Ralph135.ppt 1 - Aapaq.org

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Ralph135.ppt 1 - Aapaq.org

nRalph135.pptESSENTIAL TECHNICAL REQUIREMENTSFUNDAMENTALSLONG LIFE / PERPETUAL PAVEMENTSInclude:Good materials and their characterization,good design, construction and maintenance,and …….Very Importantly Structural analysis methodologyand Performance prediction methodologyE 1,h 1E 2,h 2E 3,h 3E S,h 4Measure of Serviceabilityor Deterioration(4)P(5)(6)SubgradeMinimumAcceptable(1)(4)(2) (3)AC LayerBase Layer(1)(2)(3)(4)(5)(6)Relation / Correlation BetweenFundamental Pavement Response(s)and Pavement PerformanceP, Wheel loadRadius of loaded areaTire pressure (may not beuniform)Surface tensile stress or strainLateral shear strain ordeformationTensile strain or stress at bottomof AC layerVertical stress, strain ordeflection at surface of subgradeLife-CyclePeriodMECHANISTICPARTEMPIRICALPARTFor M-E DesignAge and/or Accumulated LoadsFACTORS AFFECTING PERFORMANCELIFE CYCLE ANALYSISENVIRONMENTTemperatureMoisture(Min., Max, ºRadiationDays, etc.)Freeze-thawCyclesSTRUCTURELayerVariationsThicknessesin ThicknessLayer Types& Properties& PropertiesSubgrade Type& PropertiesRequire: LOS vs Age (Performance) ModelCost / Cash Flow Calculation (eg. PW)Asset Value vs Age CalculationRisk AnalysisLife-CycleAxle GroupLoadsTire Types& PressuresMeasure of Serviceabilityor DeterioratioTRAFFICMinimumAcceptableAxle Spacing,Speed,RepetitionsAge and/or Accumulated LoadsPeriodTreatmentsTimingTimingMethodsMAINTENANCEMethodsCONSTRUCTIONQualityAs-BuiltQualityVarianceLevelofService(LOS)MinimumAcceptableLife-CyclePeriodAgeMETHODS OF LCCAAPPLICABILITY OF LCCA METHODS: HIGHWAYS1. Benefits / Cost Ratio2. Internal Rate of * Return3. Equivalent Uniform Annual Costs4. Cost-Effectiveness5. Present WorthWhich Method is Best for Infrastructure ?(applicability, understanding, consistency)ShortTermMediumTermLongTermArterialsPublicC/EPWCACIRRC/EPWCACIRR--PrivateIRRIRRExpresswaysPublicC/EPWCIRRC/EIRR-- IRRPrivateIRRIRRIRR2


Ralph135.pptINTERNAL RATE OF RETURN METHOD0 nLCDiscount rate at which costs and benefitsof an investment are equal(NPV x1= PWB x2,n- PWC x1,n = 0)RATE OF RETURN EXAMPLERATE OF RETURN EXAMPLE Multi-lane lane urban bypass 50 year life cycleSee Transp. Assoc. ofCanada Proc. 2005NPV ($ x 10 6 ) / lane - km for i =Financial Feasibility of an ETR ? Two long-life life (50 year) pavement designs:A. Heavy duty flexible pavementB. Plain jointed PCCP Cost estimates, traffic estimates, toll chargescheme, rehabilitation and maintenanceinterventions schedule, etc. in TAC Proc.Altern. 5% 12% 20%A(Flex.)B(PCC)15.455 1.760 -1.26115.389 1.699 -1.339NPV = 0 at IRR ~16%OBJECTIVES OFPERFORMANCE INDICATORS’Ralph HaasSusan TigheLynne Cowe FallsPERFORMANCE INDICATORS FORPROPERLY FUNCTIONINGASSET MANAGEMENTSYSTEMSExcerpts From:ARRB ConferenceCairnsMay, 2003 Assessing condition, function andsafety, (smoothness, structuraldistress, level of service, mobility, etc.) Asset value (depending on accountingbase and method) Monitoring effectiveness of policies Providing information to users Resource allocation tool Diagnostic tool… and more ...3


Ralph135.pptPolicy ObjectiveQuality of Serviceto UsersEXAMPLESPerformanceIndicator•Network smoothness(% good, fair or poor)•Annual user costs ($/km)•Provision of mobility(ave. speed by roadclass)ImplementationTarget•90% + fair orbetter•Increase CPI•> 50% speedlimitWhat is Sustainable Transportation…... A balance between transportation’seconomic and social benefits vs. the needto protect the environment …..Simply put - Do things today that don’tScrew up the FutureSafetyGoalsPreservationofInvestment•Accident reductions(%)•Asset value of roadnetwork ($)•Fatalities andinjuries by 1%annually•Increase of 0.5% annuallyShortTerm(10 to 30Years)MediumTerm(30 to 70Years)LongTerm(70 to 100Years+)USER COSTS Delays due to maintenanceand rehabilitation Vehicle operating costs Accidents Discomfort, etc.USER DELAY COST FACTORS: Delay time and value(s) of time Traffic volume Types and percent of vehicles Speed Road capacity Traffic control plan Length of work zone Geometric characteristicsSh.Sh.EXAMPLE (Pavement)1.5 mPlan 1: Stop and go (flag person)Plan 2: Divert to shoulderAADTPlan 1 UDC3 m7 m3 m4 daysPavingPlan 2 UDC5,000 $40,000 $42010,000 $550,000 $190,0004


Ralph135.pptMay 2004POSITION PAPERThe European Union Road FederationRECOMMENDATIONS: LONGLIFE/PERPETUAL PAVEMENTSFirst and foremost, the rightengineering for materials,structural design, constructionand ongoing maintenanceand Long life performance modelsRECOMMENDATIONSContinued Specifically adapted life cycleanalysis model Specifically adapted performanceindicators Specifically adapted Green Roadsrating system Comprehensive energy consumptionand emissions model5

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