河道橋墩處水力特性及其對河冰過程影響研究.pdf

1、分類號P338.4UDC556學校代碼10129學號2013206051河道橋墩處水力特性及其對河冰過程影響研究RiverCoursePiersHydraulicacteristicitsInfluenceonRiverIceProcessesResearch申請人：夏天學位類別：工程碩士領域：水利工程指導教師：李暢游教授論文提交日期：二○一五年六月RiverCoursePiersHydraulicacteristicitsInflue

2、nceonRiverIceProcessesResearchAbstractTheriverlocatedatthehighlatitudewillbefrozeninwinterthawedcarelesslyinspring.Duringtheprocessoffrozenthawedicejamicedammaybehappenedwhichwillbecausediceflooddisaster.Differentchannel

3、fmshavethedifferentimpactsontheprocessofthefmationoftheriverice.ThisarticlethroughmeasuredthesurfacevelocityoftheYellowRiver(InnerMongolia)downstreamcountyHaishengBuLangoftheYellowRiverbridgeusingthesoftwaretosimulatesof

4、twarefsurfacevelocityatthesametime.Thenconcludedthatthenaturalriverbridgepierinthehydraulicacteristicsusethistoanalyzetheprocessoffrozenthawedcomparewiththefieldobservationexperiment.Theresultshowthattheexistenceofthepie

5、rhavetwomainwaytoinfluencetheprocessofthefrozen.FthecasethatthepierwhichlocatedinthedleoftheriverbecauseofthelengthofthepierisshterthantheriverchannelNearthebridgepiervelocityislargesoithasnotimpacttheicetransptingabilit

6、yoftheriverchannelitwillnotimpacttheicetransptingintheearlydleoftheiceflow.Inthelaterperiodoftheiceflowbecauseofthedensityoftheiceflowhaveincreaseditmaybeblockedinthisplace.Fthecasethatthepierwhichlocatedneartheriverbank

7、itwilldecreasethevelocitynearthebridgeInadditionbecauseoftheblockingeffectofpierstheiceflowiseasiertoaccumulatedinthisplacesothealluviallicewillbefmed.Withtheincreasingnumberofthelicetheicetransptingabilityoftheriverchan

8、nelwillbedescended.Whenthedensityoftheiceflowcontinuestoincreasetheicewillbeblockedinthisplacetheiceflowwillbeaccumulatedinthisplacethanicesheetwillbefmedextendstotheupstreambefrozen.Theperiodofthawdividedintotranquilbre

9、akviolentbreak.Tranquilbreakdominatedbythermodynamicfactstheexistenceofthepierswillnotaffectthetranquilbreakcarelessly.Violentbreakisusuallyaccompaniedbyalargenumberofhugechunksoficetotranspttothedownstream.Whenthenumber