1. Introduction to Geotechnical Engineering
ground
N. Sivakugan
Duration: 11 min 56 s

2. Typical Geotechnical Project
Geo-Laboratory ~ for testing
Design Office ~ for design & analysis
soil properties
design details
soil samples
construction site

3. Geotechnical Applications

4. Shallow Foundations
~ for transferring building loads to underlying ground
~ mostly for firm soils or light loads
bed rock
firm ground

5. Shallow Foundations

6. Deep Foundations
~ for transferring building loads to underlying ground
~ mostly for weak soils or heavy loads P I L E
bed rock
weak soil

7. Deep Foundations
Driven timber piles, Pacific Highway

8. Retaining Walls ~ for retaining soils from spreading laterally
Road
Train
retaining wall

9. Earth Dams
~ for impounding water
soil
reservoir
clay core
shell

10. Concrete Dams
reservoir
soil
concrete dam

11. Concrete Dams
Three Gorges Dam, Hong Kong

12. Concrete Dams

13. Earthworks ~ preparing the ground prior to construction
Roadwork, Pacific Highway

14. Construction hazard ~ an unwelcome visitor at an earthwork site.
What does it have to do with Geo?#!
A dead Anaconda python (courtesy: J. Brunskill)

15. Geofabrics
~ used for reinforcement, separation, filtration and drainage in roads, retaining walls, embankments…
Geofabrics used on Pacific Highway

16. Reinforced Earth Walls
~ using geofabrics to strengthen the soil

17. Soil Nailing
~ steel rods placed into holes drilled into the walls and grouted

18. Sheet Piles
~ sheets of interlockingsteel or timber driven into the ground, forming a continuous sheet
ship
warehouse
sheet pile

19. Sheet Piles ~ resist lateral earth pressures
~ used in excavations, waterfront structures, ..

20. Sheet Piles
~ used in temporary works

21. Sheet Piles
~ interlocking sections

22. Cofferdam
~ sheet pile walls enclosing an area, to prevent water seeping in
Cofferdams are often used in temporary works, to enclose the construction area within a continuous sheet pile wall around and protect it from water entering from outside.

23. Landslides

24. Shoring
propping and supporting the exposed walls to resist lateral earth pressures

25. Tunneling

26. Blasting
For ore recovery in mines

27. Ground Improvement
Impact Roller to Compact the Ground

28. Ground Improvement
Sheepsfoot Roller to Compact Clay Soils

29. Ground Improvement
Smooth-wheeled Roller

30. Ground Improvement
Big weights dropped from 25 m, compacting the ground.
Craters formed in compaction

31. Environmental Geomechanics
Waste Disposal in Landfills

32. Instrumentation
~ to monitor the performances of earth and earth supported structures
~ to measure loads, pressures, deformations, strains,…
Finally, proof of the pudding is in the eating. Very often we monitor the performances of foundations, tie backs, embankments etc. for a long time after construction, to verify that it is performing to our expectations. Geotechnical engineering involves lots of uncertainty in the soil properties used in the designs and the theories. Instrumentation is a popular method to verify the theories, assumptions, construction methods etc.

33. Soil Testing
Cone Penetration Test Truck – Lavarach Barracks, Townsville

34. Soil Testing Vane Shear Test Standard Penetration Test
More Field Tests

35. Soil Testing
Triaxial Test on Soil Sample in Laboratory

36. Soil Testing
Variety of Field Testing Devices

37. Soil Testing Purdue University, USA
Being Pushed around by my Supervisors

38. Typical Safety Factors
Type of Design
Safety Factor
Probability of Failure
Earthworks
1/500
Retaining structures
1/1500
Foundations
1/5000

39. Some unsung heroes of Civil Engineering…
foundations
soil exploration
tunneling
All structures need proper foundations. To design good foundations, it is essential to know the geotechnical characteristics of the underlying ground. The only way to know them is to test the soil.
… buried right under your feet.

40. Great Contributors to the Developments in Geotechnical Engineering
Hall of Fame
Great Contributors to the Developments in Geotechnical Engineering

41. Siva’s teacher in USA – deserves gold frame
WJM Rankine
A.Casagrande
C.A.Coulomb
Karl Terzaghi
Siva’s teacher in USA – deserves gold frame
L. Bjerrum
A.W.Skempton 1914-
G.F.Sowers
G.A. Leonards

42. Geotechnical Engineering Landmarks
Challenges
Geotechnical Engineering Landmarks

43. Leaning Tower of Pisa
Our blunders become monuments!

44. Hoover Dam, USA
Tallest (221 m) concrete dam

45. Petronas Tower, Malaysia
Tallest building in the world

46. Monuments
and….

47. CS2005: Geo-Engineering I

48. Geo-engineering at JCU
CS2005 Geo-engineering I
CS3002 Geo-engineering I
CS4001 Geo-engineering I
Postgrad MEngSc/PhD

49. Practicals ~ five practical sessions
~ closed footwear must be worn in the lab

50. Laboratory Staff
Neville Hines & Rudd Rankine

51. Quizzes How? about 4-6, 50 minutes each open book Why?
to reinforce main points
provides a wake up call
form of assessment

52. Past CS2005 Grades
1996
1997
1998
1999
2000
2001
2002 HD 5 1 3 ? D 4 2 9 6 C 15 12 7 P 8 10 P- N 14 13 X
Total 54 33 35 39 42

53. Some Suggestions Attend the lectures.
It takes longer to understand from the lecture notes
Develop a good feel for the subject.
It is practical, interesting and makes lot of sense.

54. Some Suggestions
Work in groups.

55. Some Suggestions
Thou shall not wait till the last minute.

56. Exams
My mama always said, “Exam is like a box of chocolates; you never know what you are gonna get”