最新civilengineering土木工程概论英文课件CHAPTERSIXRAILWAYANDTRANSPORT资料.docx
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最新civilengineering土木工程概论英文课件CHAPTERSIXRAILWAYANDTRANSPORT资料.docx
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最新civilengineering土木工程概论英文课件CHAPTERSIXRAILWAYANDTRANSPORT资料
CHAPTERSIXRAILWAYANDTRANSPORT
6.1EvolutionoftheRailway
6.1.1HistoricalOutlineasketchysummaryofthemainpointsofanargumentortheory
Sincethedawnofhumanactivity,thequickandsafetransportationofpeopleandgoodshasbeenaconstantgoalofeveryorganizedsociety.Itisgenerallyacknowledged,thatthefoundationinnovationsinthedevelopmentoftransportationincludedthediscoveryofthewheel,therailwayandtheairplane.Railwaytrainsintheirpresentformfirstmadetheirappearanceatthebeginningofthe19thcenturyinBritishmines.Theirmaincharacteristicistheguidedmovementofwheelsbythetrackthroughmetal-to-metalcontact.
However,theforerunnersoftherailwayappearedmuchearlierthanthe19thcentury.Movementofcarriages四轮马车orwagons用运货马车运输货物onmetalguidesisillustratedina1550gravure(影印版aprintingplateusedintheprocessofgravure)foundinBasel(巴塞尔acityinnorthwesternSwitzerland),Switzerland,whichshowstransportationmethodsemployedintheminesofAlsace(aregionofnortheasternFrancefamousforitswines),TheguidedmovementofcarriagesingeneralwasalreadyknowninRomantimes,aswitnessedbygrooves细槽,凹槽carved雕刻inthestonepavementtofacilitateandspeedupthemovementofcarriages.
∙RailwayandOtherCompetingTransportationMeansTimeshaschanged,however,whatwasimpressiveintheearly20thcentury,wasthereducedsatisfactionwithrailways.Airplanesandprivatecars私家车;私人小汽车havebeenofferingtransportationalternativesateveryscale,whichhasgiventhepressureofcompetition,therailwayhadtomodernizeandimprove,especiallyasregardsspeed,reductionoftransportationcostsandbetterorganizationandimprovementoftheservicesoffered.Hence,wecometotheeraofhigh-speedtrains(Fig.6.I,Fig.6.2)operatingat250~~300km/h(aspeedof515km/hwasattainedbyFrenchRailwayin1990intestruns),combinedtransport(combinedrail-roadtransportation)andhigh-volumetransportforbothpassengers(commuterservice)andfreight(bulkloads).
Fig.6.1TheJapaneseShinkansenhigh-speedFig.6.2TheFrenchTGVhigh-speedtrain
∙Nevertheless,inparallelwiththeconventionalrailways(whicharebasedonmetal-to-metalcontact),experimentaldevelopmentproceededsincethemid-1970swithtechniqueswhich,althoughusingguidedvehicletravel(likerailways),avoidanycontactbetweenthemovingvehicleandbearingsub-structure.Thesearetheareotrain(Fig.6.3)andthemagneticlevitation磁悬浮train,ormaglev(Fig.6.4),which,intestruns试运转,hasattainedspeedsof422km/hfortheareotrainin1969and600kmhforthemaglevin1991。
magneticlevitationhigh-speedrailtechnology;trainissuspendedonamagneticcushionaboveamagnetizedtrackandsotravelsfreeoffriction
6.2.1TheApplicationofHigh-speedinRailways
High-speedtrains(withV>200km/h)representrailwaymakingresponsetothetransportmarketrequirementforreducedtraveltimes行程时间aperiodoftimespenttraveling.Highspeedswerepioneeredbytworailwaynetworks:
TheJapanesenetwork,withthe1964commissioning试车;试运转theactofgrantingauthoritytoundertakecertainfunctionsofthe"Shinkansen"high-speedraillinkbetweenTokyoandOsaka,withatopspeedof210km/h.
1.TheFrenchRailway,byinaugurationin1981the"TGV"巴黎至里昂间高速火车(TrainaGrandeVitesse)high-speedtrainbetweenParisandLyons,withatopspeedof260km/h,increasingto270km/hin1983andto300km/hin1989.
Bothlineswerebuiltonheavilytraveledroutes旅运路线showingsignsofsaturation饱和.Facedwithimprovingexistinginfrastructures下部构造;基本建设orbuildinganewhigh-speedline,thelatterwaschosen.High-speedlineswereconstructedinthe1980sinWestGermany(Hannover-WurzburgandMannheim-Stuttgart),inItaly(Rome-Florence),inSpain(Madrid-Sevilla),inFrance("TVGAtlantique"lineParis-Bordeaux)andrecentlyParis-Londonline(throughChannelTunnel).
Twoapproachestohighspeedscanbedistinguished.
∙Inthefirst,onlypassenger(客运列车atrainthatcarriespassengers)trainsrunonhigh-speedlines,withlowloadsperaxle,verysmalltoleranceontrackdefectsandlargegradients(渐变,梯度(upto35%).Thisapproachwasimplemented执行intheParis-Lyonslineandpresupposed预设的thehighpassengertraintrafficcouldmaketheconstructionandoperationofthenewlinecost-efficient(有成本效益的;合算的adj.有成本效益的;合算的
economical,paying
productiverelativetothecost)
Inthesecond,thenewhigh-speedlinesarerunbybothpassengerandfreighttrains,thecoexistence(existingpeacefullytogether)ofwhichentailshighermaintenancecostsandretireslowervaluesoflongitudinalgradient纵向坡度.Mosthigh-speedlinesarecurrentlydesignedformixedtraffic(bothpassengerandfreighttrains).
6.2.2ImpactofHighSpeedsontheReductionofRailTravelTimes:
Thereductionoftraveltimewasaconstantgoaloftherailways,ascanbeseenfrom|Table6.1.Onlywithhigh-speedtrains,however,weretherailwayabletoachieve400—700kmroutes,bywhichthetraveltimesequaltoorbetterthanairtravel
TraintraveltimereductiononcertainroutesTable6.1
Indeed,high-speedrailwayshavetheadvantagetoreachcitycentresandthusmaketraveltimesfromthecentreofacitytothecentreofanotherfarshorterthaforautomobilesandeven*inmanycases,shorterthanforairplanes(Table6.2)
Comparisonoftraveltimesfromthecentreofacitytothecentreofanotherfor
high-speedtrains,airplanesandautomobilesCeaseoftheParis-Lyonsroute)Table6.2
TGVtraveltimeaccess
Automobile*2)~
TGVtraveltime
AirplaneC1)
(onhighwayatatopspeedof120km/to
timetorailwaystation
1h50min
2h30min
2h30min—3h
5h
2.Thetimeindicatedisthesumoftheflighttime飞行时间;飞越时间,traveltimefromthecitycentretotheairportandcheckin报到,记录time.
3.Thetimeindicatedisthetimefromthecentreofacitytothecentreofanother,i.e.ittakesintoaccountthetimenecessary(about30min)foracartoreachthehighwayfromthecitycentre.
6.3AerotrainandMaglev悬浮列车;高速铁道磁力悬浮火车
6.3.1TheAerotrain
Thetechnologiesofareotrainandmagneticlevitation磁悬浮trainarebasedonguidedvehicletransport(likeconventionaltrains),butavoidanycontactofthemovingvehiclewiththebearingstructureonwhichtransportistakingplace,whereasrailwaysrelyonthemetal(wheel)tometal(track)contact.
Theareotrain(Fig.6.3)isavehiclerunningonaconcretebearingsubstructureinwithshapeofaninvertedbeinginsuchapositionthattopandbottomarereversed"T(Fig.6.5).
Propulsion推进;推进力isachievedwithoutanywheelsystem,byacompressedaircushionblownbetweenthevehicleandthebearingsubstructure.Theareotrainthusreplacestheadhesionforces,necessarytoconventionaltrains,bycompressedairlayer.
Thetechnologywasdevelopedinthe1960sinFranceandin1969hadachievedtheimpressivespeedof422km/h.
Eventhoughtherewerevariousplansforareotrainconstruction(e.g.Paris-Orleanswhere18kmofbearingsubstructurehadevenbuilt,Brussels-Luxembourg,etc.),abandonedinthe1970sforvariousreasons.Themainonesare:
(1)Thenewtechniqueisnotcompatiblewithconventionalrailways.
Fig.6.5Theareotrainprinciple
(2)constructionprovedthatitwasmuchmoreexpensivethananewconventionalline(withoutconsideringthecostbeingoffsetbythemuchlowermaintenancecostoftheareotraincomparedwithconventionalrailways),
Energyconsumption(duetotheairturbineusedforareotrainpropulsion)ismuchhigherthanforconventionaltrains,
Thecarryingcapacityofanareotrainwaslow(64~96passengersintheprototype,butupto160passengerintwo-cartrainsplannedforlatter).
Secondaryreasonsarepassengersafetyconsiderations(possiblefireinthevehiclewhichrides5maboveground),noiseandquestionableoverallaesthetics.
6.3.2MagneticLevitation三里岛核电站Trains(Maglevs)
Inmagneticlevitation磁悬浮trains(Fig.6.4),contactbetweenthebearingsubstructureandthevehicleisavoidedandthepropulsion(apropellingforce)isensuredbymagneticphenomena.
Thebearingsubstructureisaconcreteslab混凝土板intheshapeofaninverted"T"(orofa"U").Suitablylocatedmagnetsandcoils线圈generatetheforcesrequiredforlevitation(movementupwardinvirtueoflightness),propulsionandguidance.However,recentresearchhasshownthattheconstructionofasupercon工程技术ducting.管道,导管magnetfulfillingtheabovethreerequirementsispossible.Thistechnologywasdevelopedinthe1970sinGermanyandJapan,wherein1979duringthecourseoftestingaspeedof517km/hhasbeenattained.InGermany(Emsland),amagnetic-levitation升空;飘浮testtrackwasbuiltwiththefollowingcharacteristics:
Bearingsubstructureofcompositeconstructionandsuperelevatedsectionataheightof5m
Designspeed400km/h
Cars54mlong,weighing120tons,withacarryingcapacityof200passengers
Minimumhorizontalradiusofcurvature曲率半径4,000mandmaximumlongitudinalgradient10%.
Amagnetic-levitationtesttrackof42.8kmlongwasconstructedinJapanin1990.However,expresslinksofairportswithurban,areasmaybeinthefuturecandidatesforthemaglevtechnology.
6.3.3UrbanRailServices
Inanagewithexplodingtrafficproblems,therailwayscandecisively果断地;决然地contributetotheiralleviationbytheirlargecarryingcapacities(Table6.3,).Manyrailwaylinesconnectingcitycentrestothesuburbsarebeingmodernizedandusedforurbanrailservices,thusrelievingthetrafficproblemofthecities.
Carryingcapacity承载能力ofvarioustransportsystemTable6.3
6.4TheTrackSystem
∙6.4.1AreasofRailwayEngineering:
"Track,轨道;足迹,踪迹;小道Tract
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