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Navigational depth

Best practice in Rotterdam approachesJeroen van Reenen

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Navigational depth

1 Port environment

2 Dredging mangement

3 Navigational depth

4 Density surveying

5 Investigation surveys

6 Research siltation in Rotterdam ports

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River estuary

Tidal water

River discharge

Salt water currents

Storms

1 Port Environment

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5

6

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2 Dredging management

By area

By organisation

By contract

By dredging equipment

By navigational depth definition / measurements

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Port of Rotterdam / Rijkswaterstaat

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Dredging contract type

TDS based

Time based

Combination TDS/Time

Lum sum contract

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Dredging equipment

Size of hopper dredgers

Submersible pump

Use of plough vessel

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3 Navigational depth

Fluid mud

Measurement systems

Data processing / charting

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Navigational depth parameters

Viscosity [N*s / m2]

Sheer stress [N / m2]

Density [kg / m3]

PIANC (1983)

1) The ship’s hull must suffer no damage even if its draught reaches the full navigable depth

2) The navigation response of the vessel must not be adversely affected

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Minimum UKC

Berge Stahl

343 m long

63 m wide

365.000 T

354.000 T @ 23m

3 deg roll, 1.65m

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Rotterdam definitions

Navigational depth at 1200 g/l density level

Multibeam echosounding for “top of siltation layer”

Assuming top of siltation 1030 g/l

Density measurment to detect layer 1030-1200 g/l

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4 Density surveying

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21

22

23

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950 1050 1150 1250 1350 1450

Slibdichtheid [kg/m3]

Die

pte

[m]

1200

kg/

m3

1030

kg/

m3

Echosounder depth

1.2 T/m3 depth

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Density measurments

Weight

Radio active counting

Tuning fork

Acoustics

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DensiTune

Tuning fork technique

Fluid mud layer detection up to

1250 gr/l

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Density-depth chart

1030 g/l: 23.25 m

1200 g/l: 23.47 m

Density layer: 0.22 m

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DensiTune point export

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DensiTune Calibration

Get a representative local fluid mud sample

If density is not over 1200 g/l give time to settle

Drain water

No more stirring than necessary to get a homogeneous sample

Min. 5 different density measurements by adding sea water to sample material

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Van Veen grab

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Calibration barrel

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DensiTune calibration

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Check on measurements against calibration

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Point measurements

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TIN model

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Isopach DTM

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SILAS raw data

Digital 200 KHz

SILAS 1.2 density

Echo “noise”

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Calibration of Silas

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Singlebeam tracks

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Monitor tracks

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Long sections

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Authority boundary

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Multibeam depth (240 KHz)

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Navigational depth (1200 g/l)

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Navitracker

Nucleair system

Used verticale

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23,0

23,1

23,2

23,3

23,4

23,5

23,6

23,7

23,8

23,9

24,0

24,1

24,2

24,3

24,4

24,5

24,6

24,7

24,8

24,9

25,0

950 1000 1050 1100 1150 1200 1250 1300 1350 1400

Density

Dep

th DensiTune

NaviTracker

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Slib tank Antwerpen tests

Check accuracy of DensiTune system

Check on accuracy of Silas system

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DensiTune results

Slibtank ma 13-09-2010

-300

-250

-200

-150

-100

-50

0

1000 1050 1100 1150 1200 1250 1300

Density [gr/l]

Z [

cm]

DensiTune 4.8m

Staal 5.5m

DensiTune 5.8m

DensiTune 6.8m

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Silas results

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New development undisturbed bottom sampling

Based on standard Beeker-sampler

Free fall triggering

Altitude and attitude monitoring

Density measurement by Anton Paar calibrated instrument

Convert sample profile data for Silas echosounder calibration

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Free fall Beeker sampler

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Sample density measurement

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5 Siltprofiler surveys

Water column profiling

Current measurements

Water samples for calibration

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Siltprofiler

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OBS dataPoint 2 evolution OBS2

-3000

-2500

-2000

-1500

-1000

-500

0

500

-20 0 20 40 60 80 100 120 140

concentration (mg/L)

Dep

th (

cm)

6h40

7h36

10h35

11h44

12h59

13h51

14h55

15h55

16h45

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6 Research siltationForces of nature

Current

River discharge

Tide

Salinity

Wind force and direction

Temperature

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Current and tide

Transport of suspended sediment

River flow against tidal currents

Eddies in port basins

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Current profiles

Tide at Scheurhaven

-100

-50

0

50

100

1500

:00

2:0

0

4:0

0

6:0

0

8:0

0

10

:00

12

:00

14

:00

16

:00

18

:00

20

:00

22

:00

0:0

0

Time (MET)

Tid

e [

cm

NA

P]

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Suspendedsediment

Point 1 evolution OBS2

-3000

-2500

-2000

-1500

-1000

-500

0

500

0 20 40 60 80 100 120 140

concentration (mg/L)

Dep

th (

cm)

6h31

8h13

9h24

10h26

11h33

12h46

13h39

14h42

15h39

16h34

17h31

Tide at Scheurhaven

-100

-50

0

50

100

150

0:0

0

2:0

0

4:0

0

6:0

0

8:0

0

10

:00

12

:00

14

:00

16

:00

18

:00

20

:00

22

:00

0:0

0

Time (MET)

Tid

e [

cm

NA

P]

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Salinity

Flud from Sea

River flow

Wedge mixing

Surface mixing

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Salinity / siltation

Salinity/ Thickness 2009

0

5

10

15

20

25

30

35

0 50 100 150

days

(C)

0

0,1

0,2

0,3

0,4

0,5

0,6

cm

Salinity 9m

Salinity 4,5m

Salinity 2,5m

Thickness

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Wind

Wind creates waves, waves bring sediment into the water column

Wind influences the tide

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Windforce 2009

wind force/Dredging 2009

0

1

2

3

4

5

6

0 5 10 15 20 25 30

weeks

Bea

ufo

rt

0

20000

40000

60000

80000

100000

120000

140000

160000

m³

wind speed

dredging

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Temperature

Water temperature range 5 – 20 deg

Microbiology in bottom layers

Methane gas production

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Temperature / dredging

Temperature/Dredging 2008

0

5

10

15

20

25

0 100 200 300

Days

(C)

0

20000

40000

60000

80000

100000

120000

140000

160000

180000

200000

Temperature 9m

Temperature 4,5m

Temperature 2,5m

Dredging amount

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Temperature / Siltation layer

Temperature/Thickness 2008

0

5

10

15

20

25

0 100 200 300

Days

(C)

0

0,1

0,2

0,3

0,4

0,5

0,6

0,7

0,8

0,9

Temperature 9m

Temperature 4,5m

Temperature 2,5m

Thickness

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Thank you for your attention