1. EAG 345 – GEOTECHNICAL ANALYSIS By: Dr Mohd Ashraf Mohamad Ismail

2. Basic description of the course:
3 units
60 % examination; 40 % course work
40 % course work
- Test (10%)
- Assignment (20%)
- Quiz (10%)

3. Objective of the course:
To ensure the students are able to explain the soil mechanics aspect in solving problems related to:
Shear strength of soil
Site investigation
Slope stability
Passive and active earth pressure
Retaining wall
Shallow and deep foundation

4. Course outcome:
Able to explain the theories related to the geotechnical analysis
Able to analyze, calculate and solve problem in geotechnical analysis
Able to relate and discuss the theories related to the geotechnical analysis.

5. Attendance: Time table:
Less than 20% will be barred from taking final examination.
Need to pass both of the course components (i) coursework and (ii) examination
Time table:
Monday: 9.00 – am (DK5)
Wednesday: 9.00 – am (DK8)

6. Rules and regulations in class:
Come to class on time.
Attend to personal needs before coming to class.
Do not eat in class unless you have been given special permission (can drink! No problem).
Bring required materials every day unless you are otherwise directed.
Talk only when permitted or necessary.
Use polite words and body language when asking questions.
Do not cheat during quiz, assignment, test and examination.

7. Reference:
Budhu, M. (2010). Soil Mechanics and Foundations (3 ed.): Wiley.
Das, B. M. (2010). Fundamentals of Geotechnical Engineering (3 ed.): CL-Engineering.
Das, B. M. (2009). Principles of Geotechnical Engineering (7 ed.): CL-Engineering.
Craig, R. F. (2004). Craig's Soil Mechanics (7 ed.): Spon Press.
Mitchell, J. K., and Soga, K. (2005). Fundamentals of Soil Behavior (3 ed.): Wiley.
Terzaghi, K., Peck, R. B., and Mesri, G. (1996). Soil Mechanics in Engineering Practice (3 ed.): Wiley-Interscience.
Duncan, J. M., and Wright, S. G. (2005). Soil Strength and Slope Stability (1 ed.): Wiley.
Das, B. M. (2010). Principles of Foundation Engineering (7 ed.): CL-Engineering.
Waltham, T. (2002). Foundations of Engineering Geology (2 ed.): Spon Press.
Dunnicliff, J. (2008). Geotechnical Instrumentation for Monitoring Field Performance (1 ed.): Wiley-Interscience.
Holtz, R. D., and Kovacs, W. D. (2010). An Introduction to Geotechnical Engineering (2 ed.): Prentice Hall.

8. Teaching plan : Dr Mohd Ashraf Mohamad Ismail (P) – 6 weeks
Prof. Dr. Nor Azazi Zakaria – 2 weeks
Prof. Dr. Fauziah Ahmad – 6 weeks

9. Quiz 1:
In a piece of paper give the definitions for the terminology as listed below:
Unit weight
Liquid limit
Degree of saturation
Void ratio
Hydraulic conductivity
Name 2 types of soil classification system
Example of cohesive and cohesionless type of soils

10. Answer for Quiz 1:
Unit weight – the weight density (weight divided by volume)
Liquid limit – the water content at which a soil changes consistency from a plastic state to a liquid state
Liquidity index – A index quantifying the current state (water content) of a soil relative to the liquid and plastic limits
Optimum water content (OMC) – The water content attained by a soil at a maximum dry unit weight in a proctor compaction test
Hydraulic conductivity – the rate of flow of fluid through soils

11. Assignment 1:
In a group of 5 or 6 ( 1 Malaysia) list down all the terms together with the definition (brief and straightforward) that you think important in the listed chapter below:
Origin of soil and grain size
Weight volume relationship
Plasticity and structure of soil
Classification of soil
Soil compaction
Permeability and seepage
In-situ stresses
Compressibility of soil (consolidation and etc.)
Due date: 24 September 2012; before 5.00 pm

12. Mechanical and hydraulic properties
Assignment 2:
Design a flow chart that best represent the flow/process involved in the geotechnical engineering (from desk study until the evaluation after construction) and highlighted the whereabouts of the shear strength soil component in the whole process ?
Index properties
Mechanical and hydraulic properties
Site investigation
Laboratory test
Numerical modeling
Laboratory test
Design and analysis
In-situ field test
evaluation
Due date: 3 December 2012 before 5.00 pm
Format of submission: Microsoft Visio Format and hard copy in A3 size

13. Flow of the study

14. Laboratory experiment: (EAA 305)
Proctor Test
Sieve analysis and Atterberg limit test
Permeability and field density test
EAA 305 briefing:
Date: will be decided later
Time: 13 September 2012
Venue: BK1 PPKA
Attendance: Compulsory (will be deduct 5 marks from first laboratory test for those who are not coming without any acceptable reason)

15. Outdoor Class Piezocone (CPT) Electrical Resistivity survey
The date will be decided later !!
Piezocone (CPT)
Electrical Resistivity survey
Seismic refraction survey
Borehole and SPT
Mackintosh probe

16. s = (πs2/a)* [1- (a2 / 4s2)] R; s ≥ 5a
ARRAY SELECTION – SCHLUMBERGER
Schlumberger Array:
s = (πs2/a)* [1- (a2 / 4s2)] R; s ≥ 5a
Reasonable all round alternative array if both good horizontal and vertical resolution is needed (to detect horizontal and vertical structure) C2 P2 P1 C1 3a a
n = 3 3 C2 P2 P1 C1 a 2a
n = 2 2 a C1 P1 C2 P2
Schlumberger Array
n = 1 1
Determine the electrodes spacing
Identifying survey line (RES 1)

17. Development of tension crack line Enhance water infiltrationB1 B8 B3 B4 B2 L1 M1 M2 B6 B7 B5 L2 M3
LS1
LS2
LS3
LS4
LS5
LS6
Effect of Cavitation
Two Fractured Zone
Natural
Slope Side
Cut
Scale: 1: 556
LS = Loosened / Dry Sandy to Silty Materials
(High Resistivity Zone)
B = Granitic Boulders (High Resistivity Zone)
L = Low Resistivity Zone (Clays or Clay Rich Soil and Highly Saturation Zone)
M = Moderate Resistivity Zone (Silty to Sandy Materials in Permeable and Less Permeable Condition)
Zone of High Saturation
Sampling Point
Desiccation cracks
Toward the
slope face
Development of tension crack line
Enhance water infiltration
M1, M2 and M3 = More Permeable Zone
RES 1 – Schlumberger Array model (1 m electrode spacing)
Qualitative correlation between the resistivity values in the models with the borehole data and also hand auger information
Broad range of electrical resistivity values – indicator to the heterogeneity of the subsurface materials encountered – variable engineering properties characteristics
Geophysical signatures obtained by the other researches in similar and comparable geological environment – used for correlation purpose

18. Shallow Seismic Refraction Survey
TELUK BAHANG DAM
FEDERAL ROUTE 6
SRF 1
SRF 2
SRF 3
BOREHOLE
Shallow Seismic Refraction Survey
SRF 1
SRF 2
SRF 3

19. SHEAR STRENGTH OF SOILS

20. Objectives: You will learn:
How to determine the shear strength of soils
Understands the differences between drained and undrained shear strength
Determine the type of shear test that best simulates field conditions
How to interpret laboratory and field test results to obtain shear strength parameters.
Important of Shear Strength for geotechnical engineering application

21. (i) Shear failure of soils

22. Would you like this to happen?
The failure occurs because the shear strength of the soil is exceeded.
We need to determine the soil’s shear strength and design the slope so that the shear stress imposed is not greater than the shear strength of the soil.

23. Strength of different materials
Soil
Shear strength
Presence of pore water
Complex
behavior
Steel
Tensile strength
Concrete
Compressive strength

24. Strength of different construction materials
Example of material involved in the construction of suspension bridge:
Steel = suspension cable
Concrete = road deck
Soil/Rock = foundation
Load
Load
Steel
Concrete
Soil/Rock
Load

25. Unfortunately soil is not man made such as concrete or steel.
Strength of soil
Virtually all the Civil Engineering projects come into contact with soil either on soil, in soil or made off soil.
For example:
Foundation
Slope
Tunnel
Slope
Foundation
Tunnel
Unfortunately soil is not man made such as concrete or steel.
Its undergone natural processes which make it a complex and heterogeneous materials which feature a wide range of mechanical/hydraulic behaviors

26. Shear failure of soils Soils generally fail in shear
Strip footing
Embankment
Failure surface
Mobilized shear resistance
At failure, shear stress along the failure surface (mobilized shear resistance) reaches the shear strength.

27. Shear failure of soils - Embankment
Embankment Failure

28. Shear failure of soils
Soils generally fail in shear
Retaining wall

29. Shear failure of soils Soils generally fail in shear
Failure surface
Mobilized shear resistance
Retaining wall
At failure, shear stress along the failure surface (mobilized shear resistance) reaches the shear strength.

30. Shear failure of soils – Retaining wall

31. Shear failure mechanism
failure surface
The soil grains slide over each other along the failure surface.
No crushing of individual grains.

32. Shear failure mechanism 
At failure, shear stress along the failure surface () reaches the shear strength (f).