A-POLICY-ON-GEOMETRIC-DESIGN-OF-HIGHWAYS-AND-STREE

ADDENDATOTHE1997MASSHIGHWAYHIGHWAYDESIGNMANUALINTERIMGUIDANCEFORCONFORMANCEWITHTHEAASHTOAPOLICYONGEOMETRICDESIGNOFHIGHWAYSANDSTREETS2001APRIL2003INTERIMGUIDANCETOTHE1997HIGHWAYDESIGNMANUALThefollowinginformationisaddendatothe1997MassHighwayHighwayDesignManual.ThesechangesweremadetoaddressupdateddesignguidancefromtheAASHTOAPolicyonGeometricDesignofHighwaysandStreet2001(GreenBook).SignificantchangesweremadefromthepreviousversionoftheAASHTOGreenBookthataffectthedesignofroadwaysinMassachusetts.ThesechangesweremadebyAASHTOdesigncommitteestoaddresstheneedforimprovedsafetyandmobilitywhilerecognizingtheneedforagenciesanddesignerstobemoresensitiveintheirapproachtodesign.OnMarch14,2002,theFederalHighwayAdministration(FHWA)officiallyadoptedthe2001AASHTOGreenBookasminimumdesignstandardsforprojectsontheNationalHighwaySystem.Atthattime,theFHWAgavethestatesoneyeartoaddresscomplianceoftheGreenGookwiththeirownstandards.Thisdocumentservesthatpurpose.Changesweremadeprimarilytoaddressitemsaffectingthe13AASHTOcontrollingcriteria.Inaddition,thisdocumentincludesdimensionsinboththeEnglishandMetricsystemsofmeasurement,withmostdimensionsroundedtoevenEnglishvalues.Designersshoulddesigntodesirablestandardswherepracticalandminimumstandardswherefeasible.ThisistheflexibilityindesigninherentintheAASHTOguidance.Thecontextoftheroadwayshouldalwaysbeconsideredandexceptionstotheminimumstandardsmaybewarrantedbasedonconstraints.Thenormallyrequiresjustificationanddocumentationintheformofadesignexceptionreporttoassurethatthedesignerusedsoundengineeringjudgmenttoaddresssafetyandmobilityobjectives.MassHighwayiscurrentlyconsideringmoresignificantrevisionstotheHighwayDesignManualrelativetocontextsensitivityandcommunityconcerns.Intheinterimperiodbetweennowandwhenafullyrevisedmanualisissued,thisdocumentshouldbeusedtodesignallroadwaysinMassachusetts.Sincemostofthevaluescontainedinthisdocumentarewithintherangeofthedesirableandminimumstandardsinthe1997HighwayDesignManual,projectscurrentlyunderdesignorconstructionmaycontinuetousethe1997valuesatthedirectionoftheprojectmanager.ADDENDUMTOTHE1997HIGHWAYDESIGNMANUALPage3.12.0Section3.4.1DesignSpeedFirstsentenceisreplacedwiththefollowing:Designspeedisaselectedspeedusedtodeterminethevariousdesignfeaturesoftheroadway.Page3.13.0Section3.4.1DesignSpeedTable3.6isreplacedwiththefollowingTable:Table3.6DESIGNSPEEDS(ADesignExceptionisrequiredwhenspeedselectedisoutsideTableValues)MetricUnits(meters)FUNCTIONALCLASSIFICATIONU/RDESIGNSPEEDURBANDESIGNSPEEDSHOULDNOTBELESSTHAN80km/hFREEWAY/EXPRESSWAYRURAL110km/hSHOULDBEUSED,INMOUNTAINOUSTERRAIN,ADESIGNSPEEDOF80km/hTO100km/hMAYBEUSEDURBANMAYRANGEFROM50km/hTO100km/h.BELOW70km/hAPPROPRIATEFORBUILT-UPAREAS.ABOVE80km/hISAPPROPRIATEFOROUTLYINGAREAS.ARTERIALRURALLEVEL-100to120km/hROLLING-80to100km/hMOUNTAINOUS-60to80km/hURBANMINIMUMOF50km/hCOLLECTORRURALOVER2000ADT:LEVEL-100km/hROLLING-80km/hMOUNTAINOUS-60km/hSEEPAGE426OF2001AASHTOPOLICYONGEOMETRICDESIGNFORADTBELOW2000.LOCALURBANMAYRANGEFROM30km/hTO50km/hDEPENDINGONAREACONTROLS.RURALOVER2000ADT:LEVEL-80km/hROLLING-60km/hMOUNTAINOUS-50km/hSEEPAGE385OF2001AASHTOPOLICYONGEOMETRICDESIGNFORADTBELOW2000.Table3.6(CONTINUED)DESIGNSPEEDS(ADesignExceptionisrequiredwhenspeedselectedisoutsideTableValues)EnglishUnits(feet)FUNCTIONALCLASSIFICATIONU/RDESIGNSPEEDURBANDESIGNSPEEDSHOULDNOTBELESSTHAN50mphFREEWAY/EXPRESSWAYRURAL70mphSHOULDBEUSED,INMOUNTAINOUSTERRAIN,ADESIGNSPEEDOF50mphTO60mphMAYBEUSEDURBANMAYRANGEFROM30mphTO60mph.BELOW45mphAPPROPRIATEFORBUILT-UPAREAS.ABOVE50mphISAPPROPRIATEFOROUTLYINGAREAS.ARTERIALRURALLEVEL-60to75mphROLLING-50to60mphMOUNTAINOUS-40to50mphURBANMINIMUMOF30mphCOLLECTORRURALOVER2000ADT:LEVEL-60mphROLLING-50mphMOUNTAINOUS-40mphSEEPAGE426OF2001AASHTOPOLICYONGEOMETRICDESIGNFORADTBELOW2000.LOCALURBANMAYRANGEFROM20mphTO30mphDEPENDINGONAREACONTROLS.RURALOVER2000ADT:LEVEL-50mphROLLING-40mphMOUNTAINOUS-30mphSEEPAGE385OF2001AASHTOPOLICYONGEOMETRICDESIGNFORADTBELOW2000.Page3.14.0Section3.4.2RunningSpeedThirdparagraph:replace30km/hto70km/hwith30km/hto75km/h.Page3.15.0Section3.4.3PostedSpeedDeleteFigure3-2Page3.17.0Section3.5.1.3CompositionFirstparagraph:replace4100kilogramswith4000kilogramsPage3.18.0Section3.5.1.4LevelsofServiceSecondparagraph:replaceTable3.7withTheHighwayCapacityManual(HCM)Page3.18.0Section3.5.1.4LevelsofServiceTable3.8isreplacedwiththefollowingTable:Table3.8MINIMUMLEVELOFSERVICEGUIDELINESTYPEOFAREAANDAPPROPRIATELEVELOFSERVICEHIGHWAYTYPERURALLEVELRURALROLLINGRURALMOUNTAINOUSURBANANDSUBURBANFREEWAY1BBBCARTERIALBBCCCOLLECTORCCDDLOCALDDDDNote:LEVELOFSERVICED,E,ANDFARENOTNORMALLYUSEDFORDESIGN.1.SEEHIGHWAYCAPACITYMANUALTODETERMINELEVELOFSERVICEFORFREEWAYSINDESIGNYEAR.Reference:“APOLICYONGEOMETRICDESIGNOFHIGHWAYSANDSTREETS”AASHTO,2001”Page6.43.0Section6.6.1.2CrossSectionsLastline,replacewiththefollowingsentence:RefertoTable5.1forrecommendedroadwaysectionwidths(travellanewidthsandshoulderwidths)forfigures6-18,6-19,6-21through6-29.Page7.01.0Section7.1.2VehicleConsiderationReplacethelastparagraphwiththefollowing:Vehiclesturning