PC

The Owner’s Perspective

on

Crane Wheel Load

Considerations

The Owner’s PerspectiveThe Owner’s Perspective

onon

Crane Wheel Load Crane Wheel Load

ConsiderationsConsiderations

PC

Wheel Load ConsiderationsWheel Load ConsiderationsWheel Load Considerations

New Wharf Design Preparation

Larger Cranes on Existing Wharves

New Wharf Design PreparationNew Wharf Design Preparation

Larger Cranes on Existing WharvesLarger Cranes on Existing Wharves

PC

Evolution of Wheel LoadsEvolution of Wheel LoadsEvolution of Wheel Loads

In Virginia andOther Ports

In Virginia andIn Virginia andOther PortsOther Ports

PC

1959 1959 PacecoPaceco

340 tons340 tons

PC

1967 1967 PacecoPaceco482 tons482 tons

PC

1969 1969 PacecoPaceco

730 tons730 tons

PC

1972 1972 PacecoPaceco 868 tons868 tons

PC

1985 1985 KoneKone Dual Hoist 1094 tonsDual Hoist 1094 tons

PC

1990 1990 CemcoCemco 954 tons954 tons

PC

1997 1997 NoellNoell 1157 tons1157 tons

PC

2003 ZPMC 1656 tons2003 ZPMC 1656 tons

PC

2004 ZPMC Elevating Girder Crane 1826 tons2004 ZPMC Elevating Girder Crane 1826 tons

PC

2005 ZPMC Twin Forty 1858 tons2005 ZPMC Twin Forty 1858 tons

PC

Preparations for Designinga New Wharf –

Operational Considerations

Preparations for DesigningPreparations for Designinga New Wharf a New Wharf ––

Operational ConsiderationsOperational Considerations

Crane Type

Crane parameters

Brief Case Study

Crane TypeCrane Type

Crane parametersCrane parameters

Brief Case StudyBrief Case Study

PC

Single HoistSingle Hoist

Dual HoistDual Hoist

oror

PC

Standard A FrameStandard A Frame

Low profileLow profile

oror

PC

Twin TwentyTwin Twenty

Twin FortyTwin Forty

oror

PC

Rope Tow TrolleyRope Tow Rope Tow TrolleyTrolley

Machinery on Machinery on TrolleyTrolley

oror

PC

Specialty CranesSpecialty Cranes

PC

Other Operational ConsiderationsCrane parameters

Other Operational ConsiderationsOther Operational ConsiderationsCrane parametersCrane parameters

Outreach

Lift height

Backreach

Rated capacity

Local storm wind

OutreachOutreach

Lift heightLift height

BackreachBackreach

Rated capacityRated capacity

Local storm windLocal storm wind

PC

Case StudyVirginia Wharf Expansion

Case StudyCase StudyVirginia Wharf ExpansionVirginia Wharf Expansion

PC

PC

Crane TypeCrane TypeCrane TypeSingle Hoist or Dual Hoist ?

Rope Tow Trolley (RTT) or Machinery on Trolley (MOT) ?

Single Hoist or Dual Hoist ?Single Hoist or Dual Hoist ?

Rope Tow Trolley (RTT) or Machinery on Rope Tow Trolley (RTT) or Machinery on Trolley (MOT) ?Trolley (MOT) ?

PC

Advantages of MOTAdvantages of MOTAdvantages of MOT

Reduced maintenance expense • less wire rope

• Fewer sheaves

• No wire supports

Potential for increased reliability.

Reduced maintenance expense Reduced maintenance expense •• less wire ropeless wire rope

•• Fewer sheavesFewer sheaves

•• No wire supportsNo wire supports

Potential for increased reliability.Potential for increased reliability.

PC

Disadvantages of MOTDisadvantages of MOTDisadvantages of MOTIncreased wheel loads – 15 – 30%Potential wheel slipHeavier festoonIncreased energy consumptionSlower trolley accelerations

Increased wheel loads Increased wheel loads –– 15 15 –– 30%30%Potential wheel slipPotential wheel slipHeavier festoonHeavier festoonIncreased energy consumptionIncreased energy consumptionSlower trolley accelerationsSlower trolley accelerations

PC

VIT Operator Tests VIT Operator Tests APL CranesAPL Cranes

PC

Crane ParametersCrane ParametersCrane Parameters

Outreach 26 wide

Lift height 130 feet Backreach 75 feet

Rated capacity 65/80 tons

Storm wind 110 mph ASCE Basic

Outreach 26 wide Outreach 26 wide

Lift height 130 feet Lift height 130 feet BackreachBackreach 75 feet75 feet

Rated capacity 65/80 tons Rated capacity 65/80 tons

Storm wind 110 mph ASCE BasicStorm wind 110 mph ASCE Basic

PC

Resulting Wharf DesignResulting Wharf DesignResulting Wharf DesignBasis:• Rope tow trolley cranes• 1 out of 8 cranes to be a specialty crane

Elevating Trolley Girder • Increase in crane parameters

Wheel load requirement +40%over existing 100 ft gage wharf

Basis:Basis:•• Rope tow trolley cranesRope tow trolley cranes•• 1 out of 8 cranes to be a specialty crane1 out of 8 cranes to be a specialty crane

Elevating Trolley Girder Elevating Trolley Girder •• Increase in crane parametersIncrease in crane parameters

Wheel load requirement +40%Wheel load requirement +40%over existing 100 ft gage wharfover existing 100 ft gage wharf

PC

Controlling Wheel Loadsfor Larger Cranes on Existing

Wharves

Controlling Wheel LoadsControlling Wheel Loadsfor Larger Cranes on Existing for Larger Cranes on Existing

WharvesWharves

PC

Reduce Structural MaterialReduce Structural MaterialReduce Structural Material

Boom

Leg and beam members

BoomBoom

Leg and beam membersLeg and beam members

PC

Lattice BoomLattice Boom

vicevice

Box Beam BoomBox Beam Boom

PC

Redistribute WeightRedistribute WeightRedistribute Weight

Change trolley stow location

Change boom stow position

Change trolley stow locationChange trolley stow location

Change boom stow positionChange boom stow position

PCChanging Boom Stow PositionChanging Boom Stow Position

PC

Other Ways to ReduceWheel Loads

Other Ways to ReduceOther Ways to ReduceWheel LoadsWheel Loads

Reduce wind loads• Aerodynamic shaped members• Narrower members

Limit Outreach

Reduce wind loadsReduce wind loads•• Aerodynamic shaped membersAerodynamic shaped members•• Narrower membersNarrower members

Limit OutreachLimit Outreach

PCLimited OutreachLimited OutreachNew Cranes on Existing WharfNew Cranes on Existing Wharf

PC

Justify Higher Wharf LoadsJustify Higher Wharf LoadsJustify Higher Wharf LoadsRevaluate wharf design• Strut and tie method

Review pile driving records

Load test wharf

Strengthen the wharf - expensive

Revaluate wharf designRevaluate wharf design•• Strut and tie methodStrut and tie method

Review pile driving recordsReview pile driving records

Load test wharfLoad test wharf

Strengthen the wharf Strengthen the wharf -- expensiveexpensive

PC

Bottom LineBottom LineBottom Line

New wharf …………..Plan Ahead

Existing wharves……….Be creative

New wharf …………..New wharf …………..Plan AheadPlan Ahead

Existing wharves……….Existing wharves……….Be creativeBe creative