简介：一条即时分析途径被开发在完全扭曲加速的摆动的流动预言表流动运输。途径在一张活动海床上面从速度和集中侧面的指数的近似被导出，并且它特别地考虑阶段铅的因素；阶段落后(即阶段剩余和阶段移动)；加速修正；并且不对称现象在砍应力，粗糙高度，和边界层开发。途径能在一张活动海床上面预言网边界层流动，并且能回复到古典水流带来的碎石模型。即时并且网沉积运输率用途径被学习。在一个向陆的流动阶段的即时沉积运输率能被代表在被证实在阶段剩余与减少在1和5之间变化的速度的力量功能接近。用途径预言的网络沉积运输率用测量数据的可观的数量被验证，并且与存在相比即时并且考虑阶段的一半时期类型模型落后或加速修正。为在完全扭曲加速的摆动的流动的网沉积运输率，阶段剩余不比向陆、近海的加速阶段之间的扭曲加速的边界层差别重要。

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简介：存在抵抗公式为石子床溪流生产大量磨擦因素估计。这份报纸的目的是以Darcy-Weisbach磨擦因素f开发一个可靠抵抗公式。出版数据被屏蔽并且过去常建立公式。存在公式认为f仅仅是相对粗糙D84/R的功能，在R是水力的半径，D84是指的粒子尺寸的地方等于或超过84%床沉积的中间的直径。在这份报纸，f除了相对粗糙被看作弗鲁德数字的功能。为D84/R的f>1为D84/R比那显示一个不同趋势<1也许由于为D84/R的对数的速度分布的无效假设>1。为D84/R的一个f公式<1被建立了。

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简介：TheChi-Chiearthquakein1999causeddisastrouslandslides,whichtriggerednumerousdebrisflowsandkilledhundredsofpeople.Acriticalrainfallintensitylineforeachdebris-flowstreamisstudiedtopreventsuchadisaster.However,settingrainfalllinesfromincompletedataisdifficult,sothisstudyconsideredeightcriticalfactorstogroupstreams,suchthatstreamswithinaclusterhavesimilarrainfalllines.Ageneticalgorithmisappliedtogroup377debris-flowstreamsselectedfromthecenterofanareaaffectedbytheChi-Chiearthquake.Thesestreamsaregroupedintosevenclusterswithdifferentcharacteristics.Theresultsrevealthattheproposedmethodeffectivelygroupsdebris-flowstreams.

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简介：Intherillerosionprocess,run-onwaterandsedimentfromupslopeareas,andrillflowhydraulicparametershavesignificanteffectsonsedimentdetachmentandtransport.However,thereisalackofdatatoquantifytheeffectsofrun-onwaterandsedimentandrillflowhydraulicparametersonrillerosionprocessatsteephillslopes,especiallyintheLoessPlateauofChina.Adual-boxsystem,consistingofa2-m-longfeederboxanda5-m-longtestboxwith26.8%slopegradientwasusedtoquantifytheeffectsofupsloperunoffandsediment,andofrillflowhydraulicparametersontherillerosionprocess.Theresultsshowedthatdetachment-transportwasdominatedinrillerosionprocesses;upsloperunoffalwayscausedthenetrilldetachmentatthedownsloperillflowchannel,andthenetrilldetachmentcausedbyupsloperunoffincreasedwithadecreaseofrunoffsedimentconcentrationfromthefeederboxoranincreaseofrainfallintensity.Upsloperunoffdischargingintotherillflowchanneloranincreaseofrainfallintensitycausedtherillflowtoshiftfromastratumflowintoaturbulentflow.Upsloperunoffhadanimportanteffectonrillflowhydraulicparameters,suchasrillflowvelocity,hydraulicradius,Reynoldsnumber,FroudenumberandtheDarcy-Weisbachresistancecoefficient.Thenetrilldetachmentcausedbyupsloperunoffincreasedastherelativeincrementsofrillflowvelocity,ReynoldsnumberandFroudenumbercausedbyupsloperunoffincreased.Incontrast,thenetrilldetachmentdecreasedwithanincreaseoftherelativedecrementoftheDarcy-Weisbachresistancecoefficientcausedbyupsloperunoff.Thesefindingswillhelptoimprovetheunderstandingoftheeffectsofrun-onwaterandsedimentontheerosionprocessandtofindcontrolstrategiestominimizetheimpactofrun-onwater.

简介：Thispaperreportsaflumeexperimentofflowandsedimentmovementinacavity.Theflowvelocity,sedimentconcentrationandthemechanismofhydraulicsortinginthecirculationflowarediscussed.Thequantityandpatternsofsedimentdepositioninthecirculationareaarestudiedaswell.

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简介：Theresultsofmathematicalmodellingofunsteadyflowconditionscoupledwithspecificsedimenttransportrelationsarepresentedhere.SimultaneoussolutionsofthedeSaintVenantequationswiththreedifferenttransportrelations,namelytheEngelund-Hansenequation,Grafequation,andanempiricalequationarepresented.TheresultsobtainedwerecomparedwiththosefromtheFluvial-12programunderthesameinputconditionsandreasonablecorrelationwasobserved.Theadvantagesofthecoupledmethodforsimultaneoussolutionoftheequationscompriseahigherdegreeofaccuracy,thepossibilityofintroductionofanydesiredtransportequationintothemodelandthepossibilityofintroducinganyboundaryconditionsintothemodelalongsideacompleteunsteadyflowmodelling.

简介：Localscourmayoccurwhenahydraulicstructureispositionedinachannelwithanerodiblebed.Herewithinvestigatedexperimentallyaretheerosionandflowpatternduetoawaterjetpassingoverachannelbedattheasymptotic(final)state.Thedevelopmentofthescourhole,itsmaximumscourdepthandlength,arerecordedandcomparedwithavailablescour-depthrelations.Twosetsofexperiments(seeTable1)werecarriedout.Set1(3runs)wasconcernedwithmeasuringtheverticalinstantaneousvelocitydistributioninthescourhole.Thescourholeattheasymptotic(final)state,t≈100[h]wasinvestigated.Set2(5runs)wasconcernedwithstudyingthephysicsofscouring.Thescourholeataboutmid-state,t≈0.5[h],wasinvestigated;subsequentlythescour-holedepthwaslinearlyextendedonthesemi-logscaleto72[h];novelocitymeasurementswereperformed.Thepresentdataareputincontextwithsome(popular)existingrelations;recommendedisamodificationofsomeoftheserelations.

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简介：刺激堤是在河训练的一个重要元素那在流动地，沉积运输和床地形学里创造快速的变化。在隧道拐弯的流动和沉积运输的机制是很复杂的，特别当一个刺激堤在拐弯被构造时。大多数流动行为上的以前的调查并且在刺激堤附近搜索在直隧道被执行。在流动的实验的结果在90度隧道在一个刺激堤附近回答并且搜索的这份报纸弯曲被介绍。有一致谷物尺寸的沙被用作床材料。实验与分泌物的不同价值在拐弯为不同地点和刺激堤的不同长度被进行。在一个刺激堤附近的三块维的流动地被调查。最大的深度搜索在拐弯被相关到弗鲁德数字，长度和刺激堤的地点。

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简介：Travelingandstationaryinternalhydraulicjumpsindensitycurrentswithpositiveornegativeentrainmentcoefficientswereanalyzedbasedonsimpleassumptions.Anexpressionofinternalhydraulicjumpswithentrainmentcoefficientswasderived.Experimentaldata,publishedinliterature,ofstationaryinternalhydraulicjumpsinturbid,thermalandsalinedensitycurrentsincludingmeasuredvaluesofwaterentrainmentwereusedtocomparewiththeory.Comparisonwasalsomadeoftravelinginternalhydraulicjumpsbetweenmeasureddataandtheory.

简介：Theformationoflandslidedamsisofteninducedbyearthquakesinmountainousareas.Thefailureofalandslidedamtypicallyresultsincatastrophicflashfloodsordebrisflowsdownstream.Significantattentionhasbeengiventotheprocessesandmechanismsinvolvedinthefailureofindividuallandslidedams.However,theprocessesleadingtodominofailuresofmultiplelandslidedamsremainunclear.Inthisstudy,experimentaltestswerecarriedouttoinvestigatethedominofailureoflandslidedamsandtheconsequentenlargementofdownstreamdebrisflows.Differentblockageconditionswereconsidered,includingcompleteblockage,partialblockageanderodiblebed(noblockage).Themeanvelocityoftheflowfrontwasestimatedbyvideos.Totalstresstransducers(TSTs)andLaserrangefinders(LRFs)wereemployedtomeasurethetotalstressandthedepthoftheflowfront,respectively.Underacompleteblockagepattern,aportionofthedebrisflowwastrappedinfrontofeachretainedlandslidedambeforethelattercollapsedcompletely.Thiswasaccompaniedbyadramaticdecreaseinthemeanvelocityoftheflowfront.Conversely,underbothpartialblockageanderodiblebedconditions,themeanvelocityoftheflowfrontincreasedgraduallydownwardalongtheslopingchannel.Dominofailuresofthelandslidedamsweretriggeredwhenaseriesofdams(completeblockageandpartialblockage)weredistributedalongtheflume.However,notallofthesedominofailuresledtoenlargeddebrisflows.Themodesofdamfailureshavesignificantimpactsontheenlargementofdebrisflows.Therefore,furtherresearchisnecessarytounderstandthemechanismsofdominofailuresoflandslidedamsandtheireffectsontheenlargementofdebrisflows.

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简介：Thefrontpartoftheflowisveryimportantandcomplexinthecaseofdebrisflowwherethereisanaccumulationoflargeboulders.Itisimportanttocontrolordampentheenergyofthefrontalpartofadebrisflowforthesafetyofthedownstreamareabecausetheimpactpressureofdebrisflowismuchgreaterthanthatofclearfluid.Themainobjectiveofthisstudyistoanalyzethehydrauliccharacteristicsoftheproposeddam(i.e.closed-typedamwithflap).Theverticalpressuredistributionofthistypeiscomparedwithconventionaldamtypes.Intheexperiments,thetotalpressureassociatedwithmajordebrisflowswasrecordedinrealtimebyasystemconsistingoffourdynamicpressuresensorsinstalledondifferenttypesofdam.Theresultsfromexperimentaldataclearlyshowthatthedamwiththeflaphasadvantagesofcapturingthedebrisflowwithlargebouldersandcontrolsthetotalpressurebyflowcirculationduetopresenceoftheflapstructurecomparedtoaclosed-typedamwithoutflap.Furthermore,theempiricalcoefficientsofhydrodynamicandsolidcollisionmodelswereproposedandcomparedwithavailablecoefficients.