TrafficSignalControlSystems

北美交通信號控制系統

TheNorthAmericaPracticeAboutRenoandUNROutline主要內容Majortrafficflowandsignalcontrolcharacteristics-USAvs.China(中美交通流特性及信號控制）Signalcoordinationanddemo(信號協調實例演示）3TrafficFlowCharacteristics

中美交通流特性對比4Lowusageofpublictransportation公共交通低利用率Highusagepublictransport公共交通高利用率高USAChinaAutomobileisdominant小汽車為主Mixedflowwithhigh%pedestriansandbicycles混合車流，行人自行車高比例Easyaccesstofreeway

高速免費，穿過市區Tolledfreewayoutsidecityboundary高速收費，城市外圍shortpeakperiod短高峰peakthroughouttheday長高峰????IntersectionCharacteristics

交叉口特性IntheU.S.,thereareabout300,000signals(1per1,000population).InChina,thereareabout50,000in2010withapproximately5,000peryeargrowth.MostsignalizedintersectionsinChinaarehighlycongestedwithheavypedestrianandbicyclevolumes.Fixedtime(China)vs.actuated(US)UnsignalizedintersectionsaremostlyuncontrolledinChina.PedestrianIssues(行人問題)Safetyvs.Efficiency(安全與效率)Pedestriancrossingissparseatsignals(信號交叉口行人稀少）Mustaccommodatepedestriantiming

(行人過街時間必須保證)Pedestrianshavehigherpriority(行人優先)PedestrianSignalPolicyandUniformity

政策與規范Therearevariousmanualsthatdefinethestandardandguidelinesfortrafficsignalcontrol,suchastheMUTCDandtheSignalTimingManual（美國有各種規范標準）Engineers(notthepolice)manageandoperatetrafficsignals（工程師與交警）PermittedLTDisplayinChinaFYATianjinChiaTianJinSignalBeijingChiaShanghaiChiaExtendedLeft-turnWaitingArea

左轉待行區ExtendedwaitingLTarea–willitincreasecapacity?SignalTimingTerminologies

信號配時術語Basicsignalterms基本信號組成Cycleandcyclelength周期和周期長度Interval時段Changeinterval(yellow)Clearanceinterval(all-red)GreenintervalRedintervalPhase=Green+Yellow+All-red

(*Asignalphaseisassociatedwithaparticulartrafficmovement)TrafficMovements

One-wayStreets單行線流向MainStreetSideStreetNEBNBMainStreetSideStreetNEBNBTrafficMovements

One-wayStreetsMainStreetSideStreetNEBNBTrafficMovements

One-wayStreetsMainStreetSideStreetNEBNBTrafficMovements

One-wayStreetsMainStreetSideStreetNEBNBTrafficMovements

One-wayStreetsMainStreetSideStreetNEBNBTrafficMovements

One-wayStreetsTwo-PhaseOperation

兩相位控制12NMainStreetSideStreetEBNBWBSBTrafficMovementsFullIntersectionControlledMovements控制流向MainStreetSideStreetEBNBWBSBNConflictingMovements沖突流向MainStreetSideStreetEBNBWBSBN8-PhaseQuadLeftControl

(NEMA)8相位左轉控制MainStreetSideStreet15623874EBNBWBSBNPhase,RingandBarrier相位，帶域和隔斷15263784BarrierBarrierRing1Ring2MainStreetSideStreetCycleLength15623874NLTControlandPhasingSequence左轉控制和相位順序Left-turnTreatment/ControlPermitted許可(nophase)Protected保護

Protected/Permitted保護/許可Left-turnSequenceDualLTLeading(preferred)雙左轉前置DualLTLagging雙左轉后置

Split分方向控制

Lead/Lag一前一后

PhasingSequence相位順序

Left-turnLeading左轉前置15263784BarrierBarrierRing1Ring2152526151626PhasingSequence

Lead-Lag一前一后25163784BarrierBarrierRing1Ring2252616PhasingSequence

LaggingLeft-Turn左轉后置26153784BarrierBarrierRing1Ring2262515PhasingSequence

LeadingLTPhasingSequence

LaggingLTSignal

SystemClassification信號系統分類TraditionalSystems

傳統系統Closed-Loop(FieldMaster)閉路CentralizedComputerControl中央電腦控制Adaptive自調節系統

SignalTimingProcess信號配時過程Data

Collection收集數據SignalTimingDevelopment設計信號配時FieldImplementation實地應用BasicTerminology基本術語Cycle周期PhaseSplit相位時長PhasingSequence相位順序Offset時距Force-off強制關閉CycleLengthandSplitCycleLengthAllsignalsmusthaveacommoncyclelengthtoachievecoordination所有信號有共同周期Split分時Split=Green+Yellow+All-redSignalCoordination信號協調Intersection#1Intersection#2EastBoundOffset時距OffsetisthetimedifferencebetweentworeferencepointsOffsetmustbespecifiedbyPhaseBegin/endphaseOffset=0~cyclelength

Offsetф2,6ф2,5ф1,5ф4,8ф2,6ф1,5ф4,8ф3,7Localzero本地0時Localzero本地0時Whenthelocalzerooccursat40secofthemasterclockWesaytheOffset=40secTime-SpaceDiagram

One-wayStreet時距圖-單行路2684G=25Y=5R=30G=35Y=5R=20Time#1#2SBBand268484268426Time-SpaceDiagram

Two-wayStreet雙向路G=25Y=5R=30G=35Y=5R=20Time#1#2SBBandNBBand2684268484268426Bandwidth帶寬

(DualLTLeading)雙左轉前置26#1#215SB:20secNB:8sec26158426842684Bandwidth–Adjusted調整后的帶寬(DualLTLeading)#1#2SB:20secNB:12sec8426842626152615Bandwidth–Adjusted調整后

(Lead/Lag)84#1#2SB:20secNB:20sec2615261584268426Time-SpaceDiagramDemoCaseDemo–CA49,Auburn

BeforeAfter53CaseDemo–CA4954Auburn,CA-BeforeAuburn,CA-AfterAuburn,CA-CombinedDiamondInterchangeTightDiamond(<400ft)Compressed(400~800ft)Conventional(>800ft)SignalPhasesat

aDiamondInterchangeSignalPhasesat

aDiamondInterchangeBASIC3-PHASE2685A148BASIC3-PHASE2685A148BASIC3-PHASE2685A148BASIC3-PHASE26485A226BASIC3-PHASE26485A315BASIC3-PHASE26485A315BASIC3-PHASE26485A315VirginiaStreet/I-80Signals65FreewayInterchanges66AfterBeforeDDI67WhyDDIAbout20inoperation,50underconstructionAcost-effectivealternativefordiamond(noneedtowidenthebridge)Highercapacityduetoreducedcriticalphases(left-turnandU-turntrafficgoingtofreewaydonotstop)IssuesDrivingontheleftsidePedestriancrossingNothroughtrafficontheoff-ramp*CoordinationwithadjacentsignalsandrampmeteringStateofthePracticeNoanalyticalcapacityandLOSproceduresareavailableManydifferentphasingoptionsarepossiblebutnotyetwellrecognizedMostlyrelyonVISSIMfortheanalysis

DDIPhasingSchemesOff-rampcontroltypeaffectssignalphasing.Anyproposedschemeshouldbeeasytoimplementusingstandard8-phasecontrollers.Considerationofpedestriancrossingandtiming.Off-rampControlType71Off-rampControlOptionsBothsidesareyieldorstopcontrolOnesideisyield/stopandonesidesignalLet-turnissignalandrightturnisyield/stopSignalizedrightturnwith/withoutRTORPhasingScheme1(1a)

2-StageSplitwithOff-rampOverlapTwoNEMAphasesandtwocriticalphasesOff-ramptrafficlikelystops72?3?3?3VideoDemoPhasingScheme1(1a)

2-StageSplitwithOff-rampOverlapTwoNEMAphasesandtwocriticalphasesOff-ramptrafficlikelystops73?4?4?4VideoDemoPhasingScheme1Variation(1b)TwoNEMAphasesandtwocriticalphasesOff-ramptrafficlikelystops74?3?3?3VideoDemoPhasingScheme1Variation(1b)

75?4?4?4VideoDemoTwoNEMAphasesandtwocriticalphasesOff-ramptrafficlikelystopsPhasingScheme1Variation(1b)

76VideoDemoTwoNEMAphasesandtwocriticalphasesOff-ramptrafficlikelystopsScheme2

2-StageConcurrentwithOff-rampOverlapArterialphasesstarttogether,whichcanbeprogressedifthephaselengthisshorterthanthetraveltimeOff-ramptrafficdoesnotstop77?4?8?3?7?7?3VideoDemoScheme2

2-StageConcurrentwithOff-rampOverlapArterialphasesstarttogether,whichcanbeprogressedifthephaselengthisshorterthanthetraveltimeOff-ramptrafficdoesnotstop78?4?8?3?7?7?3VideoDemoScheme3(Reno)

3-StageSplitwithoutOff-rampOverlapEliminateinternalstopsLessefficientduetosplitphasing79?4?3AB?2?6VideoDemoScheme3(Reno)

3-StageSplitwithoutOff-rampOverlapEliminateinternalstopsLessefficientduetosplitphasing80?4?3AB?2?6VideoDemoScheme3(Reno)

3-StageSplitwithoutOff-rampOverlapEliminateinternalstopsLessef