Issues for comments on Geometric Design.docx

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IssuesforcommentsonGeometricDesignSlNoIssuesUnderstandingandRequirementforvettingRequirementsofPPPcontractDescription/Comments,Consideration,JustificationinfavorofadoptingandreferenceinthereportComments/RecommendationbyConsultantComments/recommendationbytheProspectiveauthority1DesignTrafficAdopteddesigntrafficistobejustifiedandtobesupportedbyauthenticatedclassifiedtrafficdata.Thesourceofdata,frequencyofdata,andvalidationofdatamaybeincorporatedinthereportwhichistobeacceptedandrecommendedbythePEoftheconsultingservice/perspectiveauthority.Accordingtoclause27.2,PartA,Schedule2inPPPContract:AccordingtotherequirementsofthePPPcontract,alltrafficdatashallbebasedonthemostcurrentdata.DesigntrafficcomesfromsitetrafficvolumesurveyconductedbytheProjectCompanyinMarchtoApril2022.Atotalof4locationsweremonitoredforcross-sectionaltrafficvolume,with3ofthemalsoobservingturningtrafficvolume.Alltrafficvolumemeasurementswereconductedbyvehicletype.Videorecordingwasusedasthemethodofobservation.ComparisonamongtheMDMRMMSdatasharedbyRHDandourdata,andalsoCanadianMMMCompany’sdatain2016isasbelow.Ascanbeseenfromtheabovetable,thetrafficvolumein2019isgreaterthanthatof2016andsmallerthanthatof2022.Itobjectivelyreflectstherationalityoftheresultsofthetrafficvolumesurveyin2022.2TrafficgrowthrateInthecaseofadoptingcalculatedTrafficgrowthrate,evidence-basedjustificationistobeprovided.AdoptedtrafficgrowthrateistobeacceptedandrecommendedbythePEoftheconsultingservice/perspectiveauthority.NoconcerningrequirementshavebeenstipulatedinthePPPcontract.1.Itcanbeseenthatthepreviousforecasttrafficvolumegrowthrateinthereportishigherthanthefactualonebycomparingthetrafficvolumeof2022and2016.2.Thegrowthrateoffreightandpassengertransportinthecharacteristicyearsinthefuturecanbepredictedaccordingtotheelasticcoefficientofthefreightandpassengertransportoftheprojectandtheeconomicgrowthrate.3.ThelatestpredictionsmadebytheWorldBankandIMFcanbeareferencefortheeconomicgrowthrateoftheproject.Thepredictiondataoftrafficvolumeoftheprojectisreasonable,referto“ResearchReportonTransportNeeds”fordetails.3Opening/completionyearanddesignlifeAdoptedCompletionyear/openingyearanddesignlifeshouldbelogicallyselectedandshouldberecommendedbythePEoftheconsultingservice/perspectiveauthority.Accordingtoclause8.2,Schedule2inPPPcontractAccordingtoclause9.2,Schedule2inPPPcontractTheconstructionisexpectedtobecommencedfromtheendof2023basedonthedemolitionoftheacquiredlands.Besides,theconstructionperiodwillbe4yearsandtheas-builtyearis2026.ThedesignlifeofstructuresandpavementsisconfirmedbasedontheBangladeshcode.Indetails,100yearsforbridgestructures,50yearsforretainingwalls,20yearsformainlinepavementsand10yearsfortheserviceroads.4AlignmentselectionAdoptedalignmentselectioncriteriashouldbementioned.Anyalternationtothestandardshouldbejustified.TheadoptedalignmentselectionistobeacceptedandrecommendedbythePEoftheconsultingservice/erspectiveauthority.Accordingtoclause1.1,Schedule2inPPPcontractTheprojectstartsfromtheto-be-builtChittagonginterchangeconnectingtoN1highwayandstretchestothenorthwestalongtheR110road.ThecutoffworksarearrangedintheDermadistricttoavoidright-angledturnsandtollstationsaresetupinthemainline.Inaddition,theinterchangeissetuponMeradiainthenorthwestalongtheR202roadtoprovidetransportationconvenienceforresidentsthere.Thedestinationofourprojectwillbereachedalongtheriver Rampura,whichconnectstotheinterchangebetweenthemainroadDitroadandRampura,withatotallengthof12.448km.TheselectioncriteriaoftheroutealignmentisbasedonthePPPcontractandisfullyconsistentwiththecontract.5Lanecapacity/configuration/widthTheadoptedroadlanewidthdetailsincludinghardshoulder,shyline,dividerormedian,crossslope,footpathorwalkway,verge,embankment,servicelaneorSMVTlanedetailsetc.aretobejustified.ClarificationandrecommendationwillberequiredincaseanychangeinthelaneconfigurationisspecificallydecidedbythePEoftheconsultingservice/perspectiveauthority.Accordingtoclause7.3,Schedule2inPPPcontractTheselectionofstandardcross-sectionisbasedontheconcerningclarificationsaboutthecriteriaofgeometricdesignmadeinthePPPcontractwhiletherearesomeminoradjustments.Forexample,thelengthoftheguardrailsectionshardbythetollroadandserviceroadhasbeenchangedfrom90mto60m,whichhasbeenconfirmedafterseveralroundsnegotiationswiththeRoadsandHighwayDepartment.6Vertical/HorizontalControlAdopteddesignspeed,stoppingsightdistance,intermediatesightdistance,theminimumradiusofcurvature,maximumsuperelevation,minimumtransition,MaximumGradient,minimumKvalue,andverticalclearanceshouldbespecified.IfotherlateststandardsareselectedthenproperJustificationshouldbementionedanditshouldberecommendedbythePEoftheconsultingservice/erspectiveauthority.Accordingtoclause7.2,Schedule2inPPPcontractThedesignspeedandadoptedstoppingsightdistance,intermediatesightdistance,minimumcurvatureradius,maximumsuper-elevation,minimumtransition,maximumgradient,minimumKvalueandverticalclearanceusedinthisprojectareallderivedfromthePPPcontract,relevantBangladeshcodesandtheASSHTOCodesoftheU.S.Amongthem,theverticalclearancehasbeenspecifiedclearlyinthequestionansweringandclarificationofthebidinvitingstage:5.1mforoverpassmainroadsand4.7mforoverpassserviceroads. 7DesignmethodsTheadopteddesignmethodmustbejustifiedbyexploringandcomparingthelatestdesignmethods.ClarificationandrecommendationwillberequiredincaseofthedesignmethodisspecificallydecidedbythePEoftheconsultingservice/perspectiveauthority.Inaccordancewiththerequirementsstipulatedinthe"GeometricDesignStandardManual(Revised,2005)":Thedesignmethodadoptstherelevantrequirementsofthe"GeometricDesignStandardManual(Revised,2005)"andtheASSHTO"GeometricDesignofHighwaysandUrbanRoads(2018)"tomeettherequirementsofthePPPcontractandtheRoadsandHighwayDepartment(Bangladesh).8DesignParametersDesignparametersshouldbebasedontheadopteddesignmethodordesigncode.Everydesignparametersanditsadoptedvaluesaretobesupportedbythedesignmethod/designcodeandalsoonbasisoflocalcontext.Alltypesofdesigninput,analysis,calculation,softwareanalysis,designoutput,drawing,etc.shouldbepartofthedesignreport.Accordingtoclause7.2,Schedule2inPPPcontractInaccordancewiththerequirementsstipulatedinthePPPcontractandconcerningcodesofroadgeometricdesignofBangladeshandtheUnitedStates,allinputandoutputparameters,drawings,relatedanalysis,calculationswillbeincorporatedintothedesignreport.Theparametersadoptedare:9IntersectiondetailsTheadoptedorDesignedintersectionshouldbedesignedConsideringturningmovementdata,ODdata,presentandprojectedtraffic,anddesignvehicle(WB-20orWB-19),anditshouldberecommendedbythePEoftheconsultingservice/perspectiveauthority.NoconcerningrequirementshavebeenstipulatedinthePPPcontract.Thedesignofintersectionsinthisprojecttakesintoaccountthegradeoftheintersectedroads,trafficvolume,designvehicles,rightofwayandsoon.Besides,itcarriesoutdifferentiateddesignaswell.Mostoftheintersectedroadsatintersectionsaresecondaryroadsandtheleftturningradiusisgenerally1.5~9m.Therefore,mostvehicletypescanperformtraffictransitionsatlowspeeds.Asmallnumberofintersectionsonmajorroads,suchasintersectionswithN1NationalHighwayandDITRoad,havebeenchannelizedtoensurethatalltypesofvehiclescanpasswithinthedesignspeed. 10U-turnorU-loopTheadoptedU-turnarrangementshouldbemodifiedforWB-19/WB-20andtheU-loopshouldbedesignedconsideringproperverticalandhorizontalcontrolfactors.ClarificationandrecommendationwillberequiredincaseofthedesignmethodisspecificallydecidedbythePEoftheconsultingservice/erspectiveauthority.U-turnsaresolelydesignedforChittagongInterchangeoftheprojectandtheturningradiusofwhichis36m,meetingtherequirementsofminimalcurveradiusofWB-19/WB-20vehicles.Furthermore,theverticalclearanceoftheN1Highwayoverpassmeetstherequirementof5.1misinlinewiththecontractandthehorizontalclearancebetweenthekeyconstructionandU-turnmeetsthestandardofminimum1mrequiredinthe“GeometricStandardManual”Revised,2005).11Entry/ExitArrangementTheacceleration/deaccelerationlaneshouldbeverifiedwiththeappropriateformulaandstandards.ClarificationandrecommendationwillberequiredincaseofthedesignmethodisspecificallydecidedbythePEoftheconsultingservice/perspectiveauthority.Relatedcodesof“APolicyonGeometricDesignofHighwaysandStreets2018”areadopted.Refertorelateddeclarationsin“APolicyonGeometricDesignofHighwaysandStreets2018”forthedesigncriteriaandrequirementsoftheinterchangeentriesandexits.AnditmeetstherequirementsofthePPPcontract.12RestareaandTollplazaThedesignedrestareashouldbeunifiedwithotherongoingprojects.Thetollplazashouldbeunifiedandhavetheprovisionofelectronictollcollection.Thelocationsoftherestarea,andthespacing/distanceshouldbejustifiedbystandardandpractice.ClarificationandrecommendationwillberequiredincaseofdesignoftherestareaandtollplazaisspecificallydecidedbythePEoftheconsultingservice/perspectiveauthority.Accordingtoclause15,Schedule2inPPPcontractTheelectrictollcollectionequipmenthasbeenusedforthetollstations,refertorelateddrawingsfordetails.TheareaofthetollplazaisK4+479.5～K5+000,besides,itadoptstheprincipleof“4in4out”andtheROWof4lanesontherightisreserved.Theserviceroadsareonthetwosidesofthemainroad.Thevehiclesontheserviceroadswillnotbechargedwhileonlythenumberofvehicleswillberecorded.Thewidthofthelaneis3.5mandthewidthoftheovertakinglaneis4.5m.Besides,thelengthofthetrafficislandis37mandthewidthis2.2m.Thelengthofthetollplazais200manthewidthis58.7m.Therewillbetwoover-limitinspectionstationsinthetwodirectionsoftheplaza.Besides,themainlinetollmanagementcenters,themaintenanceareasandtrafficcontrolcenterswillbearrangedaswell.AndThedesignoftollplazasmeetstheconcerningrequirementsofthePPPcontract. 13DrainageSurfacedrainage,Sub-gradedrainage,Medianwaterdrainage,curvesection,Intersectiondrainage,andotherrelateddrainagedesignsmaybeincorporatedwithalogicalapproachandconfirmitsfunctionality.Accordingtoclause19,Schedule2inPPPcontractAccordingtoclause15,Schedule7.3inPPPcontractAcompletedrainagesystemisdesignedforthesub-gradesandtheinterioroftheproject.Thewateronthemainlinepavementscanbedrainedthroughthesurfacecrossslopesandguardraildrainageholes(orthegapditch)tothesideditchofthesub-grades.Finally,thewatercanbeledouttotheouterpartofthesub-grades.Inaddition,thecatchditchesarearrangedintheinteriorofthesuper-elevatedlanestoleadinthewaterofthesuper-elevatedpavements.Besides,sometransversedrainagepipesarearrangedtoleadthewateroutofthesub-grades.Furthermore,thetransversedrainagepipesarearrangedinsomeunfavorablepointsaswell,suchasthelowpointofcurve.14ProtectionWorkIfavailable,theriver,canal,andponddetailsurveyrequiredforprotectivework.Accordingtoclause8.2,Schedule2inPPPcontractTheprojecthasconductedadetailedsurveyoftherivers,canalsandpondsinthevicinity.Besides,protectionmethodslikeslopetoeretainingwallsforsubmergedembankmenthavebeenadopted.15Hydro-logicalcriteriaFormationlevel/free-boardshouldbesupportedbyauthenticatedBMRLandHFLRLandshouldbepresentedinaLongitudinalprofile.ThesedataaretobeacceptedandrecommendedbythePEoftheconsultingservice/Perspectiveauthority.Accordingtoclause19,Schedule2inPPPcontractThehydrologyreportoftheprojectiscompliedinaccordancewiththeapplicationcodestipulatedinthePPPcontract(calculationformulaareclarifiedorrecommendedbytheBangladeshhydrologycodeandASSHTOcode.Theparametersadoptedbytheprojectarealltakenfromthereport. 16VisibilityThevisibilityanalysisshouldbepresentedandtheminimumvalueisconfirmedlatestandavailablestandard.TherearethreeCaseEchannelintersectionsoftheprojectandtherestofwhichareCaseAtype.AccordingtothecodesinASSHTO,theedgelengthoftheCaseEintersectionsighttriangleshouldbenolessthan20m.FortheCaseEintersection,thefirstvehiclemustbeinthesightofthefirstvehicleoftherightturninglane.Thesighttriangleschematicdrawing:17RoadsignsandsignalTheadoptedroadsignsandsignalsshouldconformtotherequirementsoftheRoadSignManual(Volume1,volume2)Accordingtoclause7.4,Schedule2inPPPcontractAccordingtoclause7.8,Schedule2inPPPcontractAllthedesignsofroadsignsandsignalsoftheprojectareinaccordancewiththerequirementsstipulatedintheRoadSignManual(Vol-1&2).Notes:Thedesignfiles,surveyfiles,detailedfinaldrawings(hardandsoftcopies),detaileddesignreportandasummaryofthedesignreports(parametersandconsideredvalues)mustbeprovided.