group that do the best and hardest to make it very good, especially my group leader!!!
The last one I want to say thank for viewing and downloading.
We have compiled the most important slides from each speaker's presentation. This year’s compilation, available for free, captures the key insights and contributions shared during the DfMAy 2024 conference.
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NUMERICAL SIMULATIONS OF HEAT AND MASS TRANSFER IN CONDENSING HEAT EXCHANGERS...ssuser7dcef0
Power plants release a large amount of water vapor into the
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requirement. One of the most practical way to recover water
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plant could also recover latent heat due to condensation as well
as sensible heat due to lowering the flue gas exit temperature.
Additionally, harmful acids released from the stack can be
reduced in a condensing heat exchanger by acid condensation. reduced in a condensing heat exchanger by acid condensation.
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phenomenon since heat and mass transfer of water vapor and
various acids simultaneously occur in the presence of noncondensable
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condenser depends on the knowledge and understanding of the
heat and mass transfer processes. A computer program for
numerical simulations of water (H2O) and sulfuric acid (H2SO4)
condensation in a flue gas condensing heat exchanger was
developed using MATLAB. Governing equations based on
mass and energy balances for the system were derived to
predict variables such as flue gas exit temperature, cooling
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Student information management system project report ii.pdfKamal Acharya
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Understanding Inductive Bias in Machine LearningSUTEJAS
This presentation explores the concept of inductive bias in machine learning. It explains how algorithms come with built-in assumptions and preferences that guide the learning process. You'll learn about the different types of inductive bias and how they can impact the performance and generalizability of machine learning models.
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CW RADAR, FMCW RADAR, FMCW ALTIMETER, AND THEIR PARAMETERSveerababupersonal22
It consists of cw radar and fmcw radar ,range measurement,if amplifier and fmcw altimeterThe CW radar operates using continuous wave transmission, while the FMCW radar employs frequency-modulated continuous wave technology. Range measurement is a crucial aspect of radar systems, providing information about the distance to a target. The IF amplifier plays a key role in signal processing, amplifying intermediate frequency signals for further analysis. The FMCW altimeter utilizes frequency-modulated continuous wave technology to accurately measure altitude above a reference point.
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
Water billing management system project report.pdfKamal Acharya
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When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
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1. INTERNATIONAL UNIVERSITY
FOR SCIENCE & TECHNOLOGY
وا م ا و ا ا
CIVIL ENGINEERING AND
ENVIRONMENTAL DEPARTMENT
303322: Soil Mechanics
Introduction &Properties of Soil
Dr. Abdulmannan Orabi
Lecture
1
2. Das, B., M. (2014), “ Principles of geotechnical
Engineering ” Eighth Edition, CENGAGE
Learning, ISBN-13: 978-1-133-10867-2.
Knappett, J. A. and Craig R. F. (2012), “ Craig’s Soil
Mechanics” Eighth Edition, Spon Press, ISBN: 978-
0-415-56125-9.
References
2Dr. Abdulmannan Orabi IUST
3. Dr. Abdulmannan Orabi IUST 3
Introduction
Definition of Soil
The term soil according to engineering point of view
is defined as the material, by means of which and upon
which engineers build their structures. The term soil
includes entire thickness of the earth’s crust (from
ground surface to bed rock), which is accessible and
feasible for practical utilization as foundation support
or construction material. It is composed of loosely
bound mineral particles of various sizes and shapes
formed due to weathering of rocks.
4. Soil Mechanics is a discipline of Civil Engineering
involving the study properties of soil, behavior of soil
masses subjected to various types of forces, and its
application as an engineering material.
Introduction
4Dr. Abdulmannan Orabi IUST
Definition of Soil Mechanics
5. Soil Mechanics is the application of laws of
mechanics and hydraulics to engineering problems
dealing with sediments and other unconsolidated
accumulations of solid particles, which are produced
by the mechanical and chemical disintegration of
rocks, regardless of whether or not they contain an
admixture of organic constituents.
According to Terzaghi (1948):
Introduction
5Dr. Abdulmannan Orabi IUST
Definition of Soil Mechanics
6. Why do you need to learn about soils?
Almost all structures are either constructed of
soil, supported on soil, or both.
Introduction
6Dr. Abdulmannan Orabi IUST
7. 1. Foundation to support Structures and
Embankments
2. Construction Material
3. Slopes and Landslides
4. Earth Retaining Structures
5. Special Problems
Various reasons to study the properties of Soil:
Introduction
Why do you need to learn about soils
7Dr. Abdulmannan Orabi IUST
8. Who must be concerned with soils?
Civil engineers (structural, environmental
and geotechnical) must have basic
understanding of the soil properties in order
to use them effectively in construction.
Introduction
8Dr. Abdulmannan Orabi IUST
16. Teton Dam Failure
Dam Failure - Seepage
Problems in Geotechnical Engineering
16Dr. Abdulmannan Orabi IUST
17. Problems in Geotechnical Engineering
Dr. Abdulmannan Orabi IUST 17
Soil subjected to dynamic load
18. All soils originate, directly or indirectly, from
different rock types.
Soil Formation
Soils are formed from the physical and
chemical weathering of rocks.
18Dr. Abdulmannan Orabi IUST
Soil is generally formed by disintegration and
decomposition (weathering) of rocks through
the action of physical (or mechanical) and
chemical agents which break them into smaller
and smaller particles.
19. Soil Formation
Physical weathering
Involves reduction of size without any change in the
original composition of the parent rock. The main
agents responsible for this process are exfoliation,
erosion, freezing, and thawing.
Physical or mechanical processes taking place on the
earth's surface include the actions of water, frost,
temperature changes, wind and ice. They cause
disintegration and the products are mainly coarse soils.
19Dr. Abdulmannan Orabi IUST
21. Soil Formation
Chemical weathering causes both reduction in
size and chemical alteration of the original
parent rock. The main agents responsible for
chemical weathering are hydration, carbonation,
and oxidation.
Rain water that comes in contact with the rock
surface reacts to form hydrated oxides, carbonates
and sulphates.
The results of chemical weathering are generally fine
soils with altered mineral grains.
21Dr. Abdulmannan Orabi IUST
23. Soils as they are found in different regions can be
classified into two broad categories:
(1) Residual soils
(2) Transported soils
Soil Types
23Dr. Abdulmannan Orabi IUST
24. Dr. Abdulmannan Orabi IUST 24
Residual Soils
Residual soils are found at the same location where they have
been formed. Generally, the depth of residual soils varies
from 5 to 20 m.
Chemical weathering rate is greater in warm, humid regions
than in cold, dry regions causing a faster breakdown of
rocks. Accumulation of residual soils takes place as the rate
of rock decomposition exceeds the rate of erosion or
transportation of the weathered material. In humid regions,
the presence of surface vegetation reduces the possibility of
soil transportation.
Residual Soil
25. 25
Residual Soils
As leaching action due to percolating surface water
decreases with depth, there is a corresponding decrease
in the degree of chemical weathering from the ground
surface downwards. This results in a gradual reduction
of residual soil formation with depth, until unaltered
rock is found.
Residual soils comprise of a wide range of particle
sizes, shapes and composition.
Residual Soil
Dr. Abdulmannan Orabi IUST
26. Transported Soils
Weathered rock materials can be moved from
their original site to new locations by one or
more of the transportation agencies to form
transported soils. Transported soils are classified
based on the mode of transportation and
the final deposition environment.
Transported Soil
26Dr. Abdulmannan Orabi IUST
27. Transported Soil
Dr. Abdulmannan Orabi IUST 27
DESERT SOIL Contains soluble salts.
Originated by Mechanical disintegration & wind
deposit. Porous and coarse. 90% sand & 5% clay..
29. Transported Soils
Transported soils are classified based on the mode of
transportation and the final deposition environment.
(a) Soils that are carried and deposited by rivers are
called alluvial deposits.
(b) Soils that are deposited by flowing water or surface
runoff while entering a lake are called lacustrine deposits.
Alternate layers are formed in different seasons depending
on flow rate.
Transported Soil
29Dr. Abdulmannan Orabi IUST
30. Transported Soils
(c) If the deposits are made by rivers in sea water, they are
called marine deposits. Marine deposits contain both
particulate material brought from the shore as well as
organic remnants of marine life forms.
(d) Melting of a glacier causes the deposition of all the
materials scoured by it leading to formation of glacial
deposits.
(e) Soil particles carried by wind and subsequently deposited
are known as Aeolian deposits.
Transported Soil
30Dr. Abdulmannan Orabi IUST
31. Gravity Soils
Gravity can transport materials only for a
short distance.
Gravity soils are termed as talus these soils
are generally loose and porous.
Transported Soil
31Dr. Abdulmannan Orabi IUST
32. Soil is not a coherent solid material like steel and
concrete, but is a particulate material. Soils, as they
exist in nature, consist of solid particles (mineral
grains, rock fragments) with water and air in the
voids between the particles.
The water and air contents are readily changed by
changes in ambient conditions and location.
Phases System of Soils
32Dr. Abdulmannan Orabi IUST
33. As the relative proportions of the three phases vary
in any soil deposit, it is useful to consider a soil
model which will represent these phases distinctly
and properly quantify the amount of each phase. A
schematic diagram of the three-phase system is
shown in terms of weight and volume symbols
respectively for soil solids, water, and air.
The weight of air can be neglected.
Phases System of Soils
33Dr. Abdulmannan Orabi IUST
34. Phases System of Soils
Ground surface
Voids
Air
Water
Solids
The compositions of natural soils may include diverse components
which may be classified into three large groups:
1. Solid phase ( minerals,
cementations and organic
materials)
2. Liquid phase (water
with dissolved salts)
3. Gaseous phase (air
or other some gas)
34Dr. Abdulmannan Orabi IUST
35. Phases System of Soils
Ground surface
Voids
Air
Water
Solids
The spaces between the solids ( solid particles) are called voids.
Water is often the predominant liquid and air is the predominant gas.
We will use the terms water and air instead of liquid and gases.
35Dr. Abdulmannan Orabi IUST
36. Soils can be partially saturated (with both air and
water present), or be fully saturated (no air
content) or be perfectly dry (no water content).
In a saturated soil or a dry soil, the three-phase
system thus reduces to two phases only, as shown.
Three Phases System
36Dr. Abdulmannan Orabi IUST
37. Three Phases System
Partially saturated soil
Solid Particles
Voids (air
or water)
Idealization:
Three Phases Diagram
Water
Air
Solid Particles
37Dr. Abdulmannan Orabi IUST
38. Two - Phases System
Fully saturated soil
Solid Particles
Idealization:
Two Phases Diagram
Water
38Dr. Abdulmannan Orabi IUST
39. Two - Phases System
Dry soil
Idealization:
Two Phases Diagram
Air
Solid Particles
39Dr. Abdulmannan Orabi IUST
40. The soil model is given dimensional values for the solid, water
and air components.
Weight SymbolsVolume Symbols
Va
VS
VT
VW
VV
WT
WSWWWa≈0
Phase Relations of Soils
Water
Air
Solid Particles
40Dr. Abdulmannan Orabi IUST
41. For the purpose of engineering analysis and
design, it is necessary to express relations between
the weights and the volumes of the three phases.
The various relations can be grouped into:
Weight relations
Volume relations
Inter-relations
Three - Phases System
41Dr. Abdulmannan Orabi IUST
43. Weight Relations
Water content
The ratio of the mass of water present to the mass
of solid particles is called the water content ( ), or
sometimes the moisture content.
% =
100% (1-2)
The water content of a soil is found by weighing a sample
of the soil and then placing it in an oven at
until the weight of the sample remains constant , that is, all
the absorbed water is driven out.
110 ∓ 5 !
43Dr. Abdulmannan Orabi IUST
44. Weight Relations
Specific Gravity,
The mass of solid particles is usually expressed in
terms of their particle unit weight or specific
gravity (Gs) of the soil grain solids
The specific gravity of a solid substance is the ratio
of the weight of a given volume of material to the
weight of an equal volume of water (at 20°C).
" =
=
# $
# $
=
#
#
(1-3)
# = %& ℎ = 9.81
*+
,
44Dr. Abdulmannan Orabi IUST
45. For most inorganic soils, the value of Gs lies
between 2.60 and 2.80.
The presence of organic material reduces the
value of Gs.
Weight Relations
Specific Gravity,
45Dr. Abdulmannan Orabi IUST
The specific gravity of soil solids is often needed
for various calculations in soil mechanics.
46. The following are the basic volume relations:
Volume Relations
1. Void ratio (e)
2. Porosity (n)
3. Degree of saturation (S)
4. Air content (a)
Volume Symbols
Va
VS
VT
VW
VV
Water
Air
Solid Particles$ = $ + $ + $ (1-4)
$- = $ + $
46Dr. Abdulmannan Orabi IUST
47. Void ratio (e) is the ratio of the volume of voids
(Vv) to the volume of soil solids (Vs), and is
expressed as a decimal.
Volume Relations
Void ratio (e)
The void ratio of real coarse grained soils vary
between 0.3 and 1. Clay soils can have void ratio
greater than one.
=
$.
$
(1-5)
47Dr. Abdulmannan Orabi IUST
48. Porosity (n) is the ratio of the volume of voids to the
total volume of soil (Vt ), and is expressed as a
percentage.
Volume Relations
Porosity (n)
The range of porosity is 0 %< n < 100%
& 100% =
$.
$
100% (1-6)
48Dr. Abdulmannan Orabi IUST
49. Void ratio and porosity are inter-related to each
other as follows:
Volume Relations
Void ratio (e) & Porosity (n)
& =
$.
$/ + $.
=
$.
$/ 1 +
$.
$/
=
1 +
=
$.
$
=
$.
$ − $.
=
$.
$ 1 −
$.
$
=
&
1 − &
(1-7)
(1-8)
49Dr. Abdulmannan Orabi IUST
50. The volume of water (Vw) in a soil can vary
between zero (i.e. a dry soil) and the volume of
voids. This can be expressed as the degree of
saturation (S) in percentage.
Volume Relations
Degree of saturation (S)
Degree of saturation is the ratio of the volume
of water to the volume of voids.
1 100% =
$
$.
100% (1-9)
50Dr. Abdulmannan Orabi IUST
51. Volume Relations
Degree of saturation (S)
The degree of saturation tell us what percentage
of the volume of voids contains water .
For fully saturated soil, VV = VW, S =1 or 100%
For a dry soil, S = 0 and
For partially saturated soil 1<S<0
1 =
$
$.
$/
$/
=
1
#
#
=
"
(1-10)
51Dr. Abdulmannan Orabi IUST
52. Volume Relations
Air content (a)
The air content, a, is the ratio of air volume to
total volume .
The air- voids, Va , is that part of the voids
space not occupied by water
For a perfectly dry soil : a = n
For a saturated soil : a = 0
100% =
$
$
100% (1-11)
100% = & 1 − 1 (1-12)
52Dr. Abdulmannan Orabi IUST
53. Weight –volume relationship
Density is a measure of the quantity of mass in a
unit volume of material. Unit weight is a measure
of the weight of a unit volume of material.
Both can be used interchangeably. The units of
density are ton/m³, kg/m³ or g/cm³.
The unit of unit weight is kN/m³.
Unit weight ( )#
53Dr. Abdulmannan Orabi IUST
54. Weight –volume relationship
Unit weight ( )#
The unit weight of a soil is the ratio of the weight
of soil to the total volume.
# =
$
(1-13)
In natural soils the magnitude of the total unit
weight will depend on how much water happens to
be in the voids as will as the unit weight of the
mineral grains themselves.
54Dr. Abdulmannan Orabi IUST
55. Weight –volume relationship
Dry unit weight ( ) #2
The dry unit weight of a soil is the ratio of the
weight of solids to the total volume.
(1-14)#2 =
$
#2 =
$ 1 +
=
#
1 +
=
# "
1 +
(1-15)
# =
$
=
1 +
$
= #2 1 + (1-16)
The dry unit weight can also be determined as
55Dr. Abdulmannan Orabi IUST
59. Use
Summary
In summary, for the easy solution of phase
problem, you don’t have to memorize lots of
complicated formulas. Most of them can easily be
derived from the phase diagram. Just remember
the following simple rules:
1. Remember the basic definitions of properties
2. Draw a phase diagram
3. Assume either VS = 1 or VT = 1.
59Dr. Abdulmannan Orabi IUST
60. Dr. Abdulmannan Orabi IUST 60
Worked Examples
Example 1
An undisturbed sample of saturated clay has been
found to have a moisture content of 24 %. The
specific gravity of the solid particles was
determined as 2.7. By deriving any
relationships needed using the basic definitions
and a phase diagram for this soil, determine the
void ratio and the bulk unit weight.
61. Worked Examples
Solution of example 1
Vt =1+e
Volume
Solid
Water e
Vs =1
Weight
GS γw
e γw
(GS +e) γw
61Dr. Abdulmannan Orabi IUST
62. Worked Examples
Solution of example 1
e = 0.24 * 2.7 = 0.648
γ = (2.7 + 0.648) 9.81/(1+0.648)
γ =19.93 kN/m3
1 = 1 =
"
# =
# " +
1 +
62Dr. Abdulmannan Orabi IUST
63. Use
Worked Examples
Example 2
Prove the following relationships:
#2 = 1 − & # "
# = " − & " − 1 #
( ) =
& #
# − & #
" =
#
# − # − #
a)
b)
c)
d)
63Dr. Abdulmannan Orabi IUST
64. A soil has void ratio = 0.72, moisture content = 12%
and Gs= 2.72. Determine its
(a) Dry unit weight
(b) Moist unit weight, and the
(c) Amount of water to be added per m3 to make the
soil saturated.
Use
Worked Examples
Example 3
64Dr. Abdulmannan Orabi IUST
65. The dry unit weight of a sand with porosity
of 0.387 is 15.6
Find the void ratio of the soil and the specific
gravity of the soil solids
Worked Examples
Example 4
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65Dr. Abdulmannan Orabi IUST
66. Worked Examples
A cubic meter of soil in its natural state weighs
17.75 kN; after being dried it weighs 15.08
kN. The specific gravity of the solids is 2.70.
(a) Determine the water content, void ratio,
porosity and degree of saturation for the soil as
it existed in its natural state.
(b) What would be the bulk unit weight and
water content if the soil were fully saturated at
the same void ratio as in its natural state ?
Example 5
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67. Worked Examples
Example 6
For a given soil , the following are given : GS = 2.67;
wet unit weight ; γ = 16.8 kN/m³ moisture content
WC = 10.8 % . Determine :
1. Dry unit weight
2. Void ratio
3. Porosity
4. Degree of saturation
67Dr. Abdulmannan Orabi IUST
68. Worked Examples
Example 7
For a soil ; given γd = 16.8 kN/m3 ; e = 0.51,
determine:
1. Specific gravity
2. Saturated unit weight
3. Unit weight when the degree of saturation is 45%.
4. Saturated water content
5. Porosity.
Dr. Abdulmannan Orabi IUST 68
69. Worked Examples
Example 8
Determine the weight of water (in kN) that must be
added to a cubic meter of soil to attain a 95 % degree
of saturation, if the dry unit weight is 17.5 kN/m³,
the moisture content is 4 % and the specific gravity is
2.65.
69Dr. Abdulmannan Orabi IUST
70. Worked Examples
A project engineer receives a laboratory report with
tests performed on marine marl calcareous silt). The
engineer suspects that one of the measurements is in
error. Are the engineer’s suspicions correct? If so,
which one of these values is wrong, and what should
be its correct value? ( Gs = 2.65 )
Given: γ = 18.6 kN/m^3 , wc = 40.08 %,
e = 1.18 , and S = 90 %
Example 9
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71. Worked Examples
The bulk unit weight of the soil has been
measured as 19.17 kN/m³, the moisture content
as 25.3% and the Gs of the solid particles as
2.70. Calculate:
a) the degree of saturation, S.
b) the porosity, and
c) air content.
Example 10
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72. Worked Examples
For a saturated soil; given
γd = 15.3 kN/m^3 ; and WC = 27 %; Determine:
1. Saturation unit weight
2. Void ratio
3. Specific gravity
4. Wet unit eight when the degree of saturation
is 50 %.
Example 11
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73. A soil sample has a unit weight of 16.62 kN/m³
and a saturation of 50%. When its saturation
is increased to 75%, its unit weight raises to
17.72 kN/m³
Determine the voids ratio e and the specific
gravity Gs of this soil.
Worked Examples
Example 12
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