geotechnical engineering centre cricos provider no 00025b the mystery of unsaturated soil mechanics...

Geotechnical Engineering CentreCRICOS Provider No 00025B

THE MYSTERY OF UNSATURATED SOIL MECHANICS – SOME MINING

APPLICATIONS

Australian Geomechanics Society, SA & NT Chapter

Monday 15 July 2013, Adeliade

Professor David J WilliamsEmail: [email protected]

Geotechnical Engineering CentreCRICOS Provider No 00025B 2

Overview

Unsaturated soil mechanics continues to play poor relation to saturated soil mechanics

An unsaturated soil at a given density performs better than same soil in a saturated state

• Some mining applications:– Wetting-up and drain down of waste rock dumps– Drain down, desiccation and rewetting of mine tailings– Drain down, desiccation and re-wetting of product coal– Bearing capacity and deformation of mine wastes– Shear strength and compressibility of clay-rich spoil– Performance of geo-covers placed on mine wastes


INTRODUCTION


Key Unsaturated Soil Mechanics Parameters

1. Shear strength:– Or capacity of a soil to support load– Simplistically, shear strength can be tested under

unsaturated conditions (adding “cohesion”)

2. Compressibility:– Or deformation of a soil under an applied load– Simplistically, compressibility can be tested under

unsaturated conditions

3. Permeability (hydraulic conductivity):– Or rate of drainage under an applied load– Assessed by SWCC and ksat testing

INC

RE

AS

ED

DE

CR

EA

SE

DD

EC

RE

AS

ED


Mining and Mineral Processing Wastes• Coarse-grained wastes (surface dumps):

– Overburden (typically up to 200 mm) or waste rock (up to 1 m), particularly from surface mining (limited from underground mining)

– Coarse reject (typically 50 mm) from coal processing– Slag or scats (typically 15 mm) from smelting– Spent heap leach material (typically 15 mm)

• Fine-grained wastes (tailings storage facilities):– Crushed and ground tailings (typically silt-size)– Erosion sediments (fines)


Waste Rock and Coarse Processing Waste Dumps

Waste rock dump

Pumped co-disposal of coal washery wastes

Coarse reject dump


Tailings Storage Facilities

Metalliferous tailings Iron ore tailings Coal tailings

Red mud Sand mining tailings In-pit coal tailings


WETTING UP AND DRAIN DOWN OF WASTE ROCK DUMPS


Impact of Waste Rock Wetting-Up

0

0.5

1

1.5

2

2.5

3

0 200 400 600 800 1000 1200 1400 1600 1800 2000

RA

INF

AL

L /

EV

AP

OT

RA

NS

PIR

AT

ION

RAINFALL (mm/year)

Kalgoorlie, WA, average annual rainfall = 250 mm

Net evapotranspirative

Net infiltrative Moistureexcess

Potential impact of waste rock dump wetting-up

Average annual rainfall ~600 mm


Wetting-Up and Drain Down of Coarse-Grained Wastes

50 min ~60 mm

25 min ~30 mm

80 min ~100 mm

Start-up


Moisture Profile after 100 mm

0.0

0.2

0.4

0.6

0.8

1.0

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4

HE

IGH

T (m

m)

LENGTH (m)

1%

1%

2%

2%

5%10

1111


Surface Infiltration into Cadia’s Trial Waste Rock Dump


Changing Infiltration into Cadia’s Trial Waste Rock Dump with Time

November 2007

May 2006

Note differential settlement-induced ponding

1313


Average Base Seepage Beneath Top and Side Slopes of Cadia’s TWRD


Trigger Rainfall and Delay for Base Seepage Following Rainfall

0

5

10

15

20

25

30

35

40

0 100 200 300 400 500 600 700 800 900 1000

CUMULATIVE RAINFALL (mm)

TR

IGG

ER

RA

INF

AL

L (

mm

)

0

5

10

15

20

25

30

35

40

DA

YS

UN

TIL

FL

OW

Flat top lysimeter rainfall trigger

Angle of repose lysimeter rainfall trigger

Flat top lysimeter delay

Angle of repose lysimeter delay

Trend linefor trigger rainfall

Trend linefor delay


Estimated Wetting-Up and Continuum Breakthrough

0

50

100

150

200

250

300

350

400

450

500

0 1 2 3 4 5 6 7 8 9 10

CO

NT

IN. B

RE

AK

TH

RU

(mm

/yea

r)

YEARS

Assumed rainfall infiltration of 450 mm(equivalent to 1.5 x 10-8 m/s)

January 2010

Possible actualbase seepage

Continuum breakthrough at:~25% saturated for fresh WR

~60% saturated for weathered WR


Estimated Time to “Continuum Breakthrough” of Waste Rock Dumps

0

200

400

600

800

1000

1200

1400

1600

1800

2000

0 20 40 60 80 100 120 140

Ave

rag

e ra

infa

ll (

mm

/yea

r)

Time to continuum breakthrough (years)

Start for 15 m height Full for 15 m heightStart for 30 m height Full for 30 m heightStart for 60 m height Full for 60 m heightStart for 120 m height Full for 120 m height

Increasingrainfall

Increasing time

Increasing dump height

17Typical mine life ~20 years, duringwhich time WRD is likely to be uncovered


DRAIN DOWN, DESICCATION AND REWETTING OF MINE TAILINGS


Impact of Tailings Slurry Deposition

0

0.5

1

1.5

2

2.5

3

0 200 400 600 800 1000 1200 1400 1600 1800 2000

RA

INF

AL

L /

EV

AP

OT

RA

NS

PIR

AT

ION

RAINFALL (mm/year)

Kalgoorlie, WA, average annual rainfall = 250 mm

Net evapotranspirative

Net infiltrative Moistureexcess

Average annual rainfall ~600 mm

Assuming 0.5 m/year rate of rise at 25% solidsor 1 m/year at 50% solids


Mt Keith Tailings Laboratory Column Test

Settled tailingsDesiccated tailings

Re-flooded tailings

20


Comparison of Field and Laboratory SWCC Data for Mt Keith Tailings

0

5

10

15

20

25

30

35

40

45

50

0.1 1 10 100 1000 10000 100000 1000000

GR

AV

. MO

IST

UR

E C

ON

TE

NT

(%

)

MATRIC SUCTION (kPa)

Average lab. re-drying SWCC Average lab. re-wetting SWCC

Field data to 0.2 m depth Field data below 0.2 m depth

Lab. column drying data

Tempe re-drying

Tempe re-wetting

Column dryingand re-drying

Laboratory Regime Field Regime

21


Comparison Between Field and Laboratory Hydraulic Conductivities

1.0E-22

1.0E-20

1.0E-18

1.0E-16

1.0E-14

1.0E-12

1.0E-10

1.0E-08

1.0E-06

0.1 1 10 100 1000 10000 100000 1000000

HY

DR

AU

LIC

CO

ND

UC

TIV

ITY

(m

/s)


Estimated field function

Average laboratory function

.

22


Sensors on Towers in Trial TSF Cell

Piezometer

TDR moisture sensor

Matric suction sensor

2323


Deposition in Trial TSF Cell

24

Desiccated tailingsFinal deposition

Early deposition Further deposition

24


Suction Data Collected from Northern TowerDeposition over 18 Months

0123456789

101112131415

0 50 100 150 200 250 300 350 400 450 500 550 600

DAYS

MA

TR

IC S

UC

TIO

N (

kPa)

1 @ 2 2 @ 2 3 @ 2 4 @ 2 5 @ 26 @ 2 7 @ 2 8 @ 2 9 @ 2 10 @ 211 @ 2 12 @ 2 13 @ 2 14 @ 2

Deposition Deposition

25

Matric Suction vs. Time

25


Suction Data Collected from Northern TowerDeposition from 17 May to 19 July & 26 Oct to 16 Nov 2007

484

484.1

484.2

484.3

484.4

484.5

484.6

484.7

484.8

484.9

485

0 10 20 30 40 50 60 70 80 90 100


SE

NS

OR

EL

EV

AT

ION

(R

L m

) 01-Jun-07 15-Jun-07 01-Jul-0715-Jul-07 01-Aug-07 15-Aug-0701-Sep-07 15-Sep-07 01-Oct-0715-Oct-07 01-Nov-07 15-Nov-0701-Dec-07 15-Dec-07 31-Dec-07

4.8 mm on 28 July 0.2 mm on 28 Sept19.6 mm on 12 Dec

26

Matric Suction vs. Depth

26


DRAIN-DOWN, DESICCATION AND RE-WETTING OF PRODUCT COAL


Dewatering and Atmospheric Effects on Product Coal

Coarse Fine Ultra-Fine

Field stockpile

11.5 m

38o


SWCCs of Product Coal Size Fractions

0

5

10

15

20

25

30

35

40

45

50

0.1 1 10 100 1000 10000

TO

TAL

MO

IST

UR

E C

ON

TE

NT

(%

)


Composite - Drying data Composite - Wetting data Composite - Drying curveCoarse - Drying data Coarse - Wetting data Coarse - Drying curveFine - Drying data Fine - Wetting data Fine - Drying curveUltra-fine - Drying data Ultra-fine - Wetting data Ultra-fine - Drying curve

2929


Duration of Applied Pressure – Centrifuging of Fine Product Coal

0

10

20

30

40

50

60

0.001 0.01 0.1 1 10 100

TO

TAL

MO

IST

UR

E C

ON

TE

NT

(%

)

TIME (hours)

~ 43%

~ 22.5%

50% dewatering

90% dewatering

3.8 min 48 min5-15 s

41 to 42%


Duration of Applied Pressure – Vacuum Filtration of Ultra-Fine Coal

0

10

20

30

40

50

60

0.001 0.01 0.1 1 10 100

TO

TAL

MO

IST

UR

E C

ON

TE

NT

(%

)

TIME (hours)

~ 42%

~ 31%

1-2 min

35 to 38%50% dewatering

90% dewatering

2.3 min 15 min

3131


Vacuum filtration vs. Briquetting of Ultra-Fine Product Coal

0

5

10

15

20

25

30

35

40

45

50

0.01 0.1 1 10 100 1000 10000 100000 1000000

TO

TAL

MO

IST

UR

E C

ON

TE

NT

(%

)


Filtered ultra-fine - Drying curve

Briquetted ultra-fine - Drying data

Briquetted ultra-fine - Wetting data

3232


Sampling Field Coal Stockpile for PSD and Moisture Content

3333


Wetting-Up of Model Coal Stockpile

3434


Stockpile Total Moisture Content Distribution

0

1

2

3

4

5

6

7

8

9

10

11

12

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

HE

IGH

T (m

)

DISTANCE FROM CENTRELINE (m)

6.3 12.3 12.9 8.5 11.1 11.9 10.0 12.1 9.5 7.4 10.5 12.6 8.2

7.7 8.2 7.7 7.7 7.8 7.8 6.3 7.5 6.0 5.5 3.7

4.7 7.7 7.7 7.5 6.9 7.6 7.2 7.8 3.5

7.0 6.5 6.8 5.3 5.6 3.2

6.7 6.2 5.7 6.1 4.6

12.1 12.1 12.3 11.2 10.5 9.2 5.0

5.5

5% total moisture content contour7.5% total moisture content contour10% total moisture content contour

3535


BEARING CAPACITY AND DEFORMATION OF MINE WASTES


Tailings Bearing Capacity Issues

1.5 m

“Bow-wave”

4-5 m

Too thin a cover over soft tailings

“Bow-waving” of crusted tailings

37


Covering Wet Tailings –Victorian Gold Mine

Surcharging edge of tailings

Spreading thin cover

D6 dozer

Ponded water due to drainageof excess pore water pressure

2-3 m surcharge

1 m cover, avoiding“bow wave” failure


Shear Strength Profiles of Coal Tailings


Safe Height of Fill on Coal Tailings

H = Nc.sv/F.~5.14.sv/(3 x 18)

~0.095 sv


SHEAR STRENGTH AND COMPRESSIBILITY OF CLAY-RICH

SPOIL


Jeebropilly Spoil – Relative Unscalped PSDs

CLAYWeathered

Rock Unweatheredcoarse-grained

Rock Unweatheredfine-grained

Rock

42


Mt Arthur Spoil – Relative Unscalped PSDs

43


Gravimetric Moisture Content vs. Matric Suction

Jeebropilly rocky spoil is less dense and wetterthan Hunter Valley spoil, although similar degree

of saturation, and hence matric suction

44


Jeebropilly Weathered Rock PSDs

45


Comparison of Direct Shear Friction Angles (-2.36 mm)

0

100

200

300

400

500

0 200 400 600 800 1000

SH

EA

R S

TR

ES

S (

kPa)

NORMAL STRESS (kPa)

Jeebropilly Weathered Rock tested dryJeebropilly Weathered Rock tested wetMt Arthur Sandstone tested dryMt Arthur Sandstone tested wet

c' = 0 kPa, ' ~ 26.6o

c' = 0 kPa, ' ~ 35.6o

c' = 0 kPa, ' ~ 41.5o

c' = 0 kPa, ' ~ 40.7o

46

Note substantial softening on wetting upof clay-rich Jeebropilly Spoil


UPC 150 mm, 10 MPa Consolidometer

47


76 & 150 mm Consolidometer Testing of Jeebropilly Weathered Rock

Note low loose density and substantial consolidationon loading and wetting of clay-rich Jeebropilly Spoil

48


76 & 150 mm Consolidometer Testing of 3-Month Old Mt Arthur Sandstone

Note high loose density and limited consolidationon loading and wetting of Mt Arthur Sandstone

49


Large Texture Changes on Weathering of Jeebropilly Weathered Rock (-19 mm)

0 days 8 days (32.6 mm rain)

21 days (+6.8 mm rain)15 days (+23.2 mm rain)

50


Large PSD Changes on Weathering of Jeebropilly Weathered Rock (-19 mm)

51


Settlement of Jeebropilly Weathered Rock with Time on Weathering (-19 mm)

52


Minimal Texture Changes on Weathering of Mt Arthur Sandstone (-19 mm)

0 days 7 days (4.0 mm rain) 14 days (+39.2 mm rain)

28 days (+6.8 mm rain)21 days (+47.8 mm rain)

53


PERFORMANCE OF STORE AND RELEASE COVERS PLACED ON

MINE WASTES


Influence of Climate – Natural Recharge (Beekmann et al., 1996)

ARIDSEMIARID Av. rainfall ~600 mmpa

~70 mm~2.2 x 10-9 m/s


Store and Release Cover on Mine Wastes

5656

Evaporationfrom ponded water

Evapotranspirationfrom vegetated surface

Rainfall

Infiltration and storage

Nominal 0.5 m compacted seal

Minor infiltration

Capillary break over tailingsor trafficked waste rock surface

Limited oxygendiffusion

and infiltration

Angle of repose waste rockor tailings

Seepagealong ~1% slope

Nominal 1 to 2 mloose, rocky soil mulch


Minor infiltration

Limited oxygendiffusion

and infiltration

Seepagealong ~1% slope


Evapotranspirationfrom vegetated surface

Rainfall

Infiltration and storage

Nominal 0.5 m compacted seal

Seepagealong slope

Nominal 1 to 2 mloose, rocky soil

Store/releasecover


Construction of Store and Release Cover on Kidston’s Waste Rock Dumps

Rocky soil mulch, capable of storingup to 300 mm rainfall/m thickness

Compacted sealing layer


Vegetation of Kidston’s Store and Release Cover12-month old trees (no

grasses) – December 200218-month old trees & 6-month

old grasses – July 2003

2-year old trees and 1-year old grasses


0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

0.5

0.55

Jun-

96

Dec-9

6

Jun-

97

Dec-9

7

Jun-

98

Dec-9

8

Jun-

99

Dec-9

9

Jun-

00

Dec-0

0

Jun-

01

Dec-0

1

Jun-

02

Dec-0

2

Jun-

03

Dec-0

3

Jun-

04

DATE

VO

LU

ME

TR

IC W

AT

ER

CO

NT

EN

T

0.35 0.75 1.37 1.75

Sensor Depths (m)

S ~ 1.0, w ~ 45%

Wet season avS ~ 0.7, w ~ 20%

Dry season minS ~ 0.2, w ~ 5%

Compacted Clayey layer

Rocky soil mulch

0200400600800

Jun-

96

Dec-9

6

Jun-

97

Dec-9

7

Jun-

98

Dec-9

8

Jun-

99

Dec-9

9

Jun-

00

Dec-0

0

Jun-

01

Dec-0

1

Jun-

02

Dec-0

2

Jun-

03

Dec-0

3

Jun-

04

RA

IN (

mm

)

59


0200400600800

Aug-9

7

Sep-9

7

Oct-97

Nov-9

7

Dec-9

7

Jan-

98

Feb-9

8

Mar

-98

Apr-9

8

May

-98

Jun-

98

Jul-9

8

Aug-9

8

RA

IN (

mm

) Total for 97/98 = 623 mm

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

0.5

0.55

Aug-9

7

Sep-9

7

Oct-97

Nov-9

7

Dec-9

7

Jan-

98

Feb-9

8

Mar

-98

Apr-9

8

May

-98

Jun-

98

Jul-9

8

Aug-9

8

DATE

VO

LU

ME

TR

IC W

AT

ER

CO

NT

EN

T

0.35 0.75 1.37 1.75

Sensor Depths (m)

S ~ 1.0, w ~ 45%

Wet season avS ~ 0.7, w ~ 20%

Dry season minS ~ 0.2, w ~ 5%

Compacted Clayey layer

Rocky soil mulch

Up to 2-week lag

k ~2 x 10-8 m/s

60


Kidston – Field SWCC Data and Fitted Curves

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.1 1 10 100 1000 10000 100000 1000000


VO

LU

ME

TR

IC W

AT

ER

CO

NT

EN

T

0.35 m depth (field data)0.35 m depth (fitted curve)1.00 m depth (field data)1.00 m depth (fitted curve)1.37 m depth (field data)1.37 m depth (fitted curve)1.77 m depth (field data)1.77 m depth (fitted curve)

Unreliable

61

Desiccatedsurface

Wetsealinglayer


Store and Release Net Percolation

0

10

20

30

40

50

60

70

80

90

100

0 2 4 6 8 10 12 14 16 18 20

NE

T P

ER

CO

LA

TIO

N(%

cu

mu

lati

ve r

ain

fall

)

AGE (years)

Cadia

Kidston

Mt Whaleback 2 m ROM-av

Mt Whaleback 2 m ROM-peak

Mt Whaleback 4 m ROM

Goldstrike


Mt Whaleback Store and Release Cover (O’Kane et al, 2012)

CRICOS Provider No 00025B

63

Note: No base sealing layer and constructed with

coarse-grained ROM waste rock, i.e. poorly-

constructed

Geotechnical Engineering CentreCRICOS Provider No 00025BCRICOS Provider No 00025B

64

Mt Whaleback Store and Release Cover (O’Kane et al, 2012)

Note: A well-constructed store and release cover

should store ~250 mm/m before percolating


Kidston – Schematic Wetting-Up and Drain Down with Time

0 5 10 15 20 25 30 35 40

INF

ILT

RA

TIO

N/S

EE

PA

GE

TIME (years)

During operation Post covering

350

300

250

200

150

100

50

0

Rainfall infiltration,diminishing exponentially

as surface compactsand with cover

Base seepage, increasing asdump wets-up, diminishing

exponentially with coverdue to drain down

Final seepage= net percolation

~7 mm/year,on average


NEW GEOTECHNICAL ENGINEERING CENTRE AT

THE UNIVERSITY OF QUEENSLAND


New Geotechnical Engineering Programs @ UQ• Commenced February 2012• Funded by Golder Associates, Rio Tinto,

AngloGold Ashanti and BHP Billiton, in partnership with UQ– Industry Partners each contributing ~$150,000/year– Matching funding from UQ– Total funding of $6 million over 5 years– 3 new academic appointments, making a total of 7:

• Professor of Rock Mechanics (to be appointed)• Lecturer in Rock Mechanics (Dr Nazife Erarslan)• Lecturer in Hydrogeology (offered)

– Plus supporting PostDocs

67


The GEC Vision• New Civil & Geotechnical Engineering and Mining

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– New Programs will have 70-75 graduates/year– Collaborative research with our industry partners

68


Civil & Geotechnical Engineering4-Year Program

2 (6%) Soil MechanicsCourses → 10

(31%) GeotechnicalEngineering Courses

(in Green)

SEM

STAT2201 Analysis of Eng & Sci Data

CIVL2130 Env Issues, Monitoring & Assessment

First Year Elective (or MATH1050, to make up

for MATHS C)

BE Civil & Geotechnical EngineeringFirst Year Elective

(Recommended: ERTH1501 Earth Processes &

Geological Materials for Engineers)

MINE3121 Mining Geomechanics

(Fundamentals of Rock Mechanics ) or ERTH1501

CIVL2360 Reinforced Concrete

Structures

CIVL4270 Geotechnical Investigation

and Testing (New)

ERTH3250 Hydrogeology (New)

1st

Sem

este

r

1ENGG1100

Introduction to Engineering Design

MATH1051 Calculus & Linear Algebra 1

First Year Elective

2nd

Sem

este

r

2ENGG1200

Introduction to Engineering Problem Solving

MATH1052 Multivariate Calculus & ODEs

ENGG1400 Statics & Dynamics

1st

Sem

este

r

3 CIVL2330 Structural Mechanics

MATH2000 Calculus & Linear Algebra II

CIVL2410 Traffic Flow Theory and

Analysis2n

dS

emes

ter

4CIVL2340

Introduction to Structural Design

CIVL2131 Fluid Mechanics

CIVL2210 Fundamentals of Soil

Mechanics

1st

Sem

este

r

5 CIVL3340 Structural Analysis

CIVL3140 Catchment Hydraulics

CIVL3210 Geotechnical Engineering (Applied Soil Mechanics )

2nd

Sem

este

r

6 CIVL3350 Structural Design

CIVL3141 Catchment Hydrology

CIVL3420 Transportation Systems

Engineering

1st

Sem

este

r

7CIVL4511 or CIVL4512

Civil Design

MINE4120 Mine Geotechnical

Engineering (Applied Rock Mechanics)

Geo Elective or Geo Project/Thesis

(CIVL4560 or CIVL4580) or MINE3121

2nd

Sem

este

r

8CIVL4520

Civil Engineering Management

ERTH2004 Structural Geology or

Geo Elective or Geo Project/Thesis

(CIVL4560 or CIVL4580)

CIVL4280 Advanced Rock Mechanics

(New)

EXISTING

NEW

NEW

NEW

NEW

NEW

NEW

NEWNEW

69


Mining & Geotechnical Engineering4-Year Program

5 (15%) MiningGeomechanics

Courses → 12 (38%)Geotechnical

Engineering Courses(in Green)

SEM

STAT2201 Analysis of Eng & Sci Data

MINE2123 Structural Mechanics in Mining

BE Mining & Geotechnical Engineering

1st

Sem

este

r

1ENGG1100

Introduction to Engineering Design

MATH1051 Calculus & Linear Algebra 1(or MATH1050, to make up

for MATHS C)

First Year Elective

ERTH1501 Earth Processes &

Geological Materials for Engineers

First Year Elective (or MATH1052 Multivariate

Calculus & ODEs)

1st

Sem

este

r

3 MINE2105 Introduction to Mining

ERTH2004 Structural Geology2n

dS

emes

ter

4CIVL2210

Fundamentals of Soil Mechanics

MINE2210 Physical & Chemical

Processing of Minerals

MINE2106Resource Geology &

Surveying

MATH2000 Calculus & Linear Algebra II

2nd

Sem

este

r

2ENGG1200

Engineering Modelling and Problem Solving

MATH1052 Multivariate Calculus

& ODEs(or MATH1051 Calculus &

Linear Algebra 1)

ENGG1400 Statics & Dynamics

6 MINE3123 Mine Planning

MINE3123 Mine Ventilation I

MINE3125 Rock Breakage

1st

Sem

este

r

5 MINE3120 Resource Estimation

MINE3121 Mining Geomechanics

(Fundamentals of Rock Mechanics )

MINE3122 Mining Systems

2nd

Sem

este

r1s

tS

emes

ter

7MINE4122

Mining Geomechanics Research Project I

MINE4124 Hard Rock Mine Design &

Feasibility

2nd

Sem

este

r

8MINE4123

Mining Geomechanics Research Project II

MINE4125 Coal Mine Design &

Feasibility

CIVL4270 Geotechnical Investigation

and Testing (New)

MINE2101 Fluid Mechanics

MINE4120 Mine Geotechnical

Engineering (Applied Rock Mechanics)

MINE4121 Mine Management

MINE4128Coal Mine Strata Control

CIVL4280 Advanced Rock Mechanics

(New)

ERTH3250 Hydrogeology (New)

EXISTING

EXISTINGEXISTING

EXISTING

EXISTING

NEW

NEW

NEW

NEW

NEW

NEW

NEW

70


Expected Geotechnical Engineering Graduations

71


Postgraduate Research Students• PhD students in Geotechnical Engineering:

– Currently 20– > 5 applications pending

• Research topics include:– Mine tailings water cycle– Effectiveness of liners for water storage ponds– Settlement of high coal mine spoil– Flow in coal seams– Behaviour of screw auger piles in clay– Problematic clay-rich coal mine tailings– Mining below the groundwater table– Erosion of granular structures– Computational geomechanics– Development and application of spatial Time Domain Reflectrometry

72

geotechnical engineering centre cricos provider no 00025b the mystery of unsaturated soil mechanics...

Documents

b waste rock

b mining

b wetting

b introduction slide

waste rock dumps slide

b impact of waste rock

startup slide

b tailings storage facilities