九十一年度防灾国家型科技计画成果报告

GPN1009105460900801930731AbstractTyphoonsandrainstormsfrequentlyinvadeTaiwan;asaconsequence,debris-flowsoccurredoccasionallyinrecentyears.Especially,typhoonHerbof1986inducedagreatdebris-flowdisasterduetoitsunusualheavyrains.Moreover,after921Chi-ChiEarthquakethenumberofpotentialdebris-flowgulliesrushesupfrom485to1024.Intheyearof2001,undertheinvasionoftyphoonsTorajiandNarilarge-scaledebris-flowsoccurredinmanymountainousplacesinTaiwan,notonlydestroyinghousesbutalsodamagingroadsandbridges.Thetrafficinterruptionmaderescueeffortsverydifficult.Besides,thesocialandeconomiclossesbecameveryhugeduetotheimpairingoftransportationlifelines.Roadsandbridgesareusuallyline-shapeinfrastructures;theysometimespassthroughdebris-flowzones.Themainobjectiveofdebris-flowcountermeasuresfortransportationlinesistostayawayfromitand,ifnotapplicable,tokeepmenandvehiclespassthroughsafely.Regardingtothispointofview,thisprojectfirstfocusedonjudgmentofhighpotentialdebris-flowcreeks,evaluationofitsdegreeofhazard,debris-flowrheology,numericalsimulationonimpactforcestobridgestructures,anddamagepatternsofbridgessubjecttodebris-flows.Then,basedonthebefore-mentionedresearchresults,theprinciplefordesigningbridgesoverhighpotentialdebris-flowcreekswasformulatedalongwithcasestudies.Managementmeasuresfornew,existedanddamaged1bridgeswerealsopresented.Theoutcomewasexpectedtobeavaluablereferenceforbridgeengineerswhiledesigningormaintainingabridgepassingthroughdebris-flowcreeks.Itcouldalsoserveasabasicguidelineforthegovernmenttoestablishtherelateddesignspecificationstoincreasebridge’scapacityfordebris-flowhazard.Keywords:Debris-Flow,BridgeDesign,BridgeManagement.89k+95997k+40098k+40299k+117103k+l04112k+7892112k+877113k+278mmmm35.4kmkm2mm5621A27218216AASHOAASHTOAASHTOAASHTOAASHTO7LBL/BQm3secm8210K+436PCI3910MitigationPreparednessResponse11Recovery4.5.12Hungr,O.et.al.(1984),QuantitativeanalysisofdebristorrenthazardsfordesignofremedialmeasuresCanadianGeotechnicalJournal,Vol.21,pp.663~677.20022002Julien,P.Y.andLan,Y.,1991RheologyofHyperconcentrations,J.Hydr.Engrg.,ASCE,Vol.117,346-353.Liu,K.F.&K.W.Lai(2000)NumericalSimulationoftwo-dimensionaldebris-flowThe2ndinternationalconferenceondebrisflowhazardmitigationAug.16-18,pp.531-536.Takahashi,T.(1994)Japan-ChinaJointResearchonthePreventionfromDebrisFlowHazards,ResearchReportofGrant-in-AidforScientificResearch,TheJapaneseMinistryofEducation,ScienceandCulture,InternationalScientificResearchProgram,N0.03044085,March.Takahashi,T.,1980Debrisflowonprismaticopenchannel,J.Hydr.Div.,ASCE,Vol.106,No.3,pp.381-396.32.Bagnold,R.A.,1954Experimentsonagravity-freedispersionoflargesolidspheresinaNewtonianfluidundershear,Proc.oftheRoyalSoc.ofLondon,Vol.225,pp.49-63.AASHTO(1996),Standard13SpecificatiosforHighwayBridges,16thEdition1996.SABO(1987),MeasuresAgainstDebrisFlowonRoads,”ErosionControlDivision,SaboDepartment,PublicWorksResearchInstituteMinistryofConstruction,ISSN0386-5878,TechnicalMemorandumofPWRINo.2492.55.1415″1617181921µ2223×γ24××××××θαρ×θ××lnθsinHg××25ρρ××ρ××πρρ××ρ×ρ××ρ26≥≥2728