Technologies for Evaluating Risks to Existing Berth

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Technologies for Evaluating Risks to Existing Berth Infrastructure from Larger Vessels

2019 Facilities Engineering Seminar

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Risks Posed by

Larger Vessels

1. Navigation

2. Passing other docks

3. Maneuvering at berth

4. Berthing

5. Mooring

6. (other)

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Navigation

CMA CGM Ben Franklin

Port of Oakland, CA

Comprehensive vessel accommodation study,

included maneuvering, surge effects, berthing and mooring.

Particular CMA CGM Ben Franklin

Length Overall (ft) 1309

Breadth (ft) 177

Moulded Depth (ft) 99

Draft (ft) 52.5

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Navigation


Port of Oakland, CA

Maneuvering simulations define suitable environmental

conditions, pilot procedures, and data for surge analysis.

Simulations at CA Maritime Academy

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Navigation


Port of Oakland, CA

High resolution PPU equipment provide better

maneuvering guidance and accuracy than available on

many vessels.

Pilots required the PPUs with 2nd pilot for VLCVs over 1200’

LOA.

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Navigation


Port of Oakland, CA

Navigation practice re-enacted after simulations.

Surge effects were single

greatest concern for pilots.

Simulations provide accurate data for simulation of surge

effects.

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Passing Other Docks

(Surge Effects)

Surge effects are nothing new…

https://www.belfasttelegraph.co.uk/news/northern-ireland/titanic-near-miss-that-could-have-changed-course-of-history-30636858.html

http://www.maritimequest.com/liners/titanic_page_6.htm

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Passing Other Docks

(Surge Effects)

Surge effects are nothing new…

…but good understanding of

surge effects is recent.

Many facilities do not have adequate consideration of

surge effects.

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Passing Other Docks

(Surge Effects)


Port of Oakland, CA

Surge modeling performed using maneuvering patterns

taken from full bridge.

Loads imposed by passing ships can rival wind loads

during storm events.

Surge modeling results used to evaluate mooring risk,

develop navigation guidance.

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Passing Other Docks

(Surge Effects)


Port of Oakland, CA

Mooring simulations help define risk to berth

infrastructure from bypassing.

Evaluates motions, downtime, fenders, bollards, mooring

lines.

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Passing Other Docks

(Surge Effects)


Port of Oakland, CA

Bypassing guidance can be developed for better

understanding of risks.

Safe Mooring

Use Caution

Potentially Unsafe

Pilot Bypassing Guidance

0.0

1.0

2.0

3.0

4.0

5.0

6.0

0 100 200 300 400 500

Pa

ssin

g S

pe

ed

[kts

]

Clear Distance Between Hulls at Midships [ft]

+

CT3

Passing Other Docks

(Surge Effects)

Cruise Terminal 3

Port Canaveral

Surge effects simulated Port-wide for mooring design, and

bunkering safety analysis.

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Passing Other Docks:

Bunkering

Cruise Terminal 3

Port Canaveral

LNG bunker barges are relatively small → passing ship

surge forces should be manageable.

Surge-related challenges are

mostly spatial conflicts, and development of suitable

mooring arrangements.

https://www.portcanaveral.com/getattachment/About/LNG-at-Port-Canaveral/LNG-Bunkering-Info.pdf.aspx?lang=en-US

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Maneuvering at Berth

Propulsion systems on

new/larger vessels can affect berth stability

CFD simulations are now

routine and efficient.

FLOW3DAzipods at 50% applied power, directed 45 deg aft Azipods at 50% applied power, directed starboard

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Propulsion Effects and

Scour Protection

CFD analysis demonstrates shortcomings in existing

systems, or new efficient designs.

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Fender Suitability for

Larger Vessels

Port of Oakland

Berth Infrastructure Risk Assessment

Fender capacity guidelines (e.g. PIANC) are intended for new

installations.

Some recommendations should not necessarily be applied to evaluate

risks to existing systems.

Data show lower impact velocities for larger vessels.

Burkhart et al (PIANC Work ing Group 145)

0

5

10

15

20

0 50000 100000 150000 200000 250000 300000

Bert

hin

g V

elo

city [cm

/s]

DWT

10k TEU

14k TEU

19k TEU

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Larger Vessels

Port of Oakland


Probability of different berthing velocities can be quantified.

Combined with consequences, can

inform risks of utilizing existing fenders.

Berthing Velocity (cm/s)

~2.5 yr

~10 yr

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Larger Vessels

Port of Oakland


Real-world experience shows that this makes sense.

Pilot procedures for VLCVs

• 2 pilots• 4 tugs

• Daylight• Wind/current/tide/draft restrictions

• PPU equipment

Low berthing velocities + low berthing angles = High Loads in Existing Fenders are NOT Likely

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1193’ ship at berth during 30-knot winds

Bollard Suitability for

Larger Vessels

Port of Oakland


AIS data show that vessels don’t necessarily leave the dock during

wind events.

High bollard loads are possible, and probability should be evaluated with

site-specific wind data.

Ships > 1100’ LOA at berth

0

50

100

150

200

250

300

0 10 20 30 40 50

Bo

llard

Lo

ad (k

ips)

Wind Speed (kts)

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Bollard Suitability for

Larger Vessels

Port of Oakland


Risks to bollards are berth-specific.

Not all berths need the same bollards to achieve safe mooring.

Some berths with lower bollard

capacities may still have lower risk.

1yr wind10yr windSE Winds

SE Winds

Fender and Bollard Suitability for

Larger Vessels - Conclusions

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+0.75

▪ Risk is not only about probability, but also

consequence.

▪ Risk can be quantified.

1. Define probabilities using suitable analysis.

2. Define consequences using damage evaluation.

3. Combination of these informs risk.

▪ Accommodating larger vessels may carry

acceptable level of risk for existing

fenders/bollards.

Consequence

5 (Very High)

4

3

2

1 (Very Low)

1 (Very Low) 2 3 4 5 (Very High) Probability

Risk (Consequence x Probability)

Consequence

Probability

RISK

High

Medium

Low

Bollard Load

Fender Load

Edge Beam

Summary

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+0.75

▪ New, larger vessels bring new potential risks.

▪ Analysis tools can help understand/minimize risks.

▪ A prepared analysis toolkit can be deployed very

quickly upon notice of imminent larger vessels.

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Technologies for Evaluating Risks to Existing Berth Infrastructure from Larger Vessels

Scott W. Fenical, PE, D.CE, D.PE

Coastal Practice Leader

T +1 (415) 773 2164 C +1 (415) 341 4669

[email protected]

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2019 Facilities Engineering Seminar

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Technologies for Evaluating Risks to Existing Berth