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.

1. 1
Geotechnical Engineering–I [CE-221]
BSc Civil Engineering – 4th Semester
by
Dr. Muhammad Irfan
Assistant Professor
Civil Engg. Dept. – UET Lahore
Email: mirfan1@msn.com
Lecture Handouts: https://groups.google.com/forum/#!forum/geotech-i
Lecture # 4
1-Feb-2017

2. 2
S: Solid Soil particle
W: Liquid Water
A: Air Air
REVIEW:
Soil as a Three Phase System

3. 3
REVIEW:
PHASE RELATIONSHIPS
w
b
d


1


n
n
e


1
e
e
n


1
VG
W
n
ws
s 1
.
1 

1
..

s
ws
W
GV
e










e
w
G wsb
1
1
.
e
G ws
d


1
.

S
Gw
e s.

 
e
eG ws
sat



1


 
 e
Gsw
sub



1
1

rv Sn.

4. 4
PHASE RELATIONSHIPS
Problem #1
The wet density of a glacial outwash soil is 1.92 g/cm3 the
specific gravity of the solid particles of the soil is Gs = 2.67,
and the moisture content of the soil is w = 12% by dry
weight.
CALCULATE:
a) Dry density
b) Porosity
c) Void ratio
d) Degree of saturation
e) Percentage of air voids

5. 5
PHASE RELATIONSHIPS
Problem #2
From a borrow pit in which the void ratio is 1.20, 200,000 m3
of soil have to be excavated for building a fill with a void ratio
of 0.70. How many cubic meter of fill can be constructed?
Problem #3
The moisture content of a saturated clay sample is 345%. The
unit weight of the solids is 2.38 g/cm3. Determine the unit
weight of the saturated clay (g/cm3).

6. 6
PHASE RELATIONSHIPS
Problem #4
The unit weight of the solids of a given sand is 2.60 g/cm3. Its
void ratio is 0.573.
CALCULATE:
a) The unit weight of the dry sand
b) The unit weight of the sand when saturated
c) The submerged unit weight of the sand
Problem #5
One cubic cm of wet soil weight 2.0g. Its dry weight is 1.8g.
The specific gravity of the particles of soil is 2.67. Determine
the moisture content, porosity, void ratio, degree of saturation
and volumetric water content.

7. 7
PHASE RELATIONSHIPS
Problem #6
A clay sample, at its natural moisture weighs 34.62g. The
specific gravity of the soil particles of soil is Gs = 2.7. After
oven drying, the soil sample weighs 20.36g. To determine the
volume of moist clay, the sample is immersed in mercury prior
to oven drying. The displaced volume of clay sample is found
to be 24.26 cm3
.
CALCULATE:
a) Moisture content
b) Void ratio,
c) Degree of saturation
d) Volumetric water content

8. 8
CONCLUDED
REFERENCE MATERIAL
An Introduction to Geotechnical Engineering (2nd Edition)
By R. D. Holtz, W. D. Kovacs and T. C. Sheahan
Chapter #2
Geotechnical Engineering – Principles and Practices - (2nd Edition)
By Donald P. Coduto, M. R. Yeung and W. A. Kitch
Chapter #4
Fundamentals of Soil Mechanics
By M. S. Qureshi & Aziz Akbar
Chapter #3