大三下学习老交通工程课件

Roadwaysandtheirgeometric道路基本特路网密道路结道路线道路网布公路网布局形放射形路三角形路并列形路树叉形路城市路网布棋盘带放射放射环兰州路东京的路新加坡的路Mobilityand机动性和可达Mobilityreferstothethroughmovementofpeople,goods,andvehiclesfromPointAtoPointBAccessibilityreferstothedirectconnectiontoabuttinglandsandlandusesprovidedbyroadwaysConceptsofmobilityand机动性和可道路分类分 ongeometricdesignofhighwaysandstreets,2001（Greenbook）城市道路设计规范，CJJ37-HierarchyofroadwayHighwayway(LimitedaccessProviding100%throughNodirectaccesstoabuttinglandusesisSurfacefacilitiesforthroughButpermitsomeaccesstoabuttingIntermediatecategory way,arterialslocalSomemeasureofbothmobilityandaccessLocalAccesstoabuttinglandTypicalruralandurbanroadway

ways,otherways,expresswaysMajororprincipalarterials,MinorMajorcollectors,MinorLocal

Residential,Commercial,ExampleinsuburbanresidentialAnopengrid高速公六车道45000～80000一级公六车道二级公路，供汽车行驶的双车道公路；三级公路，供汽车行驶的双车道公路；四级公路，供汽车行驶的双车道或单车道公路；2000以下，400以公路行政等级总里程：410.64

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其国省国省县乡公城市道路城市道路交通规划设计支小区 HighwaydesignHorizontalalignment（平面线形Verticalalignment（纵断面线形Cross-sectionalelements（横断面公路设RogerL公路选线、 设路基路桥涵洞交通安全设施、标志挡土声屏HorizontalRefersto nviewofIncludestangentsectionsandthehorizontalcurvesandothertransitionHighwaydesignisgeneratedinitiatedbylayoutasetoftangentsontopographicalanddevelopmentmapsoftheserviceareaConsiderationinselectingForecastdemandvolumes,withknown-orprojectedorigin-destinationpatternsPatternsofNaturalSubsurfaceDrainageEconomicEnvironmentalSocialSurveyingandRoutesurveyorsdefinethegeometryofahighwaybystakingoutthehorizontalandverticalpositionoftheCriticalcharacteristicsofcircularhorizontalcurvesP.I.pointofP.C.pointofP.T.pointofTlengthofEexternalMmiddleordinateL.C.Long∆externalangleofRradiusofSuperelevationofhorizontal12%is umsuperelevationinWhensnowandiceareprevalent,aumvalueof8%isusedInurbanareas,speedsmaybereduced umvalue4%-6%Lowspeedurbanstreetsoratintersections,superelevationcouldbeDesignvalueofside-frictionWetpavementsandtiresinreasonablebutnottop DeterminingdesignvaluesofR＝minimumradiusofcurvature,metersS=speed,km/hf=coefficientofsidefrictione=superelevation,expressedasdecimalAchievingTangentSpiraltransitionAspiraltransitioncurvebeginswithatangentandgraduallyanduniformlyincreasethedegreeofcurvatureuntiltheintendedcirculardegreeofcurveisVirtualimpactofspiraltransition∆SightdistanceonhorizontalMinimumsightdistanceequalstothesafe distancemustbeprovidedateverypointalongtheroadwaySightdistanceismeasuredalongthearcoftheroadway,usingthecenterlineoftheinsidetravellaneMAminimumPageVerticalThedesignoffacilityintheprofileIncludesgradesandverticalSuretoAdequatesightdistanceatallAdequateMaintenanceofcomfortableMaintenanceofreasonableVerticalAreintheshapeofProvidesanaturaltransitionfromatangenttoacurvedsectionaspartofthecurvecharacteristicsGrade,thelongitudinalslopeofaumum CrawlingCrestverticalcurvesandsagvertical凸形竖曲线、凹形竖SightdistanceonverticalForcrestcurves,thedaylightsightcontrolstheminimumlengthofverticalForsagcurves,theheadlamprangeduringnighttimedrivingcontrolsMeasuredfromanassumedeyeheight3.5ft(1.1m)andanobjectheightof2.0SightdistanceforcrestSightdistanceforsagDesignguidelinesforverticalAsmoothgradelinewithgradualchangesispreferredtoalinewithnumerousbreaksandshortProfilesshouldavoidtheroller-coasterappearance,aswellashiddendipsinthealignmentUndulatinggradelinesinvolvingsubstantiallengthofmomentum(down)gradesshouldbecarefullyevaluatedwithrespecttooperationoftrucksBroken-backgradelines(two-consecutiveverticalcurvesinthesamedirectionseparatedbyashortsection)shouldbeavoidedwhereverpossible八达岭高 方向潭峪沟隧翟忠民 DesignguidelinesforverticalcurvesOnlonggrades,itmaybepreferableto cethesteepestgradesatthebottom,lighteningthegradeontheascent.Ifthisisdifficult,shortsectionsoflightergradesshouldbeinsertedperiodicallytoaidWhereat-gradeintersectionsoccuronroadwaysectionswithmoderatetosteepgrades,thegradeshouldbereducedorflattenedthroughtheintersectionareaSagverticalcurvesincutsshouldbeavoidedunlessadequatedrainageisprovidedCross