道路交通詞匯2 street and transportation glossary 2

1、[b]Density——[b]thenumberofvehiclesoccupyingaroadlaneperunitlengthatagiveninstant.[b]Flow——[b]thenumberofvehiclespassingapointperunitoftimeoftencalledvolumewhenthetimeunitisonehour.[b]Gap——[b]thetimeintervalbetweenthepass

2、ageofconsecutivevehiclesmovinginthesamestreammeasuredbetweentherearoftheleadvehiclethefrontofthefollowingvehicle.[b]Headway——[b]thetimeintervalbetweenpassageofconsecutivevehiclesmovinginthesamestreammeasuredbetweencrespo

3、ndingpoints(e.g.frontbumper)onsuccessivevehicles.[b]InterruptedFlow——[b]occurswhenflowisperiodicallyinterruptedbyexternalfixturesprimarilytrafficcontroldevices.[b]JamDensity——[b]thedensitywhenspeedflowarezero.[b]PHF(Peak

4、HourFact)——[b]Thisdescribestherelationshipbetweenhourlyvolumethemaximumrateofflowwithinthehour:PHF=hourlyvolumemaximumrateofflow.Fthe15minuteperiodsPHF=volume4x(maximum15minutevolumewithinthehour)[b]Shockwaves——[b]Shockw

5、avesoccurasaresultofdifferencesinflowdensitywhichoccurwhenthereareconstrictionsintrafficflow.Theseconstrictionsarecalledbottlenecks.Thespeedofgrowthoftheensuingqueueistheshockwaveisthedifferenceinflowdividedbythedifferen

6、ceindensity.[b]SpaceMeanSpeed——[b]thearithmeticmeanofthespeedofthosevehiclesoccupyingagivenlengthofroadatagiveninstant.[b]Spacing——[b]thedistancebetweenvehiclesmovinginthesamelanemeasuredbetweencrespondingpoints(fronttof

7、ront)ofconsecutivevehicles.[b]Speed——[b]thetimerateofchangeofdistance.[b]TimeMeanSpeed——[b]thearithmeticmeanofthespeedofvehiclespassingapointduringagiventimeinterval.[b]TravelTime——[b]thetotaltimerequiredfavehicletotrave

8、lfromonepointtoanotheroveraspecifiedrouteunderprevailingconditions.[b]UninterruptedFlow——[b]occurswhenvehiclestraversingalengthofroadwayarenotrequiredtostopbyanycauseexternaltothetrafficstreamsuchastrafficcontrolBottlene

9、ck瓶頸BottomCourse底層BottomFlange下翼綠Boulder卵石Boxcaisson沉箱；箱式沉箱；匣式沉箱BoxCulvert箱涵；箱形涵洞BoxDrain水溝渠；匣形溝渠Boxgirder箱形梁Bracing支撐BracketChassis拖架BrakefailureDefectivebrake煞車失靈Brakelight煞車燈BrakeReactiontime煞車反應(yīng)時(shí)間；制動(dòng)反應(yīng)時(shí)間BrakingDistan

10、ce剎車視距（停車視距）Brakingsystem煞車系統(tǒng)BranchBoundAlgithm分枝界定法Breakdowns故障BreakingofEmulsion乳化瀝青黏結(jié)BreakingWave碎波Breakaway脫離式接頭Breathalcoholconcentration呼氣酒精含量BrickPavement磚鋪路面；磚鋪面BrickPavementRoad磚鋪路BrickRoad磚面路Bridge橋梁BridgeAbutm

11、ent橋臺(tái)BridgeApproach橋粱引道Bridgebearing橋支承Bridgedeck橋面板Bridgedeckflo橋面Bridgeexpansionjoint橋面伸縮縫Bridgeflo橋面Bridgehead橋塔Bridgeinspection橋梁檢測(cè)BridgeManagementSystem橋梁管理系統(tǒng)Bridgepier橋墩Bridgerailing橋欄桿Bridgespan橋跨Brightness照杜；輝杜；明