Lecture 3-

Road Transport I

Section 1 Vehicle Types

Section 2 Technical Aspects

ROAD TRANSPORT ILECTURE STRUCTURE

VEHICLE TYPESMOVEMENT OF GOODS BY ROAD

Many types of vehiclesSuited to all types of cargoCarry small volumes / weights

Compared to rail or inland waterwaysDoor-to-door service

Cargo transported from origin to destination Driver accompanied

Highly competitive

VEHICLE TYPESKEY CHARACTERISTICS

Dominates inland freight movements> 90% inland goods value $$$$> 80% inland freight volume> 6,000 billion tonne-kilometres per year in the EU,USA, CIS, China and Japan

Majority over short distance85% carried <150 km<1% is carried over 1,000 km

Road freight volumes continue to increase

VEHICLE TYPESIMPORTANCE OF ROAD TRANSPORT

Motor vehicleMechanically propelled (has an engine)Used on roadsCarries freight and / or passengers

Goods vehicleOnly carries freight

SynonymsTruckLorryHaulage vehicle

VEHICLE TYPESDEFINITIONS

Propulsion unitEngineCab

Type depends onWeight of cargo to be carriedDistance to be travelled

VEHICLE TYPESROAD TRACTOR UNITS

Cargo carrying unitHighly flexible

Easily coupled and uncoupled from tractor unitsEasily moved by shunters

Two typesDraw-bar trailer

Supports weight of cargo on its wheels when uncoupledSemi-trailer

Legs support the weight when not coupled to the tractor unit

VEHICLE TYPESROAD TRAILERS

Draw-bar Trailer Semi-trailer

Rigid vehicleSingle unit

Tractor and trailer units combinedCannot be uncoupled

Articulated vehicleTractor and trailer are separate unitsTractor and trailer may be coupled and uncoupled

VEHICLE TYPESRIGID & ARTICULATED VEHICLES

Rigid Vehicle

Tractor Trailer

Articulated Vehicle

VEHICLE TYPESGOODS VEHICLE TYPES

Van Flat Bed Box Body

Specialist

Road TrainHeavy LiftWide Load

Curtain Sided

Tanker

Tipper

Low Loader

Rigid formCharacteristics

Highly flexibleCarry 1-3 tonnesOften based on car design

ApplicationsCourier businessMail distributionHome deliveries

VEHICLE TYPESSMALL VANS

Rigid or articulated formDesigned with a platform on which goods are carried

May have drop sides to secure loads Flexible and can accommodate oversized loadsCargo must be secured

RopesTwist locks

Cargo may require covering for protectionSheeting

VEHICLE TYPESFLAT BED

Rigid or articulated formCargo carrying area is enclosed

Protects cargo from weatherProvides good cargo security

Access from rear of vehicle

VEHICLE TYPESBOX BODY

Carry temperature-sensitive loadsChilled or frozen products

Made of insulated material with a refrigerator unit attached May be designed with one or more temperature compartments (zones)

PowerMain engineSeparate engine (genset)

TECHNICAL ASPECTSBOX BODY – TEMPERATURE CONTROLLED

Fibreglass-reinforced plastic (FRP)Advantages

Strong and cheaperDisadvantage

Relatively heavy

AluminiumAdvantages

Light &Easy to repair

DisadvantagesExpensiveNot robust for heavy loads

VEHICLE TYPESBOX BODY - CONSTRUCTION

Articulated or rigidFixed roofed frame with a flexible curtain (tarpaulin)

Curtain fixed to both sides of the frameSecured with straps

Provides easy access for efficient loading and unloading

VEHICLE TYPESCURTAIN SIDED

Less secure than box (rigid) bodied vehiclesSusceptible to damage

TearingIn high winds tarpaulin left open to reduce wind impact

VEHICLE TYPESCURTAIN SIDED

Rigid vehiclesTypically smaller vehiclesEasy to drive in confined / congested areas

Articulated vehicle (tractor + trailer)More manoeuvrableTend to be larger Greater load capacity / length

Better ratio between tare and cargo weightsTractor can leave trailer to be (un)loaded

VEHICLE TYPESARTICULATED VS RIGID VEHICLE

Tare Weight – the weight of the vehicle or container when

empty

Gross Weight – the weight of the vehicle or container and

the cargo

Net Weight = Gross Weight –Tare Weight

VEHICLE TYPESRIGID VS CURTAIN SIDED VS WINGBODY

Most commonly operate in AsiaIt is called wing body truck because it looks like a bird spreading the wings when the sides of the cargo bay are openedLoading and unloading are possible from both sides

Excellent access to all goodsLong and thin goods can also be put in and out easily.

WingsManual or hydraulicCanvas of rigid

VEHICLE TYPESWING BODY TRUCKS

Tank fitted to the chassisCargos carried

Liquids (petrol, water)Gases (oxygen)Powders (cement)Foodstuffs (milk, grain)

Cross contamination concernsIndustrialFoods stuffs

VEHICLE TYPESTANKERS

Rigid Tanker Tanker Trailers

Rigid or articulated formsOpen top body

Loaded by gravity (payloader / hopper / grab)Unloaded when body is tipped backwards (using a hydraulic arm) and tailgate released

Typical loads include aggregatesSoil, sand and stoneMajor contributor to road damage

Weighbridges used to check weight of vehicles

VEHICLE TYPESTIPPERS

Transport large (over sized) loadsUse of low loaders or other specialise equipment150T or more

Major impact on other road usersMay be restricted by route / time of dayMay require police / outriders / escort vehicle

Includes non road vehiclesMining trucks with payloads >300T

VEHICLE TYPESSPECIALIST

Tractor unit pulls two or more trailersTypical cargo / goods carried

FuelDry bulksGeneral freightLivestock

Australia - largest road trains in the world80 to 120 tonnesAlso found in Argentina, Mexico, USA and Canada

Used in remote areasLow populationLow road traffic volumes

Singificant impact on other road users

VEHICLE TYPESSPECIALIST - ROAD TRAINS

Section 1 Vehicle Types

Section 2 Technical Aspects

ROAD TRANSPORT ILECTURE STRUCTURE

TECHNICAL ASPECTSANATOMY OF A TRACTOR-TRAILER

Typical semi-trailer truck

1. Tractor unit (chassis) 2. Semi-trailer (detachable) 3. Engine 4. Drivers cab5. Sleeper (not present in all trucks) 6. Air dam – aero dynamics7. Fuel tanks 8. Fifth wheel coupling9. Cargo space 10. Legs11. Axles

11

Structural skeleton of the vehicleDetermines size and shape of the truck

Design is a major influence on fuel economyIncludes

CabAxlesEngineFuel tankBattery

TECHNICAL ASPECTSCHASSIS

Off-road vehicleLimited powerShunt (move) trailers in

Container terminalsRo-Ro terminalsManufacturing sitesDistribution centres

TECHNICAL ASPECTSTERMINAL SHUNTER UNITS

Key characteristicsEngine power (horsepower)

Maintain speed over long distanceSpeed of accelerationMore needed for long distance or high speed work

Pulling power (torque)Force to move vehicle from stationary startPower to pull up hill (gradient)More needed for heavier loads and greater gradient

Engine choice depends onJourney – long distance or local deliveryWeight of cargo (load)Road speeds

TECHNICAL ASPECTSENGINE

Number of fuels availableDiesel (most common)BiofuelsLPG / CNGElectricHybrid-electric

Major cost element30% operational costsRising fuel prices impact profits

Increasing focus on fuel efficiency viaDriving techniquesGood maintenance Tractor and trailer design (aero dynamics)Tyre & wheel designTare weight reduction

TECHNICAL ASPECTSFUEL

TECHNICAL ASPECTSFUEL

Derived: www.truckbuyersguide.gov.au

Fuel Details Advantages Disadvantages

Diesel • Standard • Widely available • Increasing cost• High emissions

Biofuels • Ethanol – from sugar cane or other plant materials

• Biodiesel –from vegetable oil or animal fat

• Lower emissions• Used by standard trucks

• Blended with other fuels• May void vehicle

warranties

LPG / CNG • Limited application for haulage – city (urban) deliveries

• Cheaper than diesel• Low pollution levels

• Typically retro-fitted• Cost of installation

Electric • Rechargeable battery• Limited haulage use

• Zero emissions • Expensive

Hybrid-electric • Conventional fuel with on-board rechargeable battery

• Best on local pick up and delivery

• Benefits from both technologies

• Better fuel economy (10-14%)

• Expensive• Negligible benefit for open

road driving

Combines conventional engine technology with electric propulsion system

Achieves better fuel economy and performancePort of Long Beach, USA

Testing hybrid tractor units to move containers Engine will not idle when not moving

Diesel units consume power when not movingTractors stand still 50 – 80% of time when in use

BenefitsMay be recharged from the electric gridEmissionsImproved energy efficiencySavings of 3,000 gallons / shunter / annum

TECHNICAL ASPECTSHYBRID VEHICLES

Distributes gross weight of the vehicle onto road surfaceProvides stability and motion of vehicle and even breakingNumerous axle / trailer combinations availableSubject to strict national regulations

TECHNICAL ASPECTSAXLES

Choice depends onTractor unit engineMileageCargo weightRoad conditions

ImpactsFuel efficiencyRoad noise

Maintenance importantUnder inflation

Fuel cost +6.25% if 10% under inflatedReduced tyre life by 10% to 40%

Blowouts (loss of control / serious accidents)

TECHNICAL ASPECTSTYRES

Towing mechanism between tractor unit and semi-trailerComprises

Horseshoe-shaped device (fifth wheel) on tractor unitCoupling pin (kingpin) on front of the semi-trailer

Once in position the semi-trailer landing gear is raisedAirlines and electrical leads link tractor to trailer

Provide power for lights / temperature controlBreaking capability

TECHNICAL ASPECTSFIFTH WHEEL (TRACTOR-TRAILER)

Fifth Wheel

Coupling Pin

Truck driving and operationPerformance monitoringTruck status / diagnostics

CommunicationsNavigation and routeingIT and office administrationVisibility of vehicle to office

Living accommodationSleeping quartersEntertainment systemsEating (microwaves…)

TECHNICAL ASPECTSDRIVERS CAB

TECHNICAL ASPECTSANATOMY OF A TRAILER

Depends on cargoShape WeightVolume

Access to cargo is important with respect toSecurityLoading / unloading at origin / destination

Facilities at origin / destination may impact body choice

TECHNICAL ASPECTSBODY

Number of design options availableTear drop trailers

Design reduces drag resistanceLafarge (UK)

Reduction in fuel costs by 10% Reduce carbon emissions by 120 tonnes per year Use of LNG will provide further cost / emission savings

TECHNICAL ASPECTSINCREASING EFFICIENCY BY DESIGN